The Complete History of the Earth: Everything Before the Dinosaurs SUPER CUT

foreign [Music] so at the start of this week I was at a bit of a loss of what to make a video about I have a lot of projects that I have in the works currently but when I sat down to write something I was just drawing a blank so I did what I and many other content creators do when they're facing the dreaded blank piece of paper I went to the comment section of some of my previous videos to look for ideas and I started to notice that there was a lot of people requesting a similar type of video specifically just in general a broad idea of just different periods in Earth's history I get a lot of comments just saying talk about the pleistocene or talk about the Triassic which I've already done quite a bit now or talk about the devonian okay and all this kind of got me thinking what if I do all of it what if I made a series of videos where I basically broadly cover the lore of the Earth from the beginning all the way to the modern times so that's what this video is going to be the start of and I know that starting at the very beginning this video might not exactly rank in the search since it's probably gonna feel more like an astronomy or geology video than a paleontology video but eventually I'll be able to say that I've given a timeline to Earth's history that I can reference in future videos and for this one I want to start with a little bit of context and then I'll be starting at the beginning then going from there and this doesn't mean that this is what I'm going to be doing every single week just something that I'll be adding a video to every so often basically just whenever I either want to or any time that I can't think of anything else to talk about I'll plug one of these in but with all that out of the way let's get started with a little bit bit of context a little something to lay out the chapters of this story so before we really get into this I think I should probably explain a few things for those who don't already know how geologic time is measured the history of the earth spans roughly 4 billion 540 million years this is an absolutely unfathomable amount of time so to be able to help wrap our heads around something so vast we've organized the history of the earth into several different chronological units or Geo chronological units if you will the smallest unit of measurement that we'll be using is ages although there isn't a hard and fast rule to this ages are generally measured in up to millions of years epochs are normally measured in several million years periods are normally measured in tens of millions of years eras are normally 50 to several hundred million years and finally eons normally cover half a billion years or more now as we move forward through time you'll start to notice that I start covering smaller and smaller sections of the timeline this is because the farther back in time you go the less complete our geological record is for example the Cretaceous Period lasted from 145 to 66 million years ago so roughly 79 million years this is a longer span of time than the entire cenozoic ERA this is because the cenozoic is chopped up into smaller measurements since we have so much more data to identify if a span of time is different enough to Warrant a division well that and the fact that the cenozoic is not actually over yet but this is just something to keep in mind while I tell you all the story of where everything on Earth came from and to start that story off I'm going to have to go all the way back The Story begins with a giant molecular cloud swirling around the Milky Way galaxy around 4.6 billion years ago yeah I did say I was going all the way back didn't I wait oh god I've gone so far back in time that I'm an atheidium bromide molecule I'm literally a building block of life no as the clouds spun gravity started to make the heaviest materials Gather in the center while the rest started to form what's called a protoplanetary disk and as you might have guessed eventually the mass of ultra heavy material became our sun and the dust and particles that made up the discs started to form the newborn planets and other celestial bodies and during this time our planet was born originally just another unassuming world floating around a new star and currently Earth is about as far away from being recognizable as it ever will be in fact it probably looked more like Mustafar from Star Wars so hellish was our future home that this entire Eon was given the name the hadian and yeah it's actually named after the Greek god of the underworld James Woods it was literally hell on Earth in the most literal sense for the majority of the first 600 million years and to make things even worse because there was so much other stuff out in the rest of the solar system forming there was a lot more objects crossing paths in the form of impacts and sometime within the first hundred million years the earth is believed to have had an impact that would change the course of its future around this time the Earth was starting to cool however it was still a hellacious ball of rock with very little chance of life ever forming the average global temperature was around 230 degrees Celsius or 446 degrees Fahrenheit however many of the denser materials were starting to solidify there was one element that was only able to condense to liquid form because its temperature to form solid was down at 32 degrees Fahrenheit A compound of hydrogen and oxygen that would become the single most abundant ingredient in the recipe of Life water and the only reason why it was even able to form a liquid is because the atmosphere was 27 times as dense as it is today how did that atmosphere even get there and what's more how do we even have the tithes there was no way for the tides to form because there was no object close by to create a gravitational pull needed for it that is until a stray Planet straight up T-boned us yeah I know it sounds like some Star Trek grade stuff right now but the most plausible Theory to the moon's Origins is that it was formed from an impact between the Earth and a planet that we now call Thea it's believed that part of Thea remained in our orbit as some of it was ripped away and added to the big ball of clay that we call home and the vaporized particles from this impact enveloped the globe it was a combination of this with the helium and oxygen that had been slowly leaking away from the planet for the first hundred million years that we believe comprised our planet's earliest atmosphere not one that we could currently breathe mind you but this was a seed where everything really got started so there we have it just like that the stage is set even though the Earth is still highly unstable geologically there's a moon in the night sky an atmosphere of mostly CO2 sulfur and helium and a tiny bit of liquid water in the lowest parts of our Rocky world it's starting to really feel like home but by the end of the hadian things were really starting to cool off a lot more and this seems like a pretty good place to leave the story off because honestly there's still a ton we don't know about this time there's only a very small handful of locations where rocks that are this old even exists because right where we're standing right now at the end of the hadian there's still four billion years that we still have to travel to get back to our time and rocks just don't last that long on a geologically active world so I hope you enjoyed this first chapter in the history of our planet if you did give this video a like I'm really looking forward to continuing the story as well as continuing to make other videos about all different stuff maybe in the next video I might actually get to cover something that's you know alive now if you excuse me I'm going to sit next to this hydrothermal vent and try to figure out how to turn back to normal take care everybody foreign [Music] [Music] so in our last video we started our journey exploring the complete history of life on Earth we talked about how our world was born as well as what it was like for the first 600 million years of its development in short it wasn't pretty lava a toxic atmosphere and constant bombardment from other objects in the inner solar system were just part of daily life on Earth during that time but things were starting to slowly improve on this little red marble as we enter the archaean Eon and this is a stretch of time that's three times longer than the stretch of time that we covered in the last one by the time we get to the end of this video we'll be about halfway through the complete history of the earth and luckily we have a little bit more information to go on than we did last time but as I said before this will probably be the case with every video going forward because the closer we get to the present day the more complete our geological record is and for the first time we now have enough data to actually divide this Eon into eras however we still don't know enough about this time to Merit giving each era its own individual video but we'll get to that point soon enough so now let's get into it because we still have a long way to travel and before things get better it looks like things are going to have to get a lot worse the eor Keon began around 4 billion years ago as the Earth was in the throes of a major crisis now we've already talked about how our planet has had to deal with constant barrages of impacts from other objects in our solar system including the major impact that would lead to the formation of the moon but sometime before the end of the Haitian there would be a drastic increase in the frequency of impacts from asteroids and comets so much so that from 4.1 to 3.8 billion years ago we enter a time that has come to be referred to as the late heavy bombardment some estimates calculate that there may have been as many as a few substantial impacts every Millennium or so this might sound like a bad thing and it probably would be had we actually been there to witness this event taking place but in all actuality it may have had long-term effects that led to our world becoming one step closer to the Earth we know today you see comets are not just solid chunks of rock like asteroids they're actually made up of mostly dust and ice and as you may know ice is frozen water and although there was water on Earth already not nearly as much as a 70 percent that we have covering the planet today it's believed that a large percentage of the water we have arrived in the form of cosmic snowballs being hooked at us every few centuries now this is one of the main things that scientists have come to Define this era by and even though this event would start to slow down by 3.8 billion years ago as the moon got further and further away from the earth recent evidence has led many to believe that there may have been at least one impact around the size of the one that wiped out the dinosaurs on average every 15 million years throughout the entire archaean starting at 3.6 billion years ago we come to the Paleo archaean an arrow lasting around 400 million years this time has been defined by two major events that we know of so far the first one being as the sea level Rose and the crust of the earth began to cool the first large land mass would form now we can't know exactly what this land mass actually looked like but we know that it was at least partly made up of Western Australia and South Africa it was given the name valbera and on its coasts would be the most important step in the history of our planet yet we have at last arrived at the earliest evidence of life now there's a very good chance that single-celled life had at least existed for millions of years before this but this is the earliest evidence that has been found in the fossil record and it might not seem like much but it's believed that these little microbes called cyanobacteria would make a massive change to the entire world simply by doing what they do for those of you who play Spore we've officially now entered the cell phase these little guys lived in colonies and were constantly expanding along the coasts and eventually into the riverways of valbera they created their own nutrients using photosynthesis a process that works so well that has been passed down to all living plants today thriving in the carbon dioxide Rich atmosphere these first organisms would arguably become Earth's very first rulers you know I suddenly feel proud to be a cyanobacteria don't judge me as we get into the mezzoor key in around 3.2 billion years ago we start to see a new phenomenon take place as a result of the cooler surface temperature of the ground with the still active volcanism underneath plate tectonics begin to move the crust around the globe causing continents to tear apart and form together to form supercontinence by this point the global temperature had already dropped considerably from what it was back in the hadian but it still isn't what we would call comfortable by today's standards around 50 degrees Celsius or 122 degrees Fahrenheit and 85 degrees Celsius or 185 degrees Fahrenheit was the average at this time this is probably the case because the atmosphere was still mostly comprised of greenhouse gases like methane and the previously mentioned carbon dioxide that was fueling the cyanobacteria Empire but this was something that would actually start to change as the current rulers of the archaean earth spread and diversified into different species and started to form complex microbial ecosystems as the cyanobacteria took over they would start to do something that we normally think of as only something that humans are capable of drastic changes to the global climate and they basically did this simply by existing you see as these microorganisms took in CO2 they would produce oxygen as a byproduct this would lead to a drop in temperatures until eventually by 2.9 billion years ago the earth would experience its very first glaciation at the poles so in about half a billion years the cyanobacteria took over the world and made the hyper Greenhouse climate cooler until Earth was basically experiencing its very first ice age that's a lot of accomplishment for what is basically mats of green goo excuse me sir have you learned of the glory of the Jews the ice would not become a permanent fixture by 2.7 billion years ago it had already completely receded I say already like we're not talking about 200 million years of cold this marks the beginning of the fourth and final era of the archaean the neo-archian and the cyanobacteria had made the world theirs evolving into new niches and covering different environments all over the globe and let's not get it twisted these guys were also the first organisms to adapt to dry land as well as the microbial mats spread across the continents and Islands it's thought that the land would actually start to turn green for the first time not with true plants yet but with microbial mats made up of trillions of tiny organisms who have managed to make the planet theirs and over the millions of years that followed the land masses would come together to form the first land that was large enough to be considered a supercontinent We Now call the this continent kennerland and it was well it was it was largely empty with the exception of the green goo slowly spreading across it almost like a moldy jelly just kind of slurking across there well even though there actually wasn't mold yet it's all quite beautiful isn't it it's amazing how sci-fi some of this stuff seems as I research these different times in Earth's past it's really easy to seem like we're just glossing over everything and to be honest we are and this is because now covering the first 50 of Earth's existence we're still lacking a lot of the fossil record to be able to accurately know everything that was going on during this Eon the fossils from the once proud cyanobacteria and Empire can now only be found in places like Shark Bay Australia they're called stromatolites and the top layers of these bulbs of rock are actually still alive that's right the cyanobacteria still continue to exist two and a half billion years after their reign as the microbial rulers of this world came to an end and cyanobacteria actually still exists today and a bunch of other niches including some kinds even living in our atmosphere floating in the air today and now we've come to the end of the archaean Eon as I said we are now already halfway home and from here things are going to start to get a little bit more complex but to recap our planet now has a moon a solid crust with abundant water on its surface the first two supercontinents have come together and been torn apart we have a climate that's starting to fluctuate and oxygen is becoming more and more abundant all the time and much of this was thanks to the mighty cyanobacterian Empire you know maybe I should just stay like this maybe I should just remain in the archaean and join a giant mass of Goo for the glory of the empire wait what am I saying sucks I have to try to get back to becoming a human I have to get back to my own time and after Consulting the Pokedex I think I know how I evolved into this form by breaching 1500 subscribers while being next to those hydrothermal vents at the end of the hadian remember so maybe that's the key maybe if I hit different Milestones of subscribers while in the right location I'll evolve to the next stage of my Evolution and eventually become human again okay so I know that this is something that you're probably all used to hearing all the time but this just became way more important if you made it to this point in the video and you're not already please for the love of God subscribe and if you are subscribed already share this or any of my other videos to other people so they can subscribe I need everyone's help to move forward through time and turn back into me again until I reach the next Milestone I have to stay here with this Colony otherwise I'll dry out and die please seriously these guys suck all they do is talk about the glory of the goo until then I'll just have to wait here take care everybody pray for me [Music] [Music] as we move through these ancient times in the past we've been making baby steps as the world's gone from a hellscaping capable of supporting life to something that shows some real potential but it has been slow going over 3 billion years has already passed since the formation of the earth and so far the only things currently living look like this but by the end of the archaean things were starting to at least slightly resemble our modern world at least comparatively speaking and with each step we move forward in time we're just a little bit closer to the world we know today this will be the last time that I cover an entire Eon in a single episode in this series because this video will take us all the way to just half a billion years ago and that's when everything finally starts to get interesting I feel like all this has just been the legwork to get us to the good stuff and now finally we're at the last step of setting the stage so now let's get into the proterozoic Eon and see what Transformations the planet and the life on it go through over the next two billion years and this one actually turned out to be a little bit more interesting than I expected because I actually didn't know a lot of the things that I ended up researching for this video we start things off with the Paleo proto-rosoic this was the longest of the three eras that make up this Eon and in fact it's actually the longest era in geological history covering from Two and a Half to 1.6 billion years ago but I think for several reasons it would actually be easier if instead of covering each era like I did the last time I just jumped from one major event to the next and the reasons why will become clear as we move forward and the first big thing that took place during this time is a direct result of events that took place in the archaean you see as the cyanobacteria spread and multiplied they took in carbon dioxide and excreted oxygen at first the increasing oxygen was kept in check by being absorbed by The increased iron that was in the oceans and as that happened oxygen did what oxygen does to iron and started to rust it as believed after several million years the end result was the oceans turning from a turquoise color to a d blood red the rusted iron eventually drifted down to the sea floor and eventually made up the iron oxide that we see in these stunning formations but there was a finite amount of iron in the oceans and as that dissipated the oxygen would start to build up to levels that the Earth had never seen before this may sound like a good thing to us but at that time the oxygen was actually toxic to pretty much everything that was alive and it makes sense if you think about it the organisms that lived at that time lived on a world where carbon dioxide and methane were more abundant than oxygen in fact there was almost no oxygen at all until the cyanobacteria started farting it out all over the world that's all the oxygen really was to these guys waste and just like us when we exhale carbon dioxide these gases that these organisms give off is normally toxic in large quantities in the modern world there's checks and balances to this because plants take in carbon dioxide and give off oxygen and animals do the opposite but during the early proterozoic there was nothing on Earth to take in oxygen and replace it with the new carbon dioxide so the noxious deadly cloud of oxygen kept building and this would be the end of the line for the mighty cyanobacterian Empire that's right Tim Tim you and the rest of your kind are destined to slowly suffocate on your own farts A fitting end if you ask me [Music] this would be the very first mass extinction that would ever happen on Earth also known as the great oxidation event or great oxidation catastrophe so the first great dying didn't start with a super volcano or a meteor but by the very air we breathed today and oxygen levels would continue to fluctuate throughout Earth's history this was just the first really massive jump that would ever take place and the Earth wasn't even done seemingly trying to cleanse itself of the goo infestation that it had contracted over the previous one and a half billion years because things were about to go from bad to worse remember how during the archaea neon the increase in oxygen led to global cooling and inevitably resulted in the first glaciation well as you may have guessed this may be foreshadowing for some things to come the world was cooling at a rapid rate as free oxygen built up in the atmosphere and there was nothing to counteract it at this point So eventually it resulted in a runaway glaciation that would go Way Beyond anything that Earth would see in the more recent past for over 200 million years the earth literally froze this time has been called the heronian glaciation or first snowball Earth yeah first so at this point we've literally seen the Earth transform from Mustafar to Hoth and this could have been how the story of life on Earth came to an end but sorry I'm not going out like that because thanks to all of you last week it's time for an upgrade freedom [Music] [Music] what no [Music] and come to think of it this actually brings me to the other big event that happened during this era the emergence of eukaryotes eukaryotes literally Encompass every Kingdom on earth that is multicellular as well as some unicellular organisms like protists now there's some debate on whether or not they truly did evolve during the Paleo protozoic but to me the fact that some of the cyanobacteria did manage to survive means it's likely that something had to start absorbing oxygen and releasing carbon dioxide at some point following the heroni and glaciation we come to a time that scientists have nicknamed the boring billion and yeah it's exactly what it sounds like after the first mass extinction brought on by oxygen pollution and dramatic climate change what was left when the world finally melted was a nutrient poor world that was kind of stagnant for an actual billion years starting at 1.8 billion years ago this time actually started to see a drop in oxygen once again and this allowed the cyanobacteria to take control again and this put us eukaryotes in a bit of a tough spot and this may be the first time that evolutionary pressure from another group of organisms started to affect the direction that Evolution would go you see Wii eukaryotes seem to be a little bit more adaptive than the cyanobacteria and it's believed that in the stale Waters of the boring billion our ancestors would Branch off into three very different paths the first would take a similar approach to the cyanobacteria and begin producing their own fuel from the Sun brought on by a photosynthesis since sunlight was in plentiful Supply and they didn't have to compete for it another would start breaking down the nutrients left inside the cells of dead organisms through decomposition and finally the last one would start getting its energy from consuming other organisms these are the most basic differences between the three main kingdoms of multicellular eukaryotes The Producers using photosynthesis would eventually become the plants the decomposers would become fungi and the consumers would become animals I should probably just mention real quick that there's way more than just three groups of eukaryotes but for the premise of this story those are the main three that we're going to to be focusing on so in a way the boring million turned out to be very important because during this time when the continents didn't even seem to be moving around a lot the eukaryotes started to diversify under the Second cyanobacterian Empire higher levels of methane given off by many of these microbes probably kept the water much warmer than during the heroni and glaciation but as a result the cyanobacteria continued to increase in population again and inevitably they would have the same impact on the earth a second time and now after all this time we've arrived at something truly Monumental somewhere along the way during the boring billion the different forms of life that evolved from the basil eukaryotes had become multicellular and around 760 million years ago the very first animal with this new scale would appear in the fossil record and it was a sponge it was called otavia and although these creatures didn't have a nervous digestive or circulatory system and they still don't they're still considered closer to an animal Than A fungi or a plant they get their energy from filtering particles out of the water through their pores and wait wait a minute Tim tin that's right I still live laughs foreign I don't know how you managed to survive the oxidation catastrophe and heronian glaciation but now we're about to get hit with a one-two punch of glaciations because your old friends won't stop multiplying and farting Icehouse gases into the atmosphere yeah okay maybe some volcanoes might have had something to do with it too but I'm still blaming you shut up Tim Tim the cryogenian was a period in the neoproterozoic that lasted from 720 to 635 million years ago it was called this because the world quite literally was in a constant state of being cryogenically frozen and thawed during the stretch of 85 million years the planet likely became a giant ball of ice on two separate occasions and after all this the world was in rough shape the cyanobacteria were still around but they were brought down from their status of rulers of the Earth for sure as we enter the ediacran we see that a new group was ready to claim dominance and somehow all three groups of eukaryotes managed to survive the glacial roller coaster and come out of it ready to expand into new forms is here that we first start to see a sea floor that's populated with animals and plants jellies first started becoming abundant at this time as well as possibly even the earliest basal cephalopods that's still debated topic though it's also when we see my new form sprigina first appear in the fossil record in Southwestern Australia and you might notice that it Bears a strong resemblance to a certain super widespread fossil that will appear in future episodes one thing that we are sure of though is that even though life was technically at its most complex as of yet it was still pretty simple soft-bodied and most of them not even having Brains it's still a pretty Far Cry from where we'll eventually end up but after being through every imaginable hellscape to get here it's pretty beautiful and now we've finally come to a big Turning Point we've traveled through the first three eons the hadian the archaean and the proterozoic and now we just have one left to go as we come to the dawn of the phanerozoic Eon and here is where we'll need to slow down quite a bit no longer flying through an entire Eon in a single episode next time we'll start to get a lot more interesting which is good since I don't actually know how much longer I could stretch out the story of the pre-cambrian all right Tim Tim come on I guess I'm stuck with you for now ultimate survive [Music] survive yuck have a good one everybody wait did I miss something oh in the last episode we discussed how during the proterozoic Eon the Earth froze into a giant snowball three different times these ends may have caused mass extinctions each time and the ones who survived would evolve into new species that would fill the niches left vacant by the ones who didn't make it as you can see I clearly missed one there's been fossil evidence found that suggests that at the end of the Ed Akron there was a fourth major glaciation and this would be the event that brought the entire Eon to a close there's a lot that still isn't known about this glaciation in fact some scientists already even convinced that it happened but if it did it would help explain one of the most dramatic and mysterious events in all of Earth's history it's thought to have made life increasingly difficult for many of the squishy guys that were around at that time as we move into the beginning of the Paleozoic Era remember that poll I did a couple weeks ago where I asked what era you all wanted me to focus on the most well here you go we finally actually made it to a time period complex enough to actually be covered by most major documentaries there's going to be a lot of changes moving forward from here and it all started with wait hey where'd timtim go Tim Tim what the crap are you doing some of the smartest squishies are trying to survive by hiding out in Burrows all right well you got to come out people apparently like seeing you for some reason [Music] whatever I'm going on without you then as the world recovered from this big freeze the life that managed to eke out a living by being hearty enough or by taking refuge in Burrows we're about to go through an amazing transformation around 541 million years ago as the oceans thawed out once again there would be a ton of new niches left open and the survivors would be ready to take advantage there was one thing missing from this puzzle of evolutionary forces one thing that made this event stand out more than just adaptive radiation like we've discussed before and that one thing would change everything from this time moving forward you see up until now the animals that we have discussed only got their energy and nutrients by passively feeding on photosynthetic organisms through filter feeding or slurping goo out of the sand but now for the very first time we see animals actively hunting and eating other animals and this would change the game forever suddenly it wasn't enough to Simply have the means of collecting food and a strategy to survive whatever the Earth was throwing at us now all of a sudden animals were out to get other animals and the ones who didn't figure out a way to respond to this were easy prey the first thing that every animal needed if they were going to survive in this competitive new ocean was a way to detect other animals around them and luckily there was already many different creatures that had basic light sensing organs on their heads this may have first evolved during one of the glaciations to find areas where the ice was thin enough for light to shine through and now it'll become the basis for the very first eyes and it seems that eyes may have actually evolved simultaneously in different unrelated groups this is a process called convergent evolution a term that you should remember because it's going to come up a lot as we move forward through time basically this is when two unrelated species evolve similar strategies or body types despite not being closely related but now that animals could see one another now that you need way to deal with each other there would be two major body plans that would really take off during this time or at least two major players that were going to be focusing on moving forward the first group would have a hard biomineralized layer of armor around the outside of their body this exoskeleton would protect them from attacks from carnivores and become a staple feature among the arthropods the other would develop a flexible dorsal cord that became the central point of the animal's nervous system while also allowing for greater maneuverability and speed this would become the template for every animal under the phylum chordata in other words the very first vertebrates thus making this one of our earliest ancestors this evolutionary arms race between animals trying to basically one-up one another would become the driving force behind the Cambrian explosion where the combination of all these factors would culminate in adaptive radiation going into overdrive from 541 to 516 million years ago is the time that we call the Cambrian explosion because of niches opening up and certain groups becoming Predators the oceans quickly filled with a menagerie of new more complex forms of life than anything we've ever seen before the basal vertebrate and arthropod body plans had started Reinventing themselves into every possible form nature could come up with and it is impossible for me to be able to list off every new type of creature that we see in the fossils from this time I feel like I could make several list videos talking about the different bizarre animals of this time the in the same vein as my Triassic weirdo video as this time started out it seems that a group of arthropods called the radio dance started to become one of the most dominant groups in many ways share a lot of similarities with shrimp and lobsters but maybe if you cross those with the facehuggers from the alien franchise the rest of the animal kingdom had to come up with something because squishy worms and sponges were not going to be enough some of the next things that we see evolve are what scientists call the small Shelly fauna these were things like the first gastropods brachiopods and trilobites it's impossible to say for sure if trilobites are actually the direct descendant of sprogena like I said in the Edie Akron I personally feel like there's something of a family resemblance but sprogena was soft-bodied more like a worm and definitely not like the pill bug-like Critters of the Cambrian and it's also believed that the worm-like creatures branched out into those primitive chordates and that's the path that I'm going to take this time because that's the path that will inevitably lead to me becoming human again all right [Music] [Music] well at least I have a spine one of the earliest known chordates appeared around 535 million years ago named High quick fees many think it shows characteristics of being the first ever fish and even though that's probably a broad generalization it's likely that it was at least very fish-like at only an inch long with a flexible nerve cord on its back this gave our ancestors a whole new strategy of avoiding arthropod predators echinoderms also evolved during the Cambrian as well an expansive group that encompasses starfish sea urchins sand dollars and sea cucumbers as well as a group called cranoids or sea lilies that look more like plants than animals at a surface level despite having a mineralized layer as well these guys pretty much all use the strategy of avoiding the notice of other animals and in addition to all these groups that would give rise to many of the different groups of animals that we see today there was also some really really bizarre stuff stuff like the Cambrian freak Show known as hallucigenia on the name like that you know this is going to be good this biological Erector Set is supposed to be some sort of stem velvet worm and one of the most outlandish things to come out of our planet's deep past it was originally believed that these tentacle spine things were legs some even thought that each one ended in a mouth that connected to a central stomach in the trunk but then in 1991 it was discovered that scientists were actually looking at this thing upside down seriously though can you even blame them it's now believed that these appendages serve the same purpose as every other major adaptation that we've talked about so far being some type of defensive spines that these creatures evolved in response to the growing threat of predation in in the shallow Coastal Seas of the Cambrian this was an astounding amount of biodiversity within just a few million years and we only have a small handful of snapshots to this time that allow us to learn about this pivotal part of our planet's past so there's no doubt that there was profoundly more creatures inhabiting the Earth that we still haven't discovered and in fact we may never discover all of them as we move into the middle Cambrian the oceans become full of life and many of these different groups that got their start in the Cambrian explosion start to specialize but life on Earth definitely looked very different than it does today there may have been a few groups here and there that looked somewhat familiar but for the most part this was an alien world the arthropods had further perfected the radiodont design as well as evolving into several other orders they came in all different shapes and sizes one of the most well-known families being a small five-eyed monster with a long trunk and a claw at the end of it for grabbing prey it was called opobinia and at only seven centimeters long it definitely wasn't the ruler of the Seas it was a very specialized Predator you see some creatures continued to use the strategy that it allowed them to survive the end of the ediacron to avoid detection by predators that being digging into the sand but if there was a food source to exploit you could bet that this group was ready to go for it this is believed to have been the reason and for opebinia's weaponized proboscis swimming along the sea floor searching for signs of worms and things and then snatching them before they could Escape it's actually believed that Predators like this were the main reason why hallucigenia evolved the way that it did and the trilobites mollusks cranoids and sponges continue to expand filling the warm sea floor with life it was actually around this time that the first corals evolved as well although we don't think that they were nearly as widespread as they would be in later periods we've still found evidence that they can trace their Beginnings to this time so what we are seeing now is a true complete biosphere form with just one piece missing the true apex predator and now leave it to the arthropods because they were going to take a form that would change the game for everything living in the Cambrian ocean and they did this by getting big like really big bicambrian animal standards up until now everything that we've talked about was Tiny But by comparison the massive anomalocaris was a monster it measured about a meter or three feet long and was undoubtedly filling the top predator role by taking a lot of the adaptations we've seen in earlier radio dots and fine-tuning them for the purposes of capturing and dispatching any prey it wanted and it seems to have definitely worked this animal is believed to have hunted and killed anything that its compound eyes could detect and it probably had the keenest vision of any animal at this time the long Spike the pendages on its face were its main weapon as well as its way for manipulating its surroundings the name anomalocaris literally means strange shrimp and it's actually one of the most well-known creatures from this time it's kind of become right up there with the trilobite as the poster Children of the Cambrian explosion I guess having a Pokemon made in your image can even bring a half billion year old giant shrimp monster into the Limelight and while all these new forms of invertebrate were evolving we chordates weren't remaining stagnant either we did however remain fairly small with the arthropods and other weird creatures filling most of the macro rolls in the shallow Seas it was probably a bit of a survival strategy honestly remaining smaller meant that we could remain faster and more maneuverable to avoid monsters like anomalocaris in later Cambrian we would see another widespread chordate appear on the scene [Music] oh Tim Tim good you survived timtim is now a bit of a mystery creature called a pikaya although being pretty basal it's believed that pikaya has most of the general characteristics of a basal chordate looking a little like a tiny hagfish or Lamprey with a flattened body and a distinct head on the front end it also had a pair of antennae-like tentacles that made it look more like some sort of gastropod than any vertebrate we know of today so who knows really the Cambrian is talked about as being the focal point of the evolution of Life on this planet and it really is every single group that exists today sees the beginnings of some direct origins in the bizarre alien creatures that existed here but there are countless others that for one reason or another didn't make it and as I said in my video about the Triassic weirdos these things appear weird to us today because of our perception so much about our world has changed between now and then that if I told someone who didn't know any better that this was a concept for a sci-fi fantasy world they would likely believe me there are a ton of animals that I didn't get to discuss in this video and as I said at the start it would be impossible to give all these different groups their due credit so I decided to talk about the most noteworthy ones that play the biggest part in future installments but for many animals their story ends here this is because as the Cambrian came to a close the world would be racked by a series of events that would cause several different drops in biodiversity and there's a lot of theories and debates about what caused this it could have been another round of glaciations or fluctuation and oxygen yet again or could have been a direct result to volcanic activity it's really not known for sure but for the animals that did survive whatever took place at the end of the Cambrian they would be setting the template for the remainder of the Paleozoic Era we left off 485 million years ago with an Extinction that brought the Cambrian to a close we lost a lot of the specialized radiodon apex predators like anomalocaris but many groups like The ever-enduring trilobite continued to press on and over the next 41 million years life will flourish and the torch will be passed to new players on the stage of our planet as we get into the ordovision period and what better way to kick off this new period in Earth's history than with another round of adaptive radiation to fill the void left by all the species who died out at the end of the Cambrian the interesting thing about looking at a map of what we think the continents looked like at this time is that it's literally the exact opposite of the world we know today today we see most of the joined land masses primarily across the Northern Hemisphere but during the ore division the entire northern half of the planet was covered in a massive ocean called the pantherlassic ocean the southern hemisphere was dotted by islands and smaller continents and one massive land mass that extended from the South Pole all the way to the Equator this supercontinent was called gondwana a massive slab of desert made up of what would eventually become South America Africa Antarctica Australia the Indian subcontinent zealandia and Arabia these continents were as far as we could tell pretty much Barren going into the ordovician there might have been colonies of cyanobacteria along the coast but especially Inland would have been entirely empty but all that was about to change because the very first forms of complex life we're about to make the leap from the ocean onto dry land this might seem like a small change but it is another major step in creating the world that we know today it was around this time that the very first terrestrial plants evolved now we haven't checked back in with the plants since during the proterozoic and that's because it seemed like they didn't really diversify much during the Cambrian mostly staying microbial in the form of algae and surviving in the shadow of the cyanobacteria but as they would start to move on to land at first they would kind of resemble tiny non-vascular plants like liverworts But as time went on and they adapted to life in the open air they would evolve to be able to produce the very first spores and it's from this very humble beginning that all complex plant life gets its start and who knows if plants didn't make this journey first maybe animal life would have never crawled out of the sea in the first place because after all beforehand and there really wasn't any reason to over the course of the ordovician animal life started to bounce back from what happened at the end of the Cambrian and by about the halfway point the diversity of Life seemed to have been back on the upswing many of the bizarre life that had existed previously had faded into Extinction but several others did manage to hang on and these were the ancestors of what was about to come next the radiodonts will always be able to claim the title of the first Super Predator but by the ordovician it seemed like those days were over however not all of them were completely wiped out the ones that survived would be the ones that took on a bit of a different strategy to feeding than the hyper carnivores we discussed in the last episode they would become filter feeders and take advantage of the bounty of microscopic organisms that had been filling the ocean since all the way back in the archaean maybe this became a more viable way to survive when many of the larger prey animals died out at the end of the Cambrian Period but this seems to have served them well because as a result of this new lifestyle tile the radiodonts were one of the first large animal groups to recover and beyond that they actually got even bigger than they were before egiro Cassis was among the largest at two meters long and twice the size of anomalocaris this is the earliest known giant filter feeder an evolutionary strategy that will be copied many times throughout Earth's history including by the mammals hundreds of millions of years later to create the largest member of that class of animals as well by about 467 million years ago the plants seemed to be back on track and was pretty well recovered from the Cambrian Extinction the trilobites were literally everywhere again the radiodons had settled into their new role as gentle filter feeding Crab Monsters and we vertebrates were hanging on trying our best to get by in an arthropod World things were actually going pretty well and it seems like things were only going to get better from here the oceans were once again flourishing with life what Tim Tim what do you want we have a situation what situation I was just saying how things were go oh well so much for that things were going well until about the halfway point of the ordovician when there seems to have been a sudden rapid increase in impacts from meteorites this was a result of things continuing to break up in the inner solar system at this time but what's really strange is despite some estimates saying that the Earth was experiencing a hundred times as many impacts compared to what we have today this doesn't seem directly connected to any mass extinctions in fact after this point life just kept Trucking along and became even more diverse wait [Music] what now [Music] [Music] all right then for millions of years at this point there have been chordates but we have lived in the shadow of the arthropod masters of the world as well as other invertebrates and for the most part the very first chordates more resembled hagfish and lamb praise than any other true bony fish I use the term chordate rather than vertebrate because at that time our ancestors didn't even have a true backbone yet but the next step in our Evolution would take place here in the ordovician with the appearance of my next form arandaspus now even though I wouldn't say that we're exactly ready to take over the world yet at just 15 centimeters or six inches long in terms of our evolutionary history these guys are a pretty big deal at this point it's believed that Aaron daspas was one of the first vertebrates as well as one of the first true fish even though it didn't have any jaw or fins yet it was probably able to get around using its tail similarly to a modern tadpole it was probably a filter feeder they stuck to the shallow water coastlines of gondwana and pretty much left the open oceans to the arthropods and to help with protecting themselves from any possible confrontations that they might have these early fish would develop protective armor on their heads in the front of their bodies a feature that might seem strange compared to fish today but it would prove a trait that would one day give our ancestors a Fighting Chance in the race for life and despite still being at something of a disadvantage the first fish were obviously doing something right since they even started to diversify into other species like sacabambasmus oh hey Tim Tim how's it going I think things are going pretty well we're better protecting than we've ever been and the only radiodonts that are left are basically filter feeding crab whales I feel like we might be forgetting something what do you mean well if they're ready to answer no longer a threat something else has to be driving our Evolution into these more defensive forms I hate when you're right release the carrot Krakens have you ever seen fossils that look like this normally clusters of multiple cone-shaped cylinders that polish up really nice they're one of the most common fossils that are collected besides ammonites and trilobites but a lot of people collect these without ever realizing what an important piece of the past they have these are the remains of the shells from one of the most prolific predators the world has seen up until this point an actively mobile carnivorous cephalopod called orthoceris now we talked briefly about how cephalopods may have gotten their start all the way back in the EDI Akron but it was kind of hard to say for sure because most cephalopods don't fossilize really well you know since they don't have any bones so there are a few Trace imprint fossils that we think might be early members of this group but we really can't say for sure that would all change with the evolution of the subclass nautiloydia the group of cephalopods that have a hard shell and includes everything from these guys to ammonites all the way up to Modern nautiluses today orthocerus is actually a broad term that refers to several different species ranging in size from Little Guys the size of your finger all the way up to the 4.5 meter or 15 foot sea monster that seemed like something from an Old Fisherman's tail these guys were the rulers of the open ocean taking over the position of apex predator in every corner of the globe their fossils have been found everywhere that there are Marine deposits from this time period and then on the ocean floor there was another new group of predators the very first uriptoids or sea scorpions despite the name these Marine arthropods are not true score beans but they're definitely closer to an arachnid than an insect and body plan because their bodies have two segments a head and an abdomen and I'll definitely be getting into them more as we go forward in time but it's definitely worth mentioning that the earliest species of uriptoid first appeared around the middle or division 467 million years ago called pentacopterus it also was a considerable size carnivore and it probably made the ocean floor every bit as dangerous as orthocaris made the open ocean and all these were probably the reasons why even after evolving the defensive armor of our early ancestors the first fish were still confined to the shallow coasts most of the large animal roles were still being filled by invertebrates leaving our ancestors confined to areas where we could better avoid them however as these giant cephalopods and arthropods became more and more specialized it may have left them at something of a disadvantage for what happened next as we go forward in time the periods of geological history are almost always concluded with a major drop or change in global biodiversity it's the reason why scientists looking at the fossil record are able to say that this is a point in time when one geological period ends and another begins so this will become a reoccurring theme in the history of the earth videos that being said however there are only five events that have led to such a catastrophic loss of life that they are actually considered one of the true mass extinctions these are normally defined as an event where 70 percent or more of the species on Earth are wiped out at that time and as we get into the late ordovician from 445 to 440 million years ago we come into the first of these great dyings this happened over the course of five million years because of wild swings in the global climate it started out with a glaciation that led to lower sea levels and cooler ocean temperatures this likely destroyed the habitats that the early fish relied on for protection from the invertebrates and had that been the end of it life would have likely quickly recovered but following the glaciation the climate would do a complete 180 and switch from an ice house to a greenhouse and this is when things would go to a critical point climate change will always lead to extinctions of the most specialized species but the more generalized ones we'll always manage to pull through but rapid climate change from one extreme to another can push things to the absolute limit and then things got even worse because as the oceans heated up the amount of oxygen in the water would start to plummet and that's never good for animal life which at this point still lived exclusively in the water but you know what it is good for cyanobacteria that's right it's time for the return of the goo as the cyanobacteria spread across the anoxic oceans of the Leda or division they literally choked every Marine ecosystem and by the end of this roller coaster of events a staggering 85 of the species on Earth were wiped out making this Extinction event well within the qualifications of one of the big five mass extinctions in fact despite this one being one of the least well known it's actually one of the worst as the ordovician comes to a close we're left with a truly sick planet and there will be no Swift explosive comeback that we've seen before this level of cataclysm will take some time to recover from but we still have about 444 million years to go to get back to the present so life will inevitably find a way so the ordovician ended on something of a depressing note for sure complex life had been doing really well for millions of years ever since the Cambrian explosion and we were starting to see some really interesting ecosystems at least the Marine ones Hell by the end of the ordovician even the ancestral vertebrates were starting to be passable as true fish but all that progress nearly came to a screeching hole when the planet went through a bit of a roller coaster of climatic extremes first it got cold not quite on the same level of another snowball Earth but still cold enough to be considered an Ice Age then it swung in the opposite direction and got warm and stagnant oxygen levels plummeted and the world's oceans were once again overwhelmed by cyanobacteria [Music] these guys are irritating yeah tell me about it but they're also pissed [Music] all right well while you eat that I think it's time that we move forward as we leave the ordovician behind we're left with a world with only around 15 of the biodiversity it once had life was gonna have to take some time to recover from the first major bottleneck since things became more complex than this and that's what it seems like was happening during the roughly 25 million years that followed in the solorian period a comparatively short time in geologic terms but definitely a very significant one where the ancestors of everything alive today start to bounce back in the wake of so much Devastation the warm climate that caused the glaciers to retreat to the South polar region of gondwana continued to get even warmer and this is how it would remain for the duration of this entire period the thing that we tend to forget about climate change is that it's a constant factor in the story of life on Earth global warming as well as global cooling can have equally devastating effects because it's a shift from what the current organisms living at the time are adapted to anytime that you see long periods of time where the climate either Remains the Same or continues intensifying in the same direction you will see animals adapt to be more and more specialized to those conditions so despite the fact that the warming climate at the end of the ordovician was one of the factors that led to a mass extinction the animals that did survive did so because they were adaptable generalists who were able to make a living in the new hot lower oxygen world and as sea levels began to rise rivers and lakes would inundate date the coastal areas of the supercontinent gondwana as well as a newly forming Euro America in the north and this would become the perfect home for some larger life forms during the previous period I spoke about how a few different species of plants were able to have colonize the land but they remained pretty small and simple this would all change around 425 million years ago when the plants finally gained vascular tissues this was the first Great Leap Forward in plant Evolution it allowed them to have a more stable structure and grow to Greater sizes as well as distribute water and nutrients throughout the plant they were now capable of reaching up to the sky to access more of the sun's energy and along the streams and rivers of solorian gondwana and Euro America these early plants spread out even farther than their ancestors species like cooksonia were some of the first to Pioneer this new strategy forming what could arguably be called one of the first examples of a forest biome but they wouldn't be the tallest organisms in these forests that honor instead would go to an entirely different Kingdom of organisms fungi yes the very first forests on Earth were made up of giant tree trunk-like fungus called prototxtites now technically fungus had been expanding onto land ever since the order Vision alongside the plants but by about 420 million years ago they had become massive eight meter tall trees making them the largest organisms on Earth up to that point this was the first time there was a really well-established terrestrial ecosystem fueled by the greenhouse climate and constant rain it was just one thing missing but that wouldn't be for long [Music] as life on land was finally getting its proper start in the Towering fungal forests life in the ocean was on the slow road to recovery as far as we know the large nautiloid Predators like orthocerus were some of the hardest hit by the ordovician extinction some species of this group did survive like cephusaris but they appear to have been less dominant going forward and this left the niche of top predator open once again and now with the expansion of new types of corals and cranoids exploding in diversity new marine ecosystems were beginning to open up something a little more similar to the coral reefs that we would know today and for the very first time the chordates were finally ready to fight for the role of apex predator the thing is we needed something to be able you know eat something besides goo as well as a hard skeleton the thing that would actually give us the name vertebrates and you know what that means this should be good [Music] [Music] meep [Music] it was around this time that these early true fish started to Branch into several different forms it all started with the evolution of movable jaws and once that happened vertebrates were finally able to take advantage of all the different food sources that had previously only been available to arthropods and cephalopods the jawed fish split into three distinct groups the cartilageless fish whose skeletons were made of a more flexible cartilage the bony fish with the skeletons made of bone and the armored fish which took a strategy from the arthropods and had a partly external bony skeleton which helped with defense and then from there the bony fish would split into the ray finned fish and the lobefin fish it was really an age of fish diversification and this is one of my new form Goyo oyoranos first appeared the earliest lobe Finn fish we currently know what's special about these fish in particular is the fact that the fins are actually mounted to the pectoral and pelvic girdles this allows for greater range of motion and possibly even the ability to bear weight on them the Seas were starting to fill with life once again but the thing is most of the fish still remained pretty small Goyo just measuring around 30 centimeters long but that was because despite our explosive variety that came in about 10 million years we were not alone in fact the fish were still far from the dominant group during the solarian ah crap they don't have teeth like this we still haven't taken over well there was one but it wasn't Andrea lepis sorry the only one that even came close was the monster fish Mega mastics a lobe Finn fish that grew to a meter long making it the largest vertebrate on Earth during this time you're like a third of that size plus there's still another group of animals that I still need to cover from the solorian another Survivor from the order Vision Extinction that would become the ruler of these warm shallow Seas it's more big bugs isn't it oh yes ever since the Cambrian the arthropods have been major competitors for dominance in the world's oceans in tier Zoo terms they were top builds in the game the first huge successes for them came in the form of trilobites and radiodonts there were many other groups that branched off along the way the trilobites were still going strong and even bouncing back during the solarian however the radiodonts were starting to run out of steam at this point and as the ordovician gave way to the solorian a new group of arthropods started to take that top predator role the eruptorids we already talked about those first species like pentacopterus and how they were a threat to the early vertebrates during the ordovician but the thing is they had a lot of competition from the large cephalopods so they struggled to get out of the roll of Bottom Feeders and although the carrot Krakens weren't entirely gone they were definitely less abundant than they used to be and just like we see time and again there will always be something waiting to take advantage of open niches it was finally the sea scorpions time and they would split into two different body plans and survival strategies the Stylo neri-esque sea scorpions which remain smaller and kept to the ocean floor Scavenging on whatever they could and the europt arena sea scorpions who took a more active hunting approach they had paddle-like arms that allowed them to swim through open water which gave them the edge they needed to become the kings of the pantheolastic Seas this one group evolved into several different species but by a wide margin the most common was euripterous which makes up up to 95 of the sea scorpion fossils found from this time I even own one now euripterus was a modestly sized little horror at between 13 and 60 centimeters long but one genus of sea scorpions that stood Out Among the rest was the Monstrous Terry godis these guys were the apex predators of the solorian they grew to nearly three meters long and had grasping claws that actually make them look more like the true scorpions that they share their name with it's actually believed that these arthropod Predators evolved in response to the explosion and fish diversity it was going on across the globe it appeared to almost be an evolutionary arms race between the two groups and with things like Terry godis megamastics and a handful of remaining squid around the oceans were getting pretty scary again if you were small it was beneficial for you to try to avoid these sea monsters and the best way to do that would be to enter the New Frontier a world where the only giant organisms was giant mushrooms that's where the future is the end of the solorian was not nearly as devastating as the end of most periods in Earth's history there were a few notable things that happened though the climate that had held on for 25 million years was about to go from warm to hot and as a result now there was no ice at all at the poles and now tectonic activity was starting to ramp up the last pieces of Euro America were starting to come together as Siberia pushed into the North American Plate and this formed a new Giant mountain range but currently there was nothing that could live there all the plants and fungus that currently lived on land still had to stick close to the water leaving the interior of both supercontinents a massive desert but it's in this moment that our world is the most alive that it has been so far and among the giant mushrooms and Tiny plants there was a chance that you might actually see movement for the very first time because to survive the onslaught of the fish and sea scorpions competing beneath the waves a few groups of small arthropods have managed to make the transition into living at least part of the time on land it probably started small with some different kinds of uriptoids crawling up onto land to lay their eggs far away from everything else but by the time we get to the end of the solorian we see the first signs of fully terrestrial animals the first pioneers being millipedes and possibly even the true arachnid cousins of the Seas scorpions for the moment at least it was a bug's World however in the Seas the competition between vertebrates and arthropods was about to intensify going forward things are going to get a lot more interesting in my opinion at least and actually the next three periods were some of the most requested times for me to cover even before I started to do these deep dives into history of the earth and considering how little publicity the Paleozoic gets and how interesting life gets during this time I can see why but for now I must leave you on this beautiful world of giant mushroom trees scorpions the size of crocodiles and Tintin looking like a creature cooked up by Jim Henson on cough syrup hey have a good one everybody following the recovery from the ordovician mass extinction we started to see our world develop a lot of ecosystems that at least Loosely resembled some of what we see today in the Seas complex food webs of arthropods and fish were starting to thrive and on land we were starting to see something akin to the very first forests but instead of trees the tallest organisms were strange forms of fungus that evolved in the eight meter tall pillars and the true plants remaining closer to the forest floor the relatively stable climate of the solarian allowed life the chance to bounce back but by the beginning of the devonian competition was about to pick up all culminating into the first really big evolutionary arms race on one side we had the arthropods who had dominated most marine ecosystems since the Cambrian explosion and on the other was the early vertebrae who had been in a bit of a disadvantage without armored bodies that came in the form of exoskeletons but ever since the evolution of Jaws our ancestors were at least able to fight back and around 419 million years ago as the solarian ended in the devonian began a surprising thing started to happen we were about to start winning because at least one group of fish were starting to become every bit as defensive as the arthropods and this would also give them the tools that they needed to become the apex predators in this increasingly bountiful world [Music] I cannot help you but you know what can help you a fish with a guillotine for a face huh you may have a point maybe we should come up with a new strategy to get through this period but we have a ton to get into before we even get into that so let's dive into the devonian as I stated in the last episode The solarian was a pretty stable time in geologic and climactic terms during the devonian gondwana would remain as the largest landmass on the planet over the 61 million years it would start to move slightly northwestward but still remaining entirely in the southern hemisphere but several smaller land masses had broken off of both gondwana and your America and kind of formed a closed off Seaway from the massive pantheolastic ocean we call it the Paleo tetha C and it along with the a narrow Seaway called the right ocean would become the stage of a lot of noteworthy things that were about to start happening during this time as far as the climate goes the devonian continued in a relatively warm Trend but there was a little more fluctuation than before there probably was no ice at the poles but because there was no ice sea levels were very high leading to an abundance of warm shallow Marine habitats this was something that had been slowly building up for a while but with more and more shallow Seas opening up more different kinds of organisms can move in and adapt in general shallow seas are comparatively more productive than deep oceans because sunlight has an easier time penetrating shallow water this allows photosynthetic organisms to spread which makes up the base of any food web we saw all that get started in the solorian but now after so long with such stable conditions many different groups were going to start struggling for dominance and the ones that make the cut would be the ones that learned to take advantage of the new biomes that were becoming available today coral reefs support countless different species of animals they're basically the Marine equivalent of tropical rainforests in terms of biodiversity and corals have existed in some form ever since the Cambrian explosion but they weren't building up the giant calcified structures that we would think of today at least not yet the thing about corals is they've always been really picky about things like ocean temperature and oxygen level and all that and throughout the solarian and going into the devonian the water temperature was too warm for corals to spread into full-blown wreaths but there was another organism capable of forming reefs during this time the very same things that have stuck around ever since the archaean the cyanobacteria ever since that now distant time some species of Goo had formed colonies and built up over time into structures called stromatolites these would become the basis for some of the very first reefs and likely had been a ecosystem that benefited life for millions of years but as we get into the middle devonian the climate and ocean temperatures would drop slightly now it wasn't a lot but it was enough to make a big difference for the rugos corals that were around at the time because even though corals are picky once conditions are favorable they spread much faster than the cyanobacteria can form store metalites so by the middle devonian we see a shift to the first large coral reefs that have been on Earth since they were largely wiped out by the ordovician extinction these reefs were populated by many creatures that we would consider familiar at this point in our journey as well as a few new faces the trilobite States had fully recovered from their hit that they took at the end of the ordovician as well covering the sea floor like the Invincible little Troopers they are but in the open water column a new group of animals was going to appear that was one day going to become an even more common piece of the fossil record than the indestructible pill bugs it would be coming from a group that famously doesn't fossilize very well this is when the very first ammonites appeared ammonites are cephalopods so these guys were distant descendants of the Monstrous carrot Krakens that ruled during the ordovician there were still carnivorous like all other cephalopods but it seems like the title of apex predator was not within their reach especially when you consider how much competition for that title was started to ramp up throughout the entire solorian period one group of animals was King the eryterids were still going strong by the beginning of the devonian and environmentally there didn't seem to be very much to keep them down but despite this we do see a steep drop off in the sea scorpion populations at this time scientists believe that this is because of new competition that would raise the stakes in the world's oceans up until now jawless fish were the most common fish on Earth but the vertebrates did manage to Branch off into a couple different variations leading up into the devonian and that was all laying the groundwork for what was to come it was now time for two groups to rise up and Dethrone the arthropods this is when the fish with skeletons comprised of flexible cartilage started to become more active Predators the very earliest sharks or cladodons and you would think that the first appearance of sharks would be a pretty big deal for marine ecosystems but really really they were kind of playing second fiddle to the real monsters of this time the second group of fish to rise up the ones with bony armor on the outside this group is called the placoderms and they are unlike any fish that we have today they had Jaws but technically no teeth at least not in the same sense as you would think instead the armored plates that made up the skulls formed a blade-like structure sort of similar to a beak and with these tools and defenses this group of fish didn't just break out as top predators they started to explode into every possible Niche they could even the smaller species were so defensive that the only things that could effectively feed on them were bigger placoderms and that brings me to the thing that I know you all wanted me to talk about the biggest and baddest of the placoderms Dunkleosteus this nearly 9 meter four ton monster eat who are you it's me Clinton William from the future and I came back to make a correction because for years everyone has been depicting the guillotine mouth Dunkleosteus to look like this with a kind of shark-like body measuring up to what'd you say nine meters but the thing is the only remains in this placoderm that have ever been found are just skulls and Jaws so for years this design was simply a guess based on the body shapes that we knew of from more complete fish in this family but recently new research has been done showing a direct correlation between the total body length and the measurement from the eye of the fish to the back of the gills this metric has been tested and confirmed with every fish species that they've tried it on living or extinct and by this metric dunkleoste is probably measured around half of what we previously thought however we still don't know exactly what its body looked like it could have looked like this or like this but personally my vote is that it probably look like this oh well I see Tim Tim still an idiot in the future but either way even at this reduced size Dunkleosteus still would have been the top predator of the devonian Seas its bite force was focused into the front of the Fang tips and measured 80 000 PSI I I actually had to double check this for context the maximum estimated bite force of a Nile crocodile is around 5000 PSI so this thing could bite 16 times harder than a large crocodile and it basically had a guillotine in its mouth with this thing at the top of the food chain there really is no wonder why there was a sudden turn to more defensive forms arthropods were armored like the placoderms but the way these new fish Predators were armored in the front with powerful muscled tails in the back in a flexible spine they were doing everything we had seen in other parts of the animal kingdom only better and since Predators Drive the evolution of prey by removing the individuals who don't cut it from the population everything else on Earth was starting to evolve into the placoderms world the style of Nuria sea scorpions would manage to Hold On by not competing directly but unfortunately the erupt Arena sea scorpions were just going to fall victim to this power shift it seems like if you couldn't keep up the best survival strategy was to get away and avoid the armored fish at all costs and it would be this pressure that drives one of the most momentous events in the history of life on Earth one small step for fish [Music] one giant leap for vertebrate kind [Music] with life in the oceans becoming so dangerous it's not surprising to think that if there was an alternative available some organisms were going to go for it and meanwhile on land as more complex rooted plants started to evolve this allowed soils to stabilize for the first time and the plants started to grow larger this would change the dynamic of terrestrial ecosystems forever previously in the solorian the giant fungus like prototxtites were the largest things on land but as the devonium went on they started to slowly get replaced by the very first large plants it's unknown exactly why the fungal trees were failing while large plants were managing to survive but one theory is that plants were better equipped to defend against being preyed on by arthropods which there was starting to become a considerable variety things like centipedes and millipedes were common and the arachnids like true scorpions mites and a strange group that looked like a cross between a tick or a Mite and a spider called the tragano tarbids had begun to diversify throughout the solorian the invertebrates were left unchallenged on the land but now it was time for that to change as the plants spread across the land even far away from waterways along the coasts you would find the very first vertebrates making the leap onto land the tetrapods they evolved from the lobe-finned fish that to be honest were struggling just as much to deal with the armored fish as well everything else but this would give them the chance to survive now this might seem like very humble beginnings and well it is these things were basically something between a salamander and a mud skipper but their success is undeniable different species started popping up all over the devonian world using their limbs that were still something in between fins and feet which in different species like tiktolic and archeostega had eight digits on each they were able to haul themselves up out of the reach of the placoderms and in this new world they would likely become Predators with eyes positioned on the top of their heads and sharp needle-like teeth it's thought that they were the very first animals to make use of the Ambush hunting at the water's edge strategy that we would see many times in the future these animals are a big deal to our understanding of life because because every single organism that lives today and has a backbone and lives on land can trace their ancestry to the pioneering creatures of this time although they were still tied to the water especially to reproduce this was the blueprint of things to come and it was lucky that we made this leap when we did because as we come to the end of the devonian the world's oceans were about to hit hard times once again the late devonian Extinction is not very well understood a few things we can say however is one it doesn't appear to have been a single event but rather multiple events that caused it and two the effects were much more severe in the oceans than on land or in freshwater ecosystems one theory is that an asteroid impact may have been to blame for part of it but to many scientists this doesn't really check out for one thing so far there's been no impact sight found but that doesn't really matter because 350 million years has passed since then and there wouldn't be that much of a crater with that much time to erode but the fact is that an asteroid impact would have equal effect on both land and sea so most people think that it must have been an event that was specific to the oceans the most popular theory is that something caused the oxygen levels in the oceans to plummet this would have an adverse effect on many of the different groups that Rose the dominance over the 61 million year period break odds trilobites and ammonites would all be hit hard by this but they would pull through but the worst effects were to the Marine vertebrates as much as 96 percent of them were wiped out in the last few million years of the devonian the Bony and cartilagulus fish managed to hang on but unfortunately the armored placoderms were not so lucky these animals were extremely well adapted to be the kings of the oceans and they were the first vertebrates to take control away from the inverts and although their rule was short when you look at the total story of life on Earth it showed for the first time that the body plan of an internal skeleton is not inherently inferior to an exoskeleton but once again it also shows that whenever a catastrophic change in the world takes place it's the ones on top that have the most to lose whenever there's a major ecosystem collapse the animals at the top of the food chain are normally the ones that are going to struggle the most to get what they need to survive whatever the cause of the die off at the end of the devonian are direct ancestors like tiktalik were relatively unaffected in fact as this period came to a close they were actually becoming more abundant than ever and now the land was growing even more hospitable and trees started to spread across the globe and eventually from pole to pole would be covered in an endless tropical forest and that would be the stage for the next chapter in The Odyssey of life so getting back to our Journey Through Time the state of Life at the end of the devonian was very different depending on where you were standing if you were one of the pioneers of the land the world was pretty nice forests were spreading out from the rivers and marshes and there was getting to be more and more opportunity here all the time but if you lived exclusively in the ocean well you're probably lucky to be alive the world's oceans had been hit by a mass extinction that only left around four percent of the animals that were thriving previously but the land didn't seem to be having these issues I say good riddance well that's rude everything keeps trying to eat me you think that's gonna stop just because we're on land [Music] so basically as we go into the Carboniferous there was once again a power vacuum in both the marine and terrestrial environments all over the world for two totally different reasons in the ocean life is bouncing back from the death of the armored fish and many other dominant groups and on land the spread of the massive Global Forest would open up new opportunities for those who were able to adapt this Forest would become so all-encompassing that Not only would it have a very unique effect on our planet and its inhabitants at this time but it would even affect our modern world in a critical way which is wild to think about considering this period began 358 million years ago I've been looking forward to this one so let's dive into the Carboniferous jungles during the Carboniferous the world was undergoing more drastic changes than ever before gondwana was slowly drifting Northwest on a collision course with Euro America and Siberia and the small chain of islands that started to form to the northeast of the supercontinent during the devonian had grown into a small land mass in its own right it's impossible to tell from looking at it but this small island continent will one day make up part of China the formation of this land mass further isolated the panthelassic and paleo tethus oceans from one another but the real massive change was when this little blue and brown marble finally started to change into a blue and green marble plants fungi cyanobacteria and a few animals had been able to establish themselves on land in some capacity leading up to this time but generally speaking the first pioneers were restricted to staying close to the waterways but this was all about to change because in the hot humid climate of the early Carboniferous there was is about to be an explosion of biodiversity every bit as impressive as the Cambrian or ordovician explosions that we saw in the oceans of the past and the first organisms that we see this with would be the plants horsetails Club mosses ferns primitive conifers and cycads all get their start here and that's just the ones that we're familiar with today this jungle would spread out from the rivers and ocean and cover the entire globe in an endless Tree Line unlike anything we've seen up until now and this would have a profound impact on the world in several ways for one thing the presence of all this plant life also meant a massive increase in oxygen and anytime that we see big changes in the air usually that makes for big changes for everything else as we've seen before for one thing it started to change the climate we start to see a cooling Trend by the middle Carboniferous that leads to an ice cap forming at the south pole for the first time in millions of years probably the only part of the land that wasn't covered in vegetation as this runaway effect continued on generations of plants would come and go and old vegetation would fall to the forest floor either just through natural processes or much more likely forest fires that would be taking place as an extra consequence of all the oxygen in the atmosphere and these plants spent their entire lives taking in CO2 and expelling O2 leaving the sea or carbon locked in their tissues and over the 60 million years of this period this would be something that would be locked away in the Earth forever so slightly off topic this is something that I hear from people all the time people who say the use of fossil fuels means that we're using a liquefied fossil remains of dinosaurs are pretty much dead wrong the overwhelming majority of the fossil fuels in use today originally are dated back to the coal beds of this time 100 million years before the first dinosaur or ever existed in fact there's so much carbon in the deposits all over the world from this time that this is the inspiration behind the naming of this entire period the Carboniferous checking back in with the oceans as I said before the state that it was kind of left in by the end of the devonian was pretty sad but of course as always extinctions leave opportunities open for the survivors to expand into new forms and in the warm Waters of the early Carboniferous there was about to be another Mass diversification echinoderms cranoids gastropods and bivalves all managed to pull through and the cephalopods were still hanging on as well but by now the straight and curved shelled varieties had died out what was left was the ammonites and the true nautiloids which despite animals like the modern Nautilus bearing a resemblance to ammonites this is how far back the two groups actually separated the trilobites were still around but unfortunately they were definitely on the decline compared to previous periods they may have been starting to get out competed by other forms of arthropods like the true Crustaceans this seems to Mark The End of the invertebrates reign as the rulers of the oceans as the fish despite losing 96 percent of their biodiversity by the end of the devonian were about to take control for themselves and this time it would be in a much more familiar form this was the chondrithian's time to rule the group of fish that among other things would lead to the shark now this line of fish has been around since all the way back in the solorian but they had remained smaller and relied on their cartilage-based skeletons to allow them to be faster and evade the armored monsters that were filling the dominant roles but now after the fall of the europterids and placoderms it was the perfect moment for them to become the masters of the sea the condrikthians radiated into several different groups the most successful being a different group from the true sharks called the Eugenio dantids these creatures had some very interesting face in headgear but otherwise a lot of them were starting to be very similar similar to Modern sharks for example there's the early species called cassiotis this was one of the basial members of the group and although they would survive for quite a long time it would also give rise to several other noteworthy creatures like the slightly more unique ornithopryon which in itself would be the direct ancestor to probably the most well-known member of this order in the future the fish quickly bounced back as the Carboniferous went on some groups even managing to spread into freshwater ecosystems putting them in close proximity of the New World opening up in the air above in this world would be a world of swamp monsters and giant bugs as oxygen levels skyrocketed and the land was covered in tropical forests and swamps the vertebrates and arthropods were about to take their age-old evolutionary arms race to the New Frontier it was at this time that some of our tetrapod ancestors started to become true amphibians finally developing the Finns and fin-like legs into proper weight-bearing limbs the earliest example of this was with a creature called Peter peas a name which means Peter's foot who's Peter this one meter long creature is very important because it's currently thought to be the evolutionary link between the tetrapods that were more similar to lobe-fin fish and the true amphibians and also because fossils of land animals from the early Carboniferous are extremely rare So for all we know there might have been a ton of other animals like this crawling around But as time goes on we do see a lot of other strange types of amphibian in the later stages some of them even had their shiny new legs shrink and become more snake-like like like this thing called Colorado Britain and then someone in the opposite direction and further developed their limbs for walking on land like Tudy Tanis and we even have some major Predators coming from this group like anthracosaurus measuring up to three meters long and is also known as the reptile like amphibians but the most dominant of all was a group of ruling amphibians called the temnospondals large species like eerieops may have grown up to three meters long and 200 kilograms probably hunting somewhat similar to once again crocodilians these were some of the most powerful vertebrates on the land but unfortunately not only did our arthropod competitors have a head start colonizing the land but the way that they were designed was going to give them an edge in this High oxygen environment you see unlike terrestrial vertebrates which have two lungs and breathe through their nose and throat terrestrial arthropods have openings across their bodies that connect to the tissues that need oxygen that's why today there's an upper limit to the maximum size that arthropods can reach because in today's atmospheric oxygen level of 21 bugs can't grow to three four meters long but if you crank the oxygen up to say 35 percent as a it was in the Carboniferous suddenly the limit has been raised in these jungles there were giant bugs like the terrifying 70 centimeter long pulmona Scorpius yes this was a scorpion the length of a human arm the largest any terrestrial arachnid would ever grow and we also see the largest land invertebrate to ever exist the herbivorous arthroplora a millipede that could grow up to two and a half meters long and the bugs would even take to the skies for the first time during this period most well known of which being the falcon-sized meganera a relative of modern dragonflies and damselflies and among all these monsters in the tropical landscape of the Carboniferous there was even a relic of a bygone time lurking in the swamps the one and a half meter long campio cephalus the very last of the sea scorpions despite this guy's pedigree for predation the europter its days were long past them at this point basically nothing more than an oversized horseshoe crab probably using its shovel-shaped body to push through the muck and Scavenging on whatever it could a humble end to what was once the top predator of the oceans with all these strange creatures around the Carboniferous swamps was likely a very dangerous place for many of the smaller vertebrates running around our direct tetrapod ancestors were constantly having to hide from giant carnivorous amphibians and bugs setting aside all your shenanigans I think we're going to need a new strategy to survive this jungle it's time for us to free ourselves from the swamp here we go again [Music] finally a mammal adjacent foreign Carboniferous there was a major change on the horizon for our ancestors you see despite the fact that the forests were spreading far inland from the rivers and swamps we were not able to do the same this is because the early tetrapods were still dependent on the water we could breathe air but our skin was not capable of holding water so if we spent too much time on dry land we ran the risk of drying out and our eggs were still completely dependent on the water so for a while we were kind of stuck but these were all issues that we were going to overcome around 320 million years ago as some of the amphibious tetrapods became the very first amniotes their thicker skin would protect them from drying out and now their eggs would have a hard membrane or shell that would make them less physically fragile as well as allow them to be laid outside of the water we were now truly all-terrain organisms and with these new adaptations the amniotes spread across the world diversifying into two major clades the sauropsids and the synapsids despite these early members of this order looking very similar to each other inside there were differences that would be the first signs of things that would become defining features of the two clades these can best be seen in the skulls and teeth while the skulls of seropsids had two openings besides the eye socket synapsids only had one the earliest known sauropsid was a tiny lizard-like animal called casinuria this was the earliest animal to have claws on its fingers yet another adaptation that would be massively useful for future generations and despite it looking very lizard-like these guys actually are not true lizards actual lizards wouldn't evolve for several million years and the earliest of the synapsids would be my new form archeothris who again looks like a tiny lizard but was actually more advanced than the early soreopsids it had stronger jaws than most animals at the time for this size and actually had a pronounced canine tooth that was another thing that started to separate the soreopsids from the synapsids is that the synapsids tended to have different kinds of teeth in their mouth at least much more pronounced differences than what we saw in the seropsids now despite all the amnios looking pretty similar early on they would explode over the next 20 million years and once again be able to fight back against the giant bugs in the amphibians hiding in the swamp and they would get larger too with herbivores like desmetodon and carnivores like limnosculus despite this period often being referred to as either the age of amphibians or the age of giant bugs depending on which side you're on I guess by the end of the period the amniotes were making a decent case for themselves as they managed to go anywhere that they wanted to it was a good thing that they did too because as gondwana and your America came together there was going to be a lot of changes that will spell the end of the global rainforest as more and more CO2 was absorbed by the global rainforest this steadily continued to have an effect on the climate as well through most of the Carboniferous things remained pretty warm and humid just the way the amphibians like it and the oxygen levels kept getting higher just the way the giant bugs liked it the problem was that this was creating a cycle that inevitably could not sustain itself because CO2 is also a greenhouse gas needed to keep the warm temperatures up so the more carbon got locked in cold deposits it did start to get cooler the glaciers over the South Pole started to expand this dropped the sea level and made the climate drier and then as things were already starting to get dicey gondwana Siberia and Euro America would finally come together to form the massive supercontinent known as Pangea and this would be the Tipping Point as the world continued to get cooler and drier suddenly it became much more difficult for rain clouds to carry water from the ocean to the interior of the continent and Without Rain there can be no rain forests this is known as the Carboniferous rainforest collapse and this would be the event that brings this period to an end as the southern region became locked in ice the swamps and rainforests started to disappear this would spell the end for many of the dominant amphibians and another consequence would be that the oxygen levels would no longer be able to hold at such a high percentage so although insects as a whole would be fine this would also be the end of the giant bugs a few tempta spondyls would manage to hang on in the coastal areas near the equator but ironically our ancestors were doing quite okay and now in this new dry world the amniotes were going to take over especially the synapsids ah Tim Tim I see you followed me down the path of the stem mammal is the coast clear yep most of the bugs in the swamp monsters are all dead timtim here has evolved into another synapsid called aerosaurus and I can't help but notice that you've picked a form that's particularly good at running that's right and I now have very well adapted teeth for hunting so now I will be the Predator things are starting to look up for us for sure despite all that we've seen up until now somehow we've managed to not only survive but come out on top and with all that carbon safely locked away underground the climate will remain nice and cool after all it's not like some inquisitive Little Monkeys gonna come along and start burning it as fuel and releasing all those greenhouse gases into the air because that would be insane but for now we come to the tail end of the Paleozoic Era it's truly staggering how much time this Series has traversed so far from cyanobacteria first forming from the earliest building blocks of DNA to the tiny microbial ancestors of all the major phylums on Earth we covered the rise of complex multicellular animals in the ediacran and the Cambrian explosion and ever since then it has seemed like the torch of world domination has been passed every couple of million years starting in the oceans with the radiodonts to the cephalopods to the eruptorids to the placoderms and all this conflict beneath the waves had led to different groups slowly colonizing the land and by the time we get to the Carboniferous we see our very first thriving terrestrial Global ecosystem in the form of a rainforest that extended from pole to pole but every time that life started to become well established something would happen that would seem to be like nature hitting the reset button climate the atmosphere or the continents moving around has always seemed to shuffle the cards and every time new animals would end up on top and most recently it seemed like our ancestors were finally being dealt a good hand which brings us to 298 million years ago as the world started to become cooler and drier for the quickly diversifying amniotes this was their time as we begin our journey through the Permian going into the Permian the continents were continuing on the same path that they had started on millions of years before and this would lead to several changes to both the climate and the landscape for one thing the land masses of gondwana and Euro America had finally come together this resulted in the formation of mountain ranges where the two plates met the tectonic forces generated by this were likely some of the most powerful scene on Earth since the hadian and archaeanions now one thing about large mountain ranges is that they can have a very drastic effect on the regional climate because if a mountain range becomes tall enough it can literally block moisture from getting past it that's why when you look at a map oftentimes you'll see that on one side of the mountain range there will be dense forests while on the opposite side you'll see drier more arid conditions this is called the rain shadow effect and in a situation where there was already a limited amount of water making into the interior of the continent to begin with this would create a situation where there would be two drastically different environments the Lush Coastal tropical forests and the massive dry interior desert and this was probably pushed to even further extremes because there was less liquid water overall to go around on the planet because the cooling climate that had started in the late Carboniferous had now led to a full-blown Ice Age in the early Permian known as the late Paleozoic Ice Age this one spread glaciers across the southern continent of gondwana so this actually led to even more climactic extremes with so many different environments covering huge areas across this one giant land mass and this was the perfect setting for all new branches of evolution as organisms adapt to the new world around them but there was an issue up until this point everything alive on Earth was exothermic or cold-blooded meaning that they needed to warm their bodies with the heat of the sun to be able to process their food and fuel themselves fortunately if you're exothermic and you live on a world that is in the grip of an Ice Age you're probably gonna have a bad time luckily though the amniotes did have a few different strategies depending on where they were adapting to live that would give them an even further Edge on land but before we get into that let's check back in with life in the oceans with the growing glaciers at the South Pole dropping the sea level this caused the island land masses like What Would One Day become China and Southeast Asia to grow to land masses nearly the size of Australia this isolated the Paleo tetha Sea from the pantheolastic ocean even more than before and this likely led to a division in The evolutionary paths from the animals living in each and I say likely because it's hard to say 100 for sure because we don't actually have a ton of fossils from the pantheolastic ocean during this time at least of large animals almost all of what we know is from the more shallow paleo tethis and here we see that some forms of life had managed to bounce back from the devonian extinction and become abundant but some were still struggling after all this time one that still managed to hang on were the ever persistent trilobites who despite becoming exceedingly rare on a sea floor covered in mollusks economic terms and brachiopods were able to eke out a living in a handful of different species I managed to just keep chugging along but one of the most successful invertebrates from this time was a particular kind of ammonite called ghania tights now this was an older order of ammonite but it was definitely their Golden Age they're so common in early Permian Marine fossil layers the paleontologists actually used them as an index fossil to identify that they have the rock layers dated correctly and getting into the vertebrates we see that one group of fish had really moved out ahead of the others while the lobe finned and bony fish were very low in biodiversity the chondricians were taking over and diversifying especially on Clay known as Hollow cephaly which is a clay that is not very well represented today but does contain a few modern deep sea creatures like chimeras we also see some more shark-like examples of this group start to evolve known as the hybodonts but based on where the fox muscles were found it appeared that some of the species were taking refuge in freshwater environments from the true top predators of the ocean the Eugenio dantids and if you thought that armored fish sea scorpions carrot Krakens and alien sea bugs were scary meat helicoprion a shark with a buzz saw on its face this whirl of teeth was something that puzzled scientists for over a hundred years because we couldn't figure out exactly how it worked and because cartilage doesn't fossilize very well we have yet to actually find a complete skeleton of this thing so for a long time we had many wild guesses of how this jaw even worked or how it would even fit on the animal's face but in 2013 scientists were re-examining the best fossil of helicoprion ever found and after CT scanning it they settled on this as the final product of how this mess fit together it's thought that it used this tooth world as a tool to hunt the most common prey available the ghania type ammonites but at up to 8 meters long this animal was very likely the unchallenged king of the early Permian Seas as we come ashore to the site of the thriving Coastal forests things would appear to Bear a general resemblance to the jungle world of the Carboniferous but this was definitely a very different world because there was less oxygen the age of the giant arthropods was over but despite their reduced size and place on the food web they would quickly bounce back and take several new forms to fill new niches in the swampy Fern covered lands especially among the insects this is when we start to see the very first flies and beetles in the fossil record and considering that in the modern day there are currently between 350 and 400 000 different species of beetle I would say that they had figured out a set of adaptations that worked pretty well for them and one group that managed to hit their Peak during this time were the temna spondyls they took a hit at the end of the Carboniferous but in the millions of years since they had managed to make the coastal swamps in forests theirs and radiated into several new forms one of the most well known is the strange hammer-headed amphibian called diplicalis or kind of more boomerang-headed I guess we even see old Terrors like the predatory eriops managing to hang on and finally we see one branch of this group that is believed to be the earliest ancestors to Modern amphibians like frogs and salamanders a creature called CAC Ops despite all this success however the temna spondals did have an issue even though if you measure success in biodiversity they were doing quite well the fact is that they could not spread to an overwhelming majority of the land because they were still tied to the water and they would also struggle to adapt to colder regions which at first was actually something that everything on Earth was struggling with but perhaps the fact that the world was on the grip of an ice age was actually the thing that pushed some animals to to make a change that is one of the theories behind a standout feature that first evolved during this time period with some of the most famous Permian animals especially one of the top predators of the early Permian the cephenicodontid dimetrodon this was one of the various different families of synapsid who were diversifying during this time and although this species was primarily a hunter of amphibians in the swamps where it probably mostly lived it is thought that their ability to regulate their body temperature more effectively than any other group of tetrapods at the time is what gave them the edge in the wildly different climates of the late Paleozoic Ice Age we're not sure if dimetrodon sale was an adaptation for thermoregulation or maybe just used as a sexual display but what we do see is that there were several different animals especially among the early synapses acids that evolved this feature independently I mean if I'm being honest it could have been both after all we see lots of reptiles today using sales as a sexual display but we also know that the sale would have been packed with blood vessels so when blood moved through the thin membrane of the sail and the animal was sunning itself the blood would start to warm so this could have been the first steps toward the very first group of animals becoming endothermic or warm-blooded and this would be the thing that allows these animals to take over the world as well as the thing that allows me to take my next form why do you all care if my character stands upright [Music] all right now at least I don't have flounder eyes across the warmer arid regions of Pangea the diapsids and synapses were on the rise and they were starting to get larger as well this would be most evident in the first group of large herbivores to Lumber across the land the diodesids like desmotidon that have been around since the Carboniferous along with the sail-backed herbivore adaphasaurus which despite the resemblance is actually only a distant relative of dimetrodon of these groups the ones that lived in the swamps and forests were likely prey for the sail back carnivore but for the ones that expanded out into the desert they would be facing a very different threat another group of carnivorous synapsids called the dinocephalians this was one of the first groups to rise up during the beginning of the Permian and they started to diversify into many different forms there were herbivores like the dome-headed tapanosa phallus which grew to the size of a black rhino and the largest carnivore of the period titanophonius which was bigger than a tiger and had a prayer pronounced canine teeth that it would use to dispatch its prey and there were even some species of omnivores eating a mix of both plants and animals like titanosuchus there were even some that did spread into the coastal forest and become semi-aquatic returning to the water and living similarly to crocodiles and hippos in this regard and these would by far be the most bizarre like look at this thing it's called estebinosuchus and as you can see it quite literally wears the crown for the most bizarre Permian synapsid but to find a close runner-up we have to look at a different member of the synapsids from the dinosaurphalians altogether the tiny headed herbivore katiloh rikus as you can see through the Permian the synapses quickly came to dominate perhaps it was because their bodies were better suited to a wide variety of habitats during the glacial period combined with the fact that they had more versatile dental tools that made life easier no matter what they were trying to feed on but more specifically than the synapsids this was the dinocephalians time to really shine they Rose to the top and everything else was struggling to hold a place somewhere in the middle and one group that remained small was another kind of synapsid carnivore called the therapses like my new form by our masukis this animal was a dog-sized hunter who likely couldn't stand up to monsters like titanophonius or dimetrodon but it wasn't able to make a living hunting smaller prey and are a larger than average eyes means that we may have been able to make a living hunting at night when many of the larger synapsids were asleep and the same goes for fithurai sukis right Tim tip why do we keep fighting ourselves in the underdog position I mean we've definitely been in worth spots at least we have a good strategy for avoiding all the stuff that wants to kill us and plus I happen to know that better days are coming back what what was what as we come around to 273 million years ago there would then be a shift in the climate we have seen a world populated by cold-blooded animals adapt and thrive in a world in the grip of an ice age but it was gradually getting warmer again and as much as the animals did an excellent job expanding into every possible Niche over the past 25 million years now those animals were specialized to the world as it was at the time and things were not going to go as you might expect either one would think that the melting glaciers would lead to rising sea levels and in turn more water to spread rainfall to the interior of Pangea so yeah it would get hotter but at least there would be more liquid water to go around but unfortunately the way it played out was not that simple sea levels did rise but the presence of the mountains that were continuing to rise as well for the past 30 million years means that even though there was more water it was still blocked off by the mountains so it got hotter but if anything it also got even drier the only places that could get more rain were the places that really didn't need it this probably caused widespread flooding throughout the coastal swamps and forests and The Runaway effects of this would cause around 25 percent of the plant species to die out and that's never good for a food web this would once again lead to the demise of many of the animals at the top of the food chain around this time helicoprion disappears from the world's oceans as many of its different favored ammonite prey were becoming too rare for the giant to sustain itself and on land many of the temnos fondles were falling on hard times and so would many of the first synapsids that had previously been dominant and this is when dimetrodon the most famous stem mammal of all ran out of steam inland many of the groups that came to dominate did survive but so many species would be taken out that this was no longer the dinosaurphalians world and there were other synapsids that were more generalized and ready to take advantage of this new hot Earth so you're probably wondering why I chose to divide the Permian in half and if it's not already clear it will definitely become more clear in the next episode of the series basically the animals of the early and late Permian are so radically different from each other because of the extinction that took place right in the middle that it would be very hard to tell the story properly in just one episode plus this script is already over 3000 words long and I need to get started on Paleo rewind so as we go forward we will see what synapsids managed to pull through and how they will adapt to living on a continent that is continuing to slam together is the ground shaking no have a good one everybody well at long last we have come to the end of the Permian period our world has already gone through so many changes since we started with the fiery ball floating through the infant solar system despite the fact that we had just seen yet another die off of several different species leaving only around one-third of the terrestrial animals alive we would see life continue to press on and something that you may have noticed with each event that has resulted in a drop in biodiversity every time it seems like the animals that make it through are just a little bit tougher for it not necessarily stronger but better adapted to the changing world but unfortunately regardless of how enduring the plants and animals on this planet become the Earth will always have the final say in who lives or dies and as the Continental plates continue to push into each other tectonic forces were building to a Tipping Point that could have ramifications for every living being on Earth but for the moment we synapsids were still on top even though many Genera like dimetrodon and adaphasaurus were gone several others pushed on and that's where we pick up in the second half of the Permian period have a bad feeling about this picking up where things left off tectonic activity was beginning to get more volatile a string of microcontinents called chimeria sheared away from the southern gondwana in half of Pangea and started drifting north towards What Would One Day become Eurasia this caused the Paleo tetha sea to start to close and the neotethesis C on the other side does start to expand this also pushed the chain of Chinese Island continents northward on the same collision course as this happened the Continental forces that had at this point been building since the two main continents had come together at the end of the Carboniferous would result in mountain ranges and volcanoes being pushed up all throughout the massive continent despite this all being one land mass this was still made up of several continental plates all of which were pushing together which was the driving force behind all this activity one place for this would happen is at the Far Western Edge of your America pushing up mountains at the coast that in 260 million years would be known as the Guadalupe Mountains today in the 21st century this is a very small 105 kilometer or 65 mile long mountain range that is only around 2 600 meters tall at the Texas New Mexico border but during the Permian this was a substantial mountain range pushing up what was previously a part of an inland sea covered in a reef this spelled Doom for any of the marine animals that lived here at the time but this would also preserve an excellent snapshot for paleontologists to find hundreds of millions of years later in the modern day and this is just one example this would become a reoccurring theme throughout the remainder of this period the planet it's self was becoming the most violent that has been since the archaean and every time that the Earth would Roar to life the local inhabitants wouldn't stand a chance the other side effect of this was the interior of Pangea was becoming increasingly arid for all the same reasons that we mentioned in the last video when you put more Mountains out there it's going to block more rain from getting to more areas it wasn't always hot all across Pangea many areas had similar conditions to Central Asia today kind of something like the Gobi desert and also as the last of the glaciers at the poles melted away the sea levels would also continue to rise the world was definitely in crisis and as a result life was struggling to bounce back from the most recent Extinction those that were going to pull through and see either descendants inherit the world we're going to have to be the toughest that they've ever been as the continents above were experiencing such great unrest beneath the waves life was chugging along the trilobites that had been hanging on for so long had been withered down to only a couple of different families but they were about to be thrown a Lifeline in reaction to some of the creatures being wiped out in the previous Extinction the trilobites were about to explode in diversity for the first time since the solorian it finally seems like things were starting to look up the other major Niche that was left open from the mid-permian extinction was the spot as an apex predator and with the ammonites recovering and returning to their role along with the bony fish it was only a matter of time before some new sea monster came on the scene at first the lack of large macro Predators would be filled by of all things a relic family of jawless vertebrates called the conodance editors were jealous this is Rich remember when we had the flee the oceans because of all the ah that would be the disturbing set of teeth that these lamprey-like creatures had in their sucker-shaped mouths although these animals have been around since the Cambrian this time did see them expand and diversify but I still wouldn't quite call them apex predators that role would actually go to a much more familiar face with the Eugenio daunted's gone it was finally time for the hibodons to spread back into the open ocean and become top predators this is not exactly the same branch of the chondricians as modern sharks we know today but they were a close cousin and likely filled a similar role as some returned to the Open Water others remained in the freshwater rivers to dominate there and with that it's time for us to come ashore again and see what's going on throughout Pangea normally following a mass extinction we see a dramatic rise in new organisms stepping up to fill the roles that were previously held by the ones that disappeared then new plants and animals become specialized to the current environment and those would rule for as long as the new environmental conditions remained the same the problem is because of all this geologic upheaval a lot of the conditions that cause the extinction at the middle of the Permian were still continuing for several million years after and these conditions were not very hospitable for macro life in general so for about 10 million years following that event biodiversity across the globe remained fairly low but as I said in the last episode there were still some groups managing to hang on one group of plants that got their start in the early Permian and would eek Buy on the Arid Global continent would be the cycads and and this would be enough to give some animals a chance despite early cycads being nutritionally poor some herbivores were able to sustain themselves on this new type of plant these would be the synapsids and diapsids that would survive in a late Permian deserts and Coastal forests life however was a struggle and the last of the dinocephalians were still able to claim their title of dominance for the moment but their grip was slipping one species that did well for a while was Moss chops a species of tapinosphalus whose rise appears to be linked to the rise of the first cycads in response to this being the most readily food available Moss chops became well adapted for consuming tough hard to digest vegetation so kind of think of it as like the camel of its day but it would start to see some competition from equally hearty creatures like the diopside parasaur bradysaurus the parasaurs as a whole quickly spread across Pangea and became the dominant group of large herbivores eventually pushing the tapanus of phthalids to The Brick of Extinction and it's actually pretty interesting when you look at these creatures how similar these two very distinct families were I guess no matter what clade they were a part of being a squat barrel-bodied animal with a short muzzle and peg-like teeth with was the way to go in the latter half of the Permian and as these herbivores competed amongst each other of course new carnivores were going to follow suit with another dinosaurian called atenosaurus this was the monster of its time if titanophonius in the last episode was comparable to a tiger then this thing was comparable to a bear and it was the terror of any Moss chops or bradysaurus that it encountered but even though it was the king of the desert even it had some competition from other thorapsids and considering how shaky the hold these animals had on their environment was it would be all too easy for the balance of power to tip once again as we get into the late Permian around 260 million years ago we see the last of many of the previously mentioned groups finally die off the fact is that the middle Permian was just a really rough time to be alive and many of the animals were barely making it as is with such limited resources the last thing that these animals needed was new competition but new therapsids were adapting to this hellish world and if there wasn't a place for them they were going to push other creatures out of the way they took all the qualities that made the therapsids unique and built on them for instance their specialized teeth but ironically one group of herbivorous the raps that's called the disinodons traded in their teeth for a beak that made them even better at eating through tough plants and Roots than the tapiocephalids and this would be the key to their truly explosive success story they started out small with animals like robertia who still actually maintain two teeth a set of tusks theorized to be a case of sexual dimorphism since only some individuals within the same species had them and in fact some species of dysanodons wouldn't even share this Dental Arrangement at all but the fact that their teeth were becoming so varied both between different species and among the same species was a sign of things to come and as Pangea continued to dry out this would give them the edge they needed to become the dominant group of herbivores across the world this was a Showcase of how life could eventually bounce back and given enough time will manage to adapt to nearly any environment it took a while but the animals of the Permian were managing to thrive and it wasn't just the thorapsids the parasaurs were were still going strong as well but this was definitely the synapse it's time to shine besides the dysonons which exploded in diversity but remained smaller during this time we have several different animals that started to take wildly different forms one of the most noteworthy and interesting is a small creature that we call suminia this was a relative of another small borrower called venue covia who may have been getting out competed by the prairie dog lizards that were popping up all over the world so this group of synapsids went in a completely different evolutionary Direction they became arboreal trading in their more groundhog-shaped bodies for something that looks almost primate hence the name these tiny herbivores got by because they started to feed where the disinodons and parasaurs could not and they evolved surprisingly dexterous hands to help climb and manipulate their environment I wouldn't say was quite on the same level as a monkey probably more like a squirrel or a raccoon but either way very impressive for something that wouldn't even be considered a true mammal and they weren't alone in the Trees of the coastal Forest either some like the reptile solora saravis not only could climb but actually adapted the Glide from tree to tree in a similar way to the Draco lizards of today meaning that this was the first time that any known group of vertebrates evolved to take to the air in any capacity this wouldn't be powered flight like what the insects of this time could do but it was enough to avoid predators and navigate the trees and that was definitely a necessity because in place of the dinos of aliens a new group of thrapsid carnivores were going to experience the same wave of adaptive radiation as everything else living at this time the descendants of the animals like Byram so you know what that means it is time timtim [Music] to take over the world as we arrive at 252 million years ago despite all the trials our planet has put our ancestors through it seems that we were finally coming out on top life had finally bounced back on land and in fact become even more diverse and widespread than ever before the coastal forests of early ginkos cycads and conifers were teeming with life with Fish And timnus bundles still in the rivers insects and arachnids scurrying on the ground and flying in the skies and various different reptiles and synapsids both browsing on the low brush and climbing among the trees and as we leave the forest that's when things would get really impressive the daisanodons had evolved into several larger bodied forms like vivaxosaurus but another species was poised to take over the world in a way that had never been done before the beaver size listrosaurus but for the moment they still were not the top herbivores that role would still be controlled by the parasaurs with the armor-plated species scootasaurus in addition to being heavily protected from Attack these reptiles were also well adapted for the vast interior deserts of Pangea in other words they were absolutely perfect for this hostile world and with all these different animals spreading across the massive continent there was ample opportunity for new predators to go on the hunt particularly one group of carnivores who branched off from animals like by armasukas called the theriodonts this group really took off in the late Permian it seems like just about every potential prey species had some member of this group specializing to hunt them and they did this by splitting into three separate claims the small resourceful cyanodons who would feed on all sorts of small creatures like invertebrates and small reptiles in fact many of them were actually omnivorous like my new form divinia Prima which I love the name of it makes me sound like a Transformer God and some even adapted more specialized niches like hunting in rivers like Pro sinusuchus which despite having a name that suggests that some kind of crocodile-like animal I would say if anything it was more like an otter lizard and when you put it like that this is actually probably the best possible form for timtim this is great The World Is Ours it really is and I haven't even gotten into the most powerful Predators yet the next branch of the theriodons the quick and nimble therousophilians most of these Predators were medium size about like a wolf and came in a variety of different species fast enough on the ground to run down most prey and likely specialize for hunting things like listrosaurus and it should be noted that small grooves on the pronounced canine teeth and what appears to be in large glands on the skull of some species suggests that there's a possibility that some of these Hunters could have even packed a venomous bite if this is the case then this is among the earliest known terrestrial vertebrates that we have any solid evidence for being venomous and it probably would have allowed them to take down much larger prey as well as compete with the true Kings of Permian Pangea the gorgonopsids like the other two clades of this group there were several different species of gorgonopsid this clade was similar in shape to the therous of aliens except everything was turned up to 11 with these guys instead of being the size of a wolf these creatures were over 3 meters meters or 10 feet long and weighed up to 300 kilograms or 660 pounds and the pronounced canines that the cyanodons and the therous of aliens had were even more so in the gorgonopsides forming the very first saber teeth a dental Arrangement that has been so effective that it would evolve at least half a dozen more times independently in the future but these guys did it first if the cyanodons were the cunning resourceful opportunists and the therocephalians were the venomous agile assassins then these things were the ultimate stem mammal apex predators a Bruiser that was a hunter of the biggest most well-armored prey and in fact in the case of innostranciva one of the largest members of this clade was believed to actually have favored the armored scudosaurus as prey these animals struggled through the Permian arguably the most challenging period that life has endured yet and if you think about it we had been The Underdogs going all the way back to the Cambrian every time that we evolved it was in response to a new threat that was claiming dominance and by the end it seemed like even the planet was working to make things more difficult but now the monsters that we feared were defeated all because we learned to live with these conditions that nearly nothing else on Earth could and now we were never going to lose control of this planet yeah we would expand to every corner of the globe and never fall victim to the sauropsids or anything else someday we will learn to tame the very Planet itself yeah what the hell was that what the hell was what if there is one thing that has been proven Time and Time Again by our journey through the history of life it is the fact that no species lasts forever these periods of time that we talk about are human constructs to help us wrap our minds around the sheer vastness of geologic history and these expanses of time are often punctuated by something bad happening to the things that were alive at the time these are the extinction events that we normally consider that periods concluding incident the ones that leave life looking different enough on the other side that we can say that it is appropriate to label everything that follows in the geologic record belonging to an entirely different period this has happened to some extent at the conclusion of each of the episodes in this series and in fact smaller extinctions have happened intermittently throughout time that I had not even mentioned because the overall effect on the big picture of the story was relatively unaffected the point here is that Extinction is actually a natural part of life as long as the world keeps changing life will continue to change with it or fall by the wayside and in that process there will always be winners and losers with that being said however there are also some events that happened that are so overwhelmingly devastating that life very nearly didn't bounce back disasters that nearly took our planet full of life and eradicated it these are the true mass extinctions the ones where easily 70 of the species were wiped out or more and it has only gotten this bad a handful of times but but even among those mass extinctions this one is the standout this is the single most devastating event that life on Earth has ever seen so I decided that rather than cover it in one segment of the late Permian video that it needed its own chapter because over the roughly 1 million years that this event took place our world would be changed forever foreign you survived the initial blast stick with me and you may live to see the Triassic as we cover the great dying so if you couldn't tell from the last couple of episodes there was a build up to this ever since the continents had started to come together in the Carboniferous there had been a steady rise in volcanic activity this led to more mountain ranges rising up during this time than any other time previously now there are other theories about things that could have contributed to this great loss of life but there is one situation and one location that seems to be the most likely cause an alarmingly large area of Russia that today we call the Siberian traps this nearly 7 million kilometer area is marked by the presence of balsaltic rock a type of igneous rock formed from the rapid cooling of low velocity lava usually rich in magnesium and iron now this is a jarring fine not only because of the vastness of the area but also because at a glance it really shouldn't be here because Siberia doesn't sit on a tectonic plate boundary like you would expect from a location where a volcano might go off but this situation was different instead of the more common cause of volcanism especially during this time when two tectonic plates pushing into each other can cause an eruption It is believed that this was caused by a mantle plume where a massive amount of magma starts to work its way up to the surface from the mantle as this happens the above layers of crust melt and actually fuel the momentum of this event until finally it reaches the surface and well this this type of situation does not act like a normal eruption they are a slow burn that started with several eruptions throughout the area where lava spews out of the ground essentially forming an inland sea of lava at the surface and in this case about the size of Greenland this dismantle plume probably exploded continuously for about a million years with certain points of heightened activity and long periods of it just seeping lava all concluding in one final massive explosion now as if this wasn't bad enough there are also many long-term effects to consider such as the fact that as all this magma spewed up from the wound in our crust of the planet there would be a massive amount of greenhouse gases being released as a byproduct along with a chemical known as halocarbons now for those who don't know these types of chemicals are directly linked to all sorts of environmental and health issues for anything exposed to it and maybe someday I'll do a video talking about all the times that we've monkeyed around with this stuff leading to some pretty bad results besides being directly toxic to any animals it would also rapidly break down the protective ozone layer of our atmosphere and with greenhouse gases like methane getting pumped into the air and a layer that protects our planet from heating up too much from the Sun being broken down I'm sure you can see where this is going ironically despite the eruptions of the Siberian traps absolutely spelling certain death for any animals living in that region of Pangea it may not have been the blasts themselves that led to the widespread Global die-off that took place but instead a slow die off of being poisoned choked and starved as the planet first got cold as a result of the sun being blotted out by the Ash and dust only to start to warm faster than ever when the dust finally cleared and the ozone layer was no longer protecting the planet and by far the worst effects of this would be felt in the Seas where global warming would affect actively starve the oceans of oxygen as well as raise the acidity of the water our oceans had been busy with life for almost 300 million years at this point it is where our story as well as the story of everything else began and although it had had its fair share of die-offs along the way nothing has compared to this and in fact it's safe to say that nothing ever will shy of the actual death of our planet because if you looked at the ocean's 251 million years ago you would swear that's exactly what was happening many faces that had become Staples up until now some going all the way back to the Cambrian explosion were completely erased the echinoderms were almost entirely wiped out with 98 of the cranoids and 100 of the blastoids dying out bivalves lost 59 of their species which is Lucky by comparison or a testament to how Hardy the simple yet effective design of a clam is the gastropods would lose 98 percent showing how close we came to such a simple creature as a snail no longer being part of our world but if you want to consider what a very different world specifically in the oceans would have been like we also very nearly lost corals as well with 96 of the Paleozoic Coral species dying out if there or any eruptorids left by this time they were completely gone although there is some debate on whether the last of them were already gone by the end of the Permian but what we do know is that this was finally the end of the line for the trilobites a class of organisms that had endured everything that the animal kingdom as well as the planet itself could throw at them for a staggering 270 million years were done and although it's hard to pinpoint exactly how hard the cephalopods were hid because many species don't have many hard parts to fossilize to begin with there was one exception the ammonites and unfortunately the news wasn't good 97 of them would completely disappear including 100 of the gania tights that we talked about being super abundant during the devonian several groups of vertebrates were wiped out including many species of canadons bony fish and chondrick theans all in all an absolutely unfathomable 96 of the Genera that existed 252 million years ago would be gone in a million years or so that this event took place leaving the majority of the globe looking very similar to how it did in the days before the Edie Akron covered in a vast Barren ocean although the loss of life on land was not quite as all-encompassing as it was in the oceans it was still absolutely devastating there was a steep drop-off in many different kinds of gymnosperms and Seed ferns also the total Extinction of another group of plants called the gigantopterids which had previously made up the most abundant types of plants in the rainforest of the South China Islands although some smaller species may have survived this was the end of this type of forest and the collapse of the coastal Forest would result in many species disappearing the land invertebrates would not fare much better than the Marine ones with this being the single largest Extinction event that insects have ever suffered with some estimates as high as 85 percent of terrestrial arthropod Genera disappearing and since both plants and invertebrates make up the base of any terrestrial food web this was absolutely going to have a dire effect when it comes to the vertebrates amphibians like the tender spondyls were almost completely wiped out weakening their grip as the dominant Hunters at the water's edge many different groups of reptile that had been competing with the synapsids directly had been reduced in diversity or completely driven to Extinction most notably was the parareptiles like scudosaurus but as I've said before when there's a collapse of a food web it's always the animals on top that fall the hardest and this time that was the synapses many of the different species of dicinodons like bulbasaurus and diectodon would not make it out of the Permian alive and without the forests neither would sue many of or its neighbor solora saravis but one of the hardest hit groups of all would be the theriodont carnivores with all the gorgonopsids and almost all of the therousophilians dying out all in all 70 of Life on land would be taken out over the course of a million years leaving our planet a Barren lifeless husk of what it had been seemingly last week but as Bleak as this situation seemed there was still a very slight sliver of Hope life on this planet would never be the same we talk about this event being the moment when the synapses lost control of the Earth to the diapsids but the reality is nothing alive at this moment was doing well the animals that would make it through this time were the generalists who were going to have to scrape just to get what they needed to get by as the dust settled the world that would be revealed would be a truly sick Planet it was dry hot and Barren with many of the areas that had previously been able to grow for us succumbing to desertification but a few animals were hanging on for one thing the disinodons and more specifically lystrosaurus who despite seeing many of their cousins perish were about to Boom in population across the southern half of Pangea going into the early Triassic listrosaurus was the single most common species on Earth for a while 95 of the land vertebrates were these pig-sized stem mammals a bio-density that to this day cannot be rivaled by any species including humans a few therocephalians and cyanodons managed to hang on as well but the former would struggle to gain anything resembling the apex predator status they had held in the late Permian the cyanodons were likely able to hang on by staying small and not needing as much food as the gorgonopsis and therous of aliens and this would be the strategy that would carry them through the next era of Earth history in the Seas life was broken but the small four or five percent of what was left of each of the different groups would eventually start to rebuild but it would take a long time and although it's hard to see this as anything else other than dooman Gloom there was one group of animals that would eventually stand to benefit from this great dying allow me to introduce proterosaurus this is a seemingly unassuming diopside reptile not unlike many that we have already met before but this one might be different because this reptile is actually the most primitive member of a clade of reptiles called the archosaurs and with so many players being wiped off the board this would be the face of things to come this is the closest our planet has ever come to going from a gem thriving with life in our galaxy to a desolate world like Mars All In All Around 90 of the species that were alive in the Permian were gone but luckily from a small handful of hearty survivors somehow life would bounce back but it would be forever different because from here on out we're in the Mesozoic Era but today our Earth is wounded and it will take time to recover if you enjoyed this video I highly recommend watching the 10 previous episodes of this series so far I fully intend to keep going with this until I get back to the modern day and my human form and I want to thank you all for joining me on this journey have a good one everybody [Music] [Music] foreign [Music] foreign

Channel: Paleo Analysis

Views: 394,003

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Id: DbAnaeFJtV8

Length: 167min 38sec (10058 seconds)

Published: Fri May 26 2023