Marine Biologist Answers Fish Questions From Twitter | Tech Support | WIRED

I'm Professor Cory Evans I study fishes let's answer some questions from the internet this is marine biology [Music] support at gab Savage 6 asked is Finding Nemo an accurate representation of ocean life yes and no one thing that they did get right is that clownish do in fact live in enemies and they are in fact immune to the stings of the enemies one thing that is pretty different is that clown fishes actually can change their sex so in the movie Nemo's mom gets eaten and in real life after a female clownish is eaten or dies the largest male will then become the female so Marlin in Finding Nemo would have actually become a female clownish and laid his own clutch of eggs within probably the next week or two so another thing that's different is Bruce the shark so in the movie Bruce the shark is a male shark but if you look close Bruce the shark does not have claspers claspers are the male intermittent organ uh the sharks have they're own the pelvic fins they're basically two very long penises clear as dead and Bruce doesn't have them so Bruce is technically maybe a female shark and Do G's move silent as why is white sand different from brown white sand is generally derived from the shells of other animals shells get broken down either via wave action or via animal feeding and brown sand is different and that is typically uh the result of rocks that have been eroded over time most of the white sand comes from very unlikely source and that is parrot fishes they feed on Coral skeletons and when they excrete it they excrete it as this nice white fine sand so much of the white sand that you see is derived from par fish poop a single pa of fish can produce 450 kg of sand per year so that's a lot of poop that's a lot of sand at Meer win asks how do schools of fish swim in harmony so in order to answer that question we have to talk about the sensory systems of the fish so all fishes for the most part have what we call a lateral line structure which is just a long line that runs from head to tail and it's covered with what we call mechano receptors these are little hair cells that can sense changes in water pressure this is why if you ever try to catch a fish with your hand even if it's looking away from you it generally gets away from you and that's because when you put your hand in the water you push water towards these lateral line cells and the fish knows where you are without even looking typically in a fish school one fish will generally respond to the movements of the fish that's right next to it so as this fish moves it's going to push water towards the lateral line of that fish and if you repeat that over a really large scale that's how you get these really nice harmonious and synchronized movements across fish schools swimming in schools makes it easier to move through water water is what we call highly viscous so when you have something in front of you that's breaking up kind of the flow in distribution of water makes it easier for the thing behind it to swim at musoka Mike 2 ask why are orcas attacking boats the short answer is they don't want them there they're trying to move the boats out of the way and the boats generally disturb their Marine environments humans generally have a very long history of messing with whales especially from boats humans basically wiped out most of the whale populations in the Atlantic via these whaling boats the unique thing about orcas is that orcas kind of have culture like humans do they have the ability to transmit information to subsequent Generations without having to pass it on through their genes some orcas actually do have fashion there was a trend where one orca started wearing a fish as a hat and later on the other orcas in the pods also started wearing fish hats and then this fashion actually jumped to other PODS of orcas also trying on the uh fish hat craze at Red's CPS what is the fastest sea creature no Google no Google needed the fastest sea creature in the ocean is the sailfish these fish can get up to 50 m hour many of the fastest sea creatures happen to be warm-blooded what we call endothermic Tunas are famously warm-blooded these animals are also high-speed swimmers about 40 mph for a tuna at Michigan fool asked serious question where do shells come from does marine life make them and then abandon them all shells come from animals uh generally invertebrate animals that basically lay these down as protection and things like this conch shell which is actually the remnant of a very large snail Marine invertebrates over the past 300 million years have evolved the ability to take in minerals from seawater and their food Limestone or calcium carbonate and construct them into these very elaborate exoskeletons sometimes you'll find shells that have holes in the top this typically from a marine Predator like boring snails well they'll actually drill a hole into the shell of this animal and consume it some shells are really really pretty and you might be tempted to pick them up one example here is the cone snail shell but the animal that lives in these is incredibly dangerous the cone snail is actually a venomous snail we don't have antidote for their venom if they're Disturbed they will shoot a harpoon full of Venom into the pocket of the person who's likely put the shell in their pocket so uh even though they're beautiful some shell should stay at the beach at George M6 834 969 asks a starfish has no brain so how does it know it's hungry the short answer to this question is to assume a starfish is always hungry because they most likely are they are voracious Predators the starfish has no brain so doesn't have a centralized decision-making Center however each arm is packed with sensory structures and each arm will basically taste the water and once enough kind of tentacles start pointing towards where the food is the entire animal will then kind of move its body in that direction once a starfish lands on something that it wants to eat say this clan for example it will actually Force the shell of that clam open just a little bit and it'll insert its stomach into the shell of the clam so it will eject the stomach out of its own body into the shell this clam where it will then digest the clam inside its own shell and then draw the stomach back inside of them when they're done feeding at neon Gundam asks how can a Mana shrimp see more colors than I can you're telling me there's a color out there called blurple that I can't see brell greed man science and shrimp yes Mana shrimp and many other Aquatic animals have the ability to see far more colors than we can because they have more photo receptors in their eyes so mantis shrimp can see well into the UV Spectrum I'm not even sure that this is the craziest thing about mantis shrimp some mantis shrimp have the ability to punch so fast it looks like a flick when they punch that their actual punch and Club tears water molecules apart and when the water molecues rush in to fill that space that's been created it causes them to boil at really really high temperatures inside of this little bubble of boiling water the temperatures can reach and exceed the temperature of the surface of the Sun at Dynamic web page asks so freaking jealous of anglerfish times why didn't I evolve with a built-in nighttime reading lamp the short answer is because you didn't evolve in the depths of the ocean and you don't have to draw your food towards your mouth so in the anglerfish head there's a fin at the top that's been transformed into a lore and in deep sea angler fishes this lore is bioluminescent so it lights up and they use it to attract prey what this angler fish will do is it'll sit there in the middle of the water column with this light up lure in front of its face and fish will come in thinking that it's food and they will then themselves become food at w wonderbot asked what is the smartest animal in the sea it's hard to compare intelligence but I would probably argue Dolphins they have the ability to pass the mirror test which is being able to recognize themselves in the mirror other examples include octopuses some octopuses are able to solve maze problems in order to find food also fun fact many octopuses have the ability to rapidly change their color to match their surroundings at JPB low ask how do octopuses change their color their skin actually has the ability to see or perceive the color of the background that they're sitting on and that information is somehow passed on on to the chromator is that lives underneath the skin each chromator holds one pigment there might be a blue pigment a red pigment and a yellow pigment they can rapidly change the distribution of these pigments In Their Skin it allows them to rapidly change color and they have fine scale control over each of these pigment cells at Mr McKenzie sd5 asks how do you tell a fish's age so fishes generally have indeterminant growth however there is a way to tell this is a 3D printed fish skull there are a couple bones in the back of the skull here that are called ooliths they're underneath the skull but if you were to pull them out you'd find these really nice coin-shaped bones that have these concentric growth rings around them so fishes lay down these growth rings in their bone much like trees do so you can actually count the Rings in fish bone much like you would in a tree at exod Danny ask Fish Fry at my grandma's today fish with bones and fish without bones yeah this is how I classify my fish this is how I classify my fish too so it turns out you can actually classify much of vertebrate diversity into these really neat categories of fishes with bones and Fishes without bones all the vertebrate have Jaws can be broken into two distinct categories so there are cartilagenous fish which are sharks stingrays and the rare Chimera and then there are bony fishes which include trouts frogs cats dogs and you and me yes even you and me biologists typically classify humans and mammals in general as a group of organisms within the larger clay of bony fishes at cpf Channer asks do all fish have similar numbers SL types of fins and what are these fins called some of the common fins you might see are these pectoral fins off on the side pectoral in general are often used in hovering behaviors so you see these in fishes that live in coral reefs so things like rasses and Trigger fishes will often times flap their pectoral fins to hover over a structure to further investigate whatever is living in it the fins at the top are typically called Dorsal fins the front dorsal fin is particularly interesting because they often times get adapted into venomous spines sometimes even fatal in the case of the stonefish in the case of this little Nile perch it looks like one continuous dorsal fin but there's basically a skin connection between the front spiny dorsal fin rays and the back kind of feathery dosal fin Rays this back fin is called the cuddle Fin and it's used to generate thrust if a fish is trying to get away it'll beat this tail fin to help it move quickly at NIV writes asked does coral count as an animal it's so alive and so pretty it is in fact an animal and it's also alive and very pretty they're closely related to jellyfish but instead of floating in the ocean they build these complex Limestone skeletons so you can see these little holes and pock marks inside the coral skeleton and that's where the individual pops live so in life this Coral would be very very colorful however this particular skeleton is bleached so when corals get stressed because of higher temperatures in the ocean they'll expel the algae that they keep inside their tissues and they'll basically have no way to feed and they'll starve over the course of the next several weeks losing these reefs which can happen very very quickly will have catastrophic effects on tropical diversity worldwide so ways to prevent this include reducing global temperatures taking climate change seriously in general and in some very isolated cases pumping cold sea water back onto the corals at Elizabeth Rush asks how does the goblin shark even eat without its nose getting in the way goblin sharks have these very very elongate rostra or noses that they use to sense other animals in the water column in order to feed they actually have to protrude their mouth out away from their nose to catch prey and bring it back if you just try to bite something under water you'll actually push it away from you so many animals have evolved the ability to protrude their mouths and generate suction to bring prey towards them another one is the sling jaw Ras they have the ability to protrude their jaw up to a third of their total body length to bring in a evasive prey and then retract it add Jameson Rich at ask never forget that there's a creature on this Earth that was discovered and named by the people of science the vampire squid from hell so yes vampire squids are real they are a thing they were discovered in the late 1890s in the valdiva Expedition if you dropped a net thinking that there would be no life at the bottom of the ocean and you pulled up that vampire squid you would name it the vampire squid from hell too contrary to their appearance which can be quite terrifying these animals have basically made a living out of doing nothing they live in oxygen minimum zones in the ocean so they very rarely ever move and they feed primarily on leftover food that basically floats down from the surface at jaquel 882776280 are quite real sewers has been around for 13 million years and in that time they've actually evolved a broad variety of body shapes typically associated with camouflage there are things like the Leafy Sea Dragon which looks like a piece of kelp seahorses are terrible swimmers some of the worst to get around that they've evolved these prehensile tales that allow them to basically wrap their tails around structures so they can stay put the seahorse is perhaps most famous for the fact that the male seahorse gives birth the female will transfer her eggs into the brooding pouch of the male seahorse and then when the eggs hatched the male seahorse will actually give birth to the little seor babies at by Brandon white asks what is the best defense mechanism in the sea my favorite defense mechanism in the sea actually happens to be electricity you see this in torpedo rays and stargazers often times where if you grab them you'll actually be shocked the way that they are able to shock you is using these modified muscle cells that have evolved to be able to generate an electric current for some electric fishes for instance the electric eel the current can be as strong as 600 volts the electric eel can drop a horse but perhaps the weirdest defense mechanism that you'll see in the sea actually comes from hagfish slime hagfish slime feels weird it feels wet slimy but also fibrous so as you pull it apart it still has some consistency to it if a shark for instance will come and take a bite out of a hagfish before the shark can even bite down the hack fish will secrete slime and clog up the shark's mouth and gills allowing it to make an escape at MW srxo asks what do fish breathe in water or air wow how do they make bubbles down there so fish actually breathe oxygen they bring in the oxygen from the water and they extract it with their gills the these gills are really sensitive they're often one or two cell layers thick they have to remain really thin to allow for gas exchange the internal structures here that you can see in the gills are called Gill rakers they'll swim through a school of plankton with their mouths open and these rakers in the gills will trap the Plankton while allowing water to pass through one way that fishes generate bubbles through their gas splatter so some fish like the uh for instance the dojo Loach actually has the ability to release gas out of its uh anus to sink further down into the uh into the water at MJ Dua it's crazy how sea creatures just know EX exactly where to go when they migrate some marine animals will follow the magnetic field of the earth big migrations include uh the migrations that we see in humpback whales as they move from the tropics where they give birth and where they breed to temperate and colder feeding grounds where they'll feed on Plankton other big migrations include salmon they grow up in fresh water they move out to the ocean and then they can return to the stream that they were born in to reproduce and they accomplish this by following the Earth's magnetic field and also tracking the scent of the stream that they were born in at the Hindu science asked what is the Dio vertical migration and its role in carbon sequestration the DI vertical migration is the largest migration on the planet this occurs every night all around the world where Plankton will actually move up from the depths of the oceans there's mixing of the carbon dioxide in the air with the water right at the surface plant Plankton will basically extract carbon dioxide from the ocean and use this carbon to build their bodies larger Plankton will then come and eat these plant Plankton and then fishes and other animals will come eat the larger Plankton as well and then sink back down to the depths taking that carbon with them so it actually ends up being very important for the sequestration of uh carbon dioxide at C4 A1 ask you ever think about who lives in the Mar in a trench and freak yourself out yes uh the Maran trench is the deepest point in the ocean 36,000 ft deep it's deeper than Mount Everest is tall we have actually reached close to the bottom James Cameron and about six other ocean explorers have taken submersibles down into the depths of the Mariana stretch at that depth uh the ocean reaches pressures that would basically crush us instantly if we ever went down there but many animals have evolved to actually live there in order to do so vertebrates have generally reduced their bony skeletons you probably wouldn't find a Megalodon at the depths of the Mariana strench cuz Megalodon actually evolve to live in Shallow tropical waters like in the Bahamas but you might find like some weird clams at c22 honcho asks how do these bioluminescent waves work do people just throw glow sticks in there or what these bioluminescent waves are widespread around the world you can find them in places like Puerto Rico you can also find them off the coast of the Pacific Ocean they're produced by Plankton and whenever Plankton are startled or disturbed they'll released by bioluminescence to disorient Predators so they'll have little openings in their exoskeletons that allow for light to be produced at Neco BK ask y'all knew jellyfish are immortal like them don't die ever turns out some jellyfish are in fact Immortal the immortal jellyfish so apply named has the ability to revert back to its juvenile stage if it's ever injured or starving it will then later produce a genetically identical clone of itself to further perpetuate itself other animals in the ocean are famously long lived the Greenland shark is a great example these animals can reach 600 years many of our large whales can live for hundreds and hundreds of years there are still whales out there today that have the old harpoons from Harpoon ships still embedded in them some lobsters can get pretty close to being Immortal whenever a lobster grows it actually has to shed its shell they're very vulnerable during molting process because their soft parts are basically exposed and many animals are really queued in to find crustations that are molting especially once they get older it gets harder to escape that molting shell so a lobster that's been alive for you know 150 years might finally die by at BL being unable to escape that shell the estimates for lifespan are technically indefinite because if nothing eats them they can just keep going at Hannah xgirl I need to know why Evolution keeps making crabs so we don't know why things keep turning into crabs but things that are not crabs keep turning into things that look like crabs an example of an animal that is evolved into a crab is a hermit crab hermit crabs are not true crabs if you're trying to picture what a hermit crab looked like before it became a hermit crab it most likely looked quite a bit like a shrimp or a very skinny Lobster so over the course of tens millions of years these hermit crab ancestors began to roll their tails up and project them at weird angles and also enlarg their claws and eventually came to resemble the crabs that we know today at I am winter ask fishes don't have eyelids so do they ever sleep the answer to that is yes during the sleeping process in fishes part of the brain shuts off but they're still able to breathe so you can still see their Gil flaps moving they have a reduced response to stimuli so you can swim up and basically touch a sleeping fish in many cases in the case of whales uh the patterns very much the same part of the brain and tells them to go up and take a breath of air and then they'll do that and then they'll come back down all while sleeping sperm whales are really famous for this because they sleep vertically in pods you can stumble upon a pod of sleeping sperm whales and look like big tall forests in the middle of the ocean so those are all the questions for today thanks for watching marine biology support

Channel: WIRED

Views: 1,893,990

Keywords: bioluminescence, bioluminescence explained, diel vertical migration, do fish sleep, facts about fish, fish, fish 101, fish expert, fish explained, fish facts, fish questions, innovation, jellyfish, mariana trench, marine biologist, marine biology, marine biology support, marinebiology, ocean, ocean life, ocean questions, octopus, orcas, ott tech support, science & technology, seahorses, sharks, tech support, tech support marine biologist, whales, wired

Id: 2YquYkNcF7I

Length: 17min 49sec (1069 seconds)

Published: Tue Mar 26 2024