What Was the Earth Like When Dinosaurs Were Around?

approximately 252 million years ago the earth's biosphere suffered from a tremendous blow almost 96 of marine fauna around 70 percent of land vertebrates and roughly 83 percent of insects perished within a period really short by geological standards the causes of this disaster are still obscure but whatever it was the dreadful calamity didn't wipe life off the face of the earth quite on the contrary it proved to be a milestone that marked the beginning of a new era this is when there emerged the most well-known prehistoric creatures dinosaurs cosmo the first in outer space the permian triassic extinction event marked the beginning of the mesozoic a new era in the geologic history of the earth it began approximately 252 million years ago and continued for around 186 million years this was a time when our planet was actively transforming and gradually assuming it's today's looks the most crucial tectonic process of the epoch was the splitting of the single supercontinent pangaea first it broke down into two landmasses lorasia and gondwana which in their turn went on to form the continents we know today with several large mutually independent territories separated by seas and straits the conditions were perfect for independent ecosystems to emerge which gave impetus to new evolutionary adaptations in terms of climate the mesozoic was the warmest era in the entire history of multicellular life forms throughout this era there was no ice shield even of the pearls that would cover the ground for a long term still temperature would drop from time to time which forced both flora and fauna to adapt to the newly imposed conditions the mesozoic comprises three periods and the first one is known as the triassic it began around 252 million years ago and continued for around 51 million years this was the time when tectonic processes in the earth's interior were just starting to break pangaea into separate continents and the supercontinent remained whole for most of the period the ural ridge one of the oldest mountain ridges existing to this day completed its formation in the triassic at the time the mountains were in their solid days and comparatively high the period's climate was relatively dry and hot which is why there were lots of deserts at the time and the area of inland bodies of water diminished there was 10 to 15 percent of oxygen in the air for most of the triassic and then around 215 million years ago its level gave a sudden leap to reach as much as 19 percent the reasons for this phenomenon haven't been established for certain but it is assumed that it may have had something to do with the evolution and spreading of certain varieties of marine or land plants prehistoric seed ferns accounted for the overwhelming majority of the flora of the day but later on they were gradually ousted by more progressive groups of plants those included psyches ginkgo and prehistoric conifers many of these orders have survived our day although now they're not as diverse as they used to be marine life meanwhile was following its own course of evolution the oceans emptied by the perm triassic extinction were gradually populated by turtles and teleasts and the first ichthyosaurus held the niche of large predators later on they were to become reptiles best adapted to aquatic environment but in the triassic these creatures were still rather primitive an example of these is symbol spondulis which lived 240 to 210 million years ago this giant seasaurian measured 6 to 10 meters in length and date mostly fish this impressive creature had a long thin body half of which was a flexible tail its head was rather large and the elongated sharp muzzle boasted a nice set of small and sharp teeth symbol spondulis's limbs looked like diving fins but it appears they were used only to stabilize body position in water the thorian skeleton structure suggests that it traveled through water by making wave-like movements and generally speaking was rather clumsy the most common representatives of landfauna of that time were raqqa soria prehistoric ancestors of dinosaurs crocodile amorphous and birds as well as other animal species by the middle of the period first dinosaurs evolved from ancient arcasauria as independent species but there was still a long and hard struggle for survival up ahead for them it was only by the end of the triassic that dinosaurs started to establish their dominance in the earth's biosphere after sharply growing in size which incidentally coincided with an increase of oxygen in the atmosphere with dozens of films and thousands of books about horrifying saurians anyone today would be familiar with what they looked like at the same time these giants seem to eclipse other species which are by no means less important and interesting for example oligocythus a small creature that lived in the late triassic around 200 million years ago this small and deft little animal was a genus of cyanodance prehistoric animals that differed from mammals in some not very clearly noticeable traits oligocyphus had a thin flexible body measuring around 50 centimeters it grew fur and generally looked like a weasel warm blooded and herbivorous it was widespread on the territories of today's north america europe and china even though it isn't known whether oligocyphus had a pouch on its stomach the structure of its skeleton allows us to assume that its babies were quite small which is typical of today's marsupials it is also highly likely that oligocyphus fed its babies on milk another assumption about these creatures is that they dug boroughs and made homes there they also took great care about their babies which may be evidence of a comparatively high intellect unfortunately these creatures perished at the beginning of the jurassic period supposedly due to lack of food and heightened competition still they remain the oldest prehistoric animals that look like today's mammals most the triassic jurassic mass extinction heralded the end of the triassic period a great number of amphibians some arcusauria other reptiles as well as many plant orders vanished from the face of the earth among the possible reasons for this disaster of volcanic activity a change in the global ocean level and sudden climate change either way the extinction event vocated a number of ecological niches which allowed dinosaurs to establish a firmer position on the evolutionary arena of the earth the next period of the mesozoic was the jurassic it began about 201 million years ago and ended about 145 million years ago which makes it roughly 56 million years long this was a time of large-scale tectonic movements and reformations it is in the jurassic that the supercontinent pangaea finally split to form several land masses mutually separated by shallow seas if we look at the map of the earth at the end of the jurassic period we'll be able to distinguish the shapes of some of today's continents although they would be positioned in unexpected places since the new continents were mutually independent their emerged isolated biosystems that is why some animals and plants that were abundant on one continent would be non-existent on another the earth's climate was warm and humid for most of the jurassic period and by its end a comparatively short cooling occurred great areas on land were covered with tropical forests which were for the most part cycas gymnosperms to tresembled palm trees conifers were also widespread their looks were reminiscent of today's cypress trees and pine trees on land meanwhile there started the epoch when dinosaurs positively flourished their diversity was rich and they held most ecological niches while dominating almost every single one of them among these creatures one could come across both small saurians the size of a cat and real giants herbivorous dinosaurs known as sauropoda came to be widespread in the jurassic with some typical representatives like brachiosaurus brontosaurus diplodocus and others they resembled each other very much the largest one titanosaurus measured as much as 25 to 30 meters in length and could weigh over 75 tons an unusual feature typical of sauropoda is the so-called sacral brain a widening in the hind part of the vertebrae that hypothetically could contain 20 times more nervous tissue than cranial brain today it is posited that the sacral cavity was likely to be filled with a glycogen body which was a source of additional nutrition for the giant saurian's nervous system alongside dinosaurs other animal species were evolving as well such as mammals reptiles and arthropods the oceans were richly populated with bivalve mollusks which in many ways resembled their today's descendants the apex predators in the marine food chain were various saurians like ichthyosaurus and pliosaurus looking at a thalmasaurus which lived at the beginning and the end of the jurassic period and comparing it with symbol spondulis which lived earlier it may be hard to believe that these animals are in fact related ancestor symbol spondulous lived 240 to 210 million years ago length 6 to 10 meters elongated body and head badly adapted to aquatic environment descendant of thalmasaurus lived 160 to 145 million years ago length up to 6 meters streamlined body vertical tail well adapted to aquatic environment this marine saurian had a dolphin-like body with an elegant and powerful crescent-shaped vertical tail it is thought that the animal breathed atmospheric air and was able to stay around 20 minutes under water develop speeds of over seven kilometers per hour and dive as deep as 600 meters judging by ophthalmosol's teeth structure its diet consisted for the main part of mollusks including squid the animal's eyes were another distinctive feature in its appearance their diameter measured around 10 centimeters and they were protected by a bony sclerotic ring it is thought that a thalmosaurus could see well in the dark which was a valuable asset for deep water hunt and so the animal was free to dive far down where larger saurian predators couldn't get the last period of the mesozoic era is called the cretaceous it began 145 million years ago and lasted for around 79 million years which makes it the longest one in the mesozoic the continents continued to break apart throughout the entire cretaceous india detached itself from africa and slowly drifted in the direction of asia across the indian ocean south america broke away as well and made its way westwards eventually by the end of the period africa australia greenland north and south america assumed shapes close to those of today while europe and asia were starting to get clearly defined borders the climate in the cretaceous was comparatively cool in the period from 100 to 85 million years ago the average temperature increased somewhat and then cooling continued which persisted till the very end of the era this is exactly when tyrannosaurus and triceratops were around the most widely known dinosaurs and truly distinctive symbols of the mesozoic still the period is much more notable for the spread of flowering plants first trees and then grasses they formed turf and so strengthened the soils and made them more fertile while nutritious seeds served as food for a wide variety of species this gave evolutionary impetus to diversification of mammal species and also for some herbivorous dinosaurs but on a smaller scale even though reptiles were dominating in all the ecological niches of that time mammals continued to evolve they grew to be more and more diverse and by the end of the period it was possible to single out separate groups like congolets yolypo typhla predators and primates reponomas which lived around 125 million years ago was one of the largest mammals of the cretaceous its body measured up to one meter in length and it weighed 12 to 14 kilograms this creature's appearance may have been similar to today's tasmanian devils its teeth structure suggests that it was a predator but its limbs were short and clumsy so probably this animal was a scavenger incidentally an interesting find was an earth to archaeological diggings it was reponomous's skeleton with bits of a small dinosaur in its abdominal area this may serve as evidence that some mammals of the time could hunt small dinosaur species like cetacosaurus and dakyon authorities meanwhile large aquatic saurians had long been dominating the seas ichthyosaurus plesiosaurus and mosasaurus however around 1995 million years ago their population sharply dropped after the extinction event brought about by the second oceanic anoxic event which had to do with a sharp decrease of oxygen in the ocean one of the suggested possible reasons is increased underwater volcanic activity the end of the cretaceous was probably the coldest time in the mesozoic all living creatures set about adapting to the inexorably dropping temperatures and dinosaurs were no exception around 70 million years ago the territory of today's northern alaska above the arctic circle was inhabited by peculiar dinosaur species this sauron is known as nanuxorus remotely related to the horrifying giant tyrannosaurus rex this dinosaur admittedly resembled it but its size was smaller the body of nanuksaurus measured around six meters and it weighed just around a thousand kilos that is approximately eight nine times less than tyrannosaurus rex this shrinking is thought to have had to do with a lack of available food in its habitats forced to survive in the dire conditions of the far north among snowy stretches and in the semi darkness of the polar night this dinosaur developed some unusual features first of all it is likely that it was warm blooded and incidentally the metabolic processes in its body ran their course remarkably fast for example as is the case with today's birds secondly nanuksaurus's body was covered with several layers of down and feathers which allowed it to preserve warmth in the severe northern climate this suggests that the northern saurian was probably an active and fast-moving predator but in the conditions of the polar knight traditional ways of hunting prey are not that effective that is why it appears that nanuksaurus had an exceptionally well developed sense of smell and sensitive night vision these assumptions are confirmed by the build of its cranium summer in northern latitudes was short and rather cool so additional sources of warmth were needed for dinosaur eggs so that the babies developed well nanuksaurus is thought to hatch its eggs and to take great care about the young ones studies of fossil finds show that the volume of the brain of this species was rather big potentially this dinosaur was as intelligent as most of today's birds unfortunately these evolutionary adaptations didn't save nanuksaurus from extinction around 66 million years ago the cretaceous paleogene extinction event caused all non-avian dinosaurs to vanish off the face of the earth alongside marine saurians pterosaurs and many other species still the terrifying saurians left their imprint in the history of our planet and the ecological niches vacated by them were promptly occupied by birds and mammals this marked the beginning of the cenozoic era its highest being was the unique creature that came to be known as homo sapiens the self-proclaimed king above all nature its evolution has only just started and time will show what it has in store for this species dear friends if you have anything to say about all this feel free to do so in the comments below your support means a world to us because videos of this series take a lot of time and effort to create please subscribe to be in touch with cosmo and we'll be happy if you give us a like this will inspire us to produce and post a new video faster let's keep in touch you

Channel: Kosmo

Views: 3,641,797

Keywords: earth, dinosaurs, extinctions, earth with dinosaurs, continents, prehistoric earth, who lived alongside dinosaurs, what earth used to be like, global extinctions, first dinosaurs, end of the world, mesozoic, pangaia, gondwana, life, ice age, feathered dinosaurs, archeosaurs, dinosaur rex, largest dinosaurs, aquatic dinosaurs, cataclysms, dinosaurs died, global cooling, how dinosaurs appeared, what life was like millions of years ago, planet, science, cosmo, kosmo

Id: n_teJd4-GGw

Length: 19min 3sec (1143 seconds)

Published: Sat Jan 22 2022