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What Was Earth Like In The Time of the Dinosaurs · Be Amazed

0:00
[SPEAKER_00]: 251 million years ago, our planet was a barren wasteland, reeling from the most destructive mass extinction that it's ever seen.
0:11
[SPEAKER_00]: Known as the great dying, this devastating event still isn't fully understood, but one thing's for sure.
0:17
[SPEAKER_00]: The Triassic period, the first of the Mesozoic era, was in full swing.
0:23
[SPEAKER_00]: Life was arduous and only the strongest would thrive.
0:27
[SPEAKER_00]: In this battle for survival, one incredible creature would come out on top, the dinosaur.
0:34
[SPEAKER_00]: But what was their world like?
0:36
[SPEAKER_00]: How did they live?
0:37
[SPEAKER_00]: And what exactly led to their demise if they even died out at all?
0:43
[SPEAKER_00]: Join me on another epic journey into the past as we discover what Earth was like during the time of the dinosaurs.
1:02
[SPEAKER_00]: After the cataclysmic Great Dying, the Earth was left an incredibly inhospitable place.
1:09
[SPEAKER_00]: In case you haven't already heard my other episode about Earth before dinosaurs, I'll just recap briefly, life was bad, real bad.
1:19
[SPEAKER_00]: But what little life was left struggled on, and 20 million years after the Great Dying, it was steadily spreading across the supercontinent Pangia.
1:29
[SPEAKER_00]: This was the Triassic Era.
1:32
[SPEAKER_00]: Because of the various empty niches left in the wake of the apocalyptic extinction event, new life developed on land sea, and even the skies to fill them.
1:42
[SPEAKER_00]: The air-ed wastelands were gradually broken up by huge conifer forests, and eventually, fern prairies.
1:50
[SPEAKER_00]: One group of land animals called the Arcasores were making a name for themselves, slowly rising to the top of the prehistoric charts.
1:59
[SPEAKER_00]: With upright limbs and a super-efficient respiratory system, they were primed for conquering the unwelcoming world they called home.
2:07
[SPEAKER_00]: But there was one specific group of archaçors destined to rise above all the rest.
2:13
[SPEAKER_00]: And he guesses, yep, dinosaurs.
2:17
[SPEAKER_00]: Though at the time, dinos were small, mostly unremarkable creatures that did little to stand out.
2:24
[SPEAKER_00]: from humble beginnings and all that A.
2:26
[SPEAKER_00]: One of the first dinos ever was the ear after.
2:29
[SPEAKER_00]: No taller than a chicken, it was once thought to be a carnivorous scavenger.
2:34
[SPEAKER_00]: but we now know it was probably a vegetarian, feasting on the new vegetation that's sprang up across the globe, but dinosaurs wouldn't stay like this for long.
2:44
[SPEAKER_00]: They quickly began to evolve, gaining more opposable arms and stronger neck bones for supporting more muscle.
2:50
[SPEAKER_00]: These adaptations would lead to bigger, more imposing beasties like the Harirosaurus stomping onto the scene.
2:57
[SPEAKER_00]: At around 10 feet in length, this was one of the largest predatory dinosaurs of the time.
3:02
[SPEAKER_00]: It boasted powerful legs and clawed four arms allowing it to keep pace and slash at its smaller prey.
3:10
[SPEAKER_00]: Like most early dinos, where exactly her aerosaurus fits in the evolutionary journey of the species remains unclear.
3:18
[SPEAKER_00]: But it's certainly set a standard for the carnivorous dinosaurs that had come to stalk the earth thereafter.
3:24
[SPEAKER_00]: herbivores would only get bigger too.
3:27
[SPEAKER_00]: Enter Plateau Saurus, the first known veggie saurus to get swall.
3:32
[SPEAKER_00]: Coming in at 26 feet long, Plateau Saurus was likely capable of rearing up on its hind legs to snag hard to reach vegetation.
3:40
[SPEAKER_00]: This would have been made even easier by its super long neck, something you may recognize from some later species.
3:48
[SPEAKER_00]: Overall, though, dinosaur life was all pretty similar at the time following a few basic blueprints, mostly bipedal, long tails, and long necks, though some longer than others.
3:59
[SPEAKER_00]: Like I said, the dinosaurs were a long way off from ruling the world.
4:03
[SPEAKER_00]: Elsewhere, there was another group of underdogs biting their time to clamber to the top.
4:08
[SPEAKER_00]: Mammals.
4:09
[SPEAKER_00]: Our own furry ancestors first appeared, the oldest seeming to be Brazil adorn, a tiny mouse like insectivore.
4:17
[SPEAKER_00]: But we'll come back to our furry family in due time.
4:20
[SPEAKER_00]: There were many more bizarre animals roaming the Triassic Wastes, one of the most notable being the longest quama, a reptile with some seriously striking appendages on its spine.
4:31
[SPEAKER_00]: Nobody really knows what they were for or even what they were made of.
4:36
[SPEAKER_00]: Some believe them to be super elongated scales, others posit it could be one of the first known appearances of feathers.
4:43
[SPEAKER_00]: Speaking of feathers, what was going on in the skies?
4:46
[SPEAKER_00]: By the end of the era there was a single species that had evolved the ability to fly, and by virtue dominated the air, the Terrasource.
4:56
[SPEAKER_00]: These reptiles boasted hollow bones filled with air, making them light enough to sustain flight, and with absolutely zero competition, the winds were theirs to conquer.
5:07
[SPEAKER_00]: One of the first terror source was Yudimor Fadon, a freaky-looking fellow with a long tail and strange tea.
5:14
[SPEAKER_00]: Seriously, its mouth was filled with all different types of nashes from sharp fangs to smaller multi-pointed teeth.
5:21
[SPEAKER_00]: Given that, and its smaller size with a 3.3-foot wingspan, paleontologists reckon it chowed down on small fish.
5:29
[SPEAKER_00]: Its large front teeth would have been perfect for snagging them, with its rear ones ideal for tearing into the fishy flesh, which reminds me primitive fish weren't the only creatures patrolling the oceans.
5:41
[SPEAKER_00]: Marine reptiles first appeared in the Triassic era, the long-necked pleasious swords and terrifying fish-like Iktaiosures being the most famous.
5:50
[SPEAKER_00]: Notably, the Triassic Iktaiosore Iktaiotiton is estimated to have reached lengths of 82 feet making it the largest known predator to ever live.
6:00
[SPEAKER_00]: You got to feel sorry for those fish.
6:02
[SPEAKER_00]: If you don't want to feel sorry for yourself, then make sure to follow my podcast.
6:06
[SPEAKER_00]: That way you'll never miss out on amazing episodes like this one.
6:10
[SPEAKER_00]: All done.
6:11
[SPEAKER_00]: Sweet.
6:12
[SPEAKER_00]: Let's march on its extinction time.
6:16
[SPEAKER_00]: These majestic creatures roam the planet for millions of years.
6:20
[SPEAKER_00]: But around 200-1 million years ago, Pangea began to split apart.
6:25
[SPEAKER_00]: And as the landmash shifted, it triggered devastating volcanic activity that would bring doom to the Triassic.
6:32
[SPEAKER_00]: 4 major volcanic eruptions occurred, dramatically cooling, and then heating the atmosphere, causing forest fires and destroying 76% of all life on Earth.
6:43
[SPEAKER_00]: Even prolific land animals like apex predator postosukus were eradicated.
6:49
[SPEAKER_00]: Dinosaurs, however, managed to survive mostly unscathed.
6:53
[SPEAKER_00]: See all that volcanism had initially thrown up huge amounts of sulfur and carbon dioxide into the atmosphere, blocking out the sun and causing an extremely cold volcanic winter which was responsible for the deaths of many species.
7:07
[SPEAKER_00]: Most dinos, however, had developed warm feathers in order to withstand the temperatures closer to the poles where more lush vegetation was.
7:14
[SPEAKER_00]: This adaptation probably saved them, and as it got warmer again, they were able to withstand the heat too.
7:21
[SPEAKER_00]: With whole swaths of competitors wiped away, the stage was finally set for them to rule.
7:26
[SPEAKER_00]: It was time for the Jurassic period to begin.
7:30
[SPEAKER_00]: As Pangea split, it formed two new continents, Loreja and Gondwana.
7:35
[SPEAKER_00]: These land masses were separated by the prehistoric body of water known as the Tethas Ocean, and by the end of the period, the Atlantic Ocean would start to form.
7:45
[SPEAKER_00]: Various seaways and islands were created too, resulting in a brand new landscape, and despite that volcanic winter, the long-term effects of the entriassic extinction had significantly heated up the planet.
7:57
[SPEAKER_00]: The now tropical seas provided the perfect home for the evolving marine reptiles, which not only survived the Triassic extinction, but capitalized on it.
8:06
[SPEAKER_00]: The Iqthia Sours were no longer as large as their Triassic ancestors, but continued to adapt, especially in the eye department.
8:14
[SPEAKER_00]: In fact, they're known for having some of the largest in the animal kingdom.
8:17
[SPEAKER_00]: In particular, the Optal Mousaurus.
8:20
[SPEAKER_00]: At almost nine inches in diameter, its eyes are the biggest of any reptile relative to its body length.
8:26
[SPEAKER_00]: around 19 feet, and would have allowed them to see prey in the darkest depths of the ocean.
8:32
[SPEAKER_00]: Meanwhile, the Policious Sores got scary, really scary.
8:37
[SPEAKER_00]: The long necktiepes from the Triassic persisted, but they diversified into playa sores, hulking carnivores with shorter necks and bigger heads, like the intimidating Lyap Luridon.
8:49
[SPEAKER_00]: But the seas were full of more than just reptiles and fish.
8:52
[SPEAKER_00]: Brace yourself because you're about to meet Dolacaris, and surprisingly, it's not an extra terrestrial being.
8:59
[SPEAKER_00]: Each your heart out of Thalmasaurus, Dolacaris's eyes were a whole quarter of its eight-inch length.
9:06
[SPEAKER_00]: Likely an ambush predator, Dolacaris would wait for unsuspecting prey to swim by, then use those grasping claws to snag them before chowing down.
9:15
[SPEAKER_00]: It may look like a crustacean, but an actual fact it was from a distantly related family, known as the Thylocosephalans, now long extinct.
9:25
[SPEAKER_00]: These Jurassic creatures shared the waters with somewhat contemporary looking fish too, and the oldest known group of living sharks, the six-gill sharks.
9:34
[SPEAKER_00]: All this new life was possible because of the warmer waters of the Jurassic.
9:38
[SPEAKER_00]: Back on dry land, the tropical climate had other dramatic effects, Laura exploded and vast forests of more modern coniferous grew.
9:47
[SPEAKER_00]: Almost all the species we have today existed by the end of the Jurassic era.
9:52
[SPEAKER_00]: The lush landscape was also home to various ferns and ginkos.
9:56
[SPEAKER_00]: They're all gymnos ferns, plants with exposed seeds that rely on the wind to spread them.
10:02
[SPEAKER_00]: And with all these new plants around, there were plenty of critters ready to chow down on them.
10:07
[SPEAKER_00]: Yes, back to the main event, the dinosaurs!
10:10
[SPEAKER_00]: Dinos of the Triassic were incredibly hard to place in terms of classification, due to how primitive they were.
10:18
[SPEAKER_00]: But by the Jurassic, these creatures had started to fit snugly into the iconic groups that would define them.
10:24
[SPEAKER_00]: For example, the less-soaked-the-saurus was one of the very first-orn at this gen's, the group that includes triceratops and stegosaurus.
10:33
[SPEAKER_00]: Lists of the source were small herbivores around three feet long and as tall as a chicken, likely living in herds to defend themselves from predators.
10:43
[SPEAKER_00]: All ornate the skins evolved up bird-like hip bone, pointing down and back instead of forward.
10:50
[SPEAKER_00]: Originally, it was thought to create more stomach space for digesting food, but these days people reckoned it might have helped with respiration, whatever the reason it was an adaptation that stuck with every future member of the order, so it must have been supremely useful.
11:07
[SPEAKER_00]: Combine this with extra specialized teeth perfect for grinding vegetation, and it's no wonder this lineage wound up so successful.
11:15
[SPEAKER_00]: On the other hand, we have the Sorrow Pots.
11:19
[SPEAKER_00]: These towering long neck behemoths made their debut in the early Jurassic, and they weren't anything to scoff at back then.
11:26
[SPEAKER_00]: But by the late Jurassic, some 160 million years ago, they were colossal.
11:35
[SPEAKER_00]: The most iconic of the time were the Brachiosaurus and the Diplodocus.
11:39
[SPEAKER_00]: Both herbivores, one was a vertical monster and the other was horizontal.
11:44
[SPEAKER_00]: Brachiosaurus used its huge 50-foot neck to reach high vegetation.
11:49
[SPEAKER_00]: But it was also crazy long coming in at 85 feet, almost as long as two semi-trailers.
11:56
[SPEAKER_00]: Even so, remarkably, Diplodocus had it beat.
12:00
[SPEAKER_00]: The longest specimen ever discovered was a gargantuan 108 feet long, half the wingspan of a Boeing 747.
12:10
[SPEAKER_00]: Comfortably, the largest land animals to ever live, Sora pods were effectively immune to predation and could keep on growing without fear, but not all herbivores were that huge.
12:23
[SPEAKER_00]: So, how did the smaller ones defend themselves?
12:26
[SPEAKER_00]: Well, if your stegosaurus used a spiky tail called a thagomizer.
12:31
[SPEAKER_00]: I know, sounds like the name of a metal band, huh?
12:35
[SPEAKER_00]: By swinging their thagamizer, Stegosaurus could give any predators a nasty momentum driven slash.
12:42
[SPEAKER_00]: And although they weren't as big as Diplodocus, they weren't exactly small either, with some growing longer than a London bus.
12:50
[SPEAKER_00]: So with big bulk and sharp tail spikes, they were certainly capable of defending themselves, even if they had brains the size of lives.
13:00
[SPEAKER_00]: As for the plates adorning its back, there are a few theories.
13:04
[SPEAKER_00]: Initially they were thought to be additional defensive tools, but these days that ideas been refuted, the plates were probably too weak.
13:13
[SPEAKER_00]: Instead, they more likely used in mating displays, or to intimidate rival Stegos.
13:19
[SPEAKER_00]: So then, what sort of predators were stalking the Jurassic Forests?
13:24
[SPEAKER_00]: One word, therapists.
13:26
[SPEAKER_00]: This class contains pretty much every carnivorous dinosaur you can think of.
13:31
[SPEAKER_00]: In the case of the Jurassic, the top dog was probably the Allosaurus, and you wouldn't want to meet it.
13:38
[SPEAKER_00]: With a jaw crammed full of serrated teeth, four arms equipped with razor sharp claws and powerful legs, this thing was built for aggressively pursuing its quarry.
13:49
[SPEAKER_00]: Think of it like a huge reptilian lion, capable of short bursts of speed, but not built for long chases.
13:56
[SPEAKER_00]: Whether or not it was a social animal like lions is up in the air, though.
14:00
[SPEAKER_00]: Some reckon they hunted in packs, working together to take down tough prey like stegosaurus.
14:07
[SPEAKER_00]: others think they were territorial loners, more likely to kill another alisaurus than kissing.
14:13
[SPEAKER_00]: The argument for the latter is convincing, after all at 15 feet tall and up to 39 feet long, that's a lot of dyno to feed.
14:21
[SPEAKER_00]: It's tough to imagine that there'd be enough grub to go around if they shared.
14:25
[SPEAKER_00]: Also, wondering the Jurassic was the Dolophosaurus, the iconic venom-spitting frilled dinosaur from the Jurassic Park movies?
14:34
[SPEAKER_00]: Only, sorry to burst any bubbles, but that's a complete fantasy.
14:38
[SPEAKER_00]: There's no evidence to suggest the dialogue had a frill, or was capable of spitting venom of any kind.
14:44
[SPEAKER_00]: Also, unlike the movie depiction, it wasn't a small predator, it was about as tall as the rock and longer than one and a half VW beetles.
14:52
[SPEAKER_00]: What an upgrade!
14:54
[SPEAKER_00]: But where did the Venom idea come from?
14:56
[SPEAKER_00]: Well, the Delafasaurus had a strange notch in its jaw, one that caused experts to initially question the strength of its bite force.
15:04
[SPEAKER_00]: If it wasn't strong enough to deal with prey itself, it must have had some alternative hunting method right, hence Venom.
15:12
[SPEAKER_00]: But without any actual evidence, it's much more likely that the Delafa Source was either a scavenger that used its sheer size to intimidate other opportunists or an expert fish hunter.
15:23
[SPEAKER_00]: That said, the jaws of Dilo have been assessed and reassessed, and scientists now think its bite was much stronger than they initially estimated.
15:31
[SPEAKER_01]: Hmm.
15:34
[SPEAKER_00]: Either way, I would not want to bump into this guy in a dark alley.
15:39
[SPEAKER_00]: Elsewhere, other therapods were making some pretty spectacular leaps straight into the skies.
15:45
[SPEAKER_00]: Enter Archaeopteryx and despite only being the size of a magpie, it left an earth-shattering impact on paleontology.
15:54
[SPEAKER_00]: At the time of its discovery in 1861, Darwin's theory of evolution had only just been written and was being hotly contested.
16:03
[SPEAKER_00]: Well, this striking dinosaur confirmed the theory?
16:07
[SPEAKER_00]: It evolved feathers and was capable of getting airborne.
16:10
[SPEAKER_00]: Though, whether that was via full flight or by gliding is unclear.
16:15
[SPEAKER_00]: Archaeopteryx represented a tangible example of evolution.
16:19
[SPEAKER_00]: Here was a theropod that had developed a specific adaptation in response to its environment.
16:25
[SPEAKER_00]: At the time of its discovery, this was groundbreaking stuff, but despite old Archaeopteryx, best efforts the Jurassic skies were still ruled by the Terrasor.
16:35
[SPEAKER_00]: Only now there were a lot more of them.
16:38
[SPEAKER_00]: The ramp for Hinkus was a small flyer with weird slanted and interlocking teeth likely used to snag fish.
16:45
[SPEAKER_00]: But just like their dyno neighbors, as the Jurassic era stomped forwards, the Terrasource got bigger too.
16:51
[SPEAKER_00]: Dear Skythanok was the biggest the Jurassic had to offer about the size of a wandering albatross, the largest flying bird today.
17:01
[SPEAKER_00]: Just like Rampie, it had some funky snaggle teeth probably used for grabbing fish and squid from the ocean.
17:07
[SPEAKER_00]: Elsewhere, another breed of tarisaur that would go on to reach even greater heights, the tarodactyls.
17:14
[SPEAKER_00]: Unlike other tarisaur's, these guys boasted a short-tail, longer handbones and very often an impressive crest for mating displays.
17:27
[SPEAKER_00]: It seems these fish eaters also boasted a throat pouch, possibly to allow excess water to drain out when plucking their prey from the sea.
17:35
[SPEAKER_00]: Terradactyl's head rather unremarkable beginning's admit, but their true potential would be realized in the next period of Earth's history.
17:43
[SPEAKER_00]: The same couldn't be said for the mammals who needed a little more time in the oven.
17:47
[SPEAKER_00]: Our ancestors diversified and thrived, evolving various new adaptations, climbing, furrowing, gliding.
17:54
[SPEAKER_00]: Many believed they were struggling to survive in a world that was dominated by dinos, but that definitely wasn't the case.
18:02
[SPEAKER_00]: Though they'd still have to wait beyond the end of the Jurassic for their true time to shine.
18:07
[SPEAKER_00]: Speaking of, you're probably expecting me to talk about some great cataclysm that rock the globe again.
18:14
[SPEAKER_00]: But, surprisingly, no.
18:16
[SPEAKER_00]: The boundary between the Jurassic and the Cretaceous isn't marked by any mass extinction event, and because of that, it's been difficult to pin down.
18:25
[SPEAKER_00]: At the time of this recording, scientists believe the Jurassic ended around 145 million years ago, but it's a pretty arbitrary distinction.
18:34
[SPEAKER_00]: Changes from one period to the next were incredibly gradual.
18:38
[SPEAKER_00]: The late Jurassic and early Cretaceous probably looked seriously similar.
18:43
[SPEAKER_00]: Though it's safe to say the Cretaceous wouldn't stay that way for long, one key development was the evolution of flowering plants and by extension bees to pollinate and help them spread.
18:54
[SPEAKER_00]: This would wind up one of the most impactful changes in the history of the planet.
18:59
[SPEAKER_00]: As the Cretaceous went on, the continents continued to shift slowly, but surely, beginning to resemble the ones we know today.
19:07
[SPEAKER_00]: These shifts hold the Earth's tectonic plates apart, creating pathways for magma to flow up from the Earth's core and creating a wild number of volcanoes and what follows volcanoes, eruptions, lots of them.
19:20
[SPEAKER_00]: All those eruptions likely led to the massive global warming that was seen in this era.
19:26
[SPEAKER_00]: Heck, the Cretaceous may have been one of the warmest periods in Earth's history, and all that rampant volcanism caused the ice caps to melt, too, leading to a dramatic rise in sea levels.
19:38
[SPEAKER_00]: In fact, sea levels during this era were the highest in the history of the planet.
19:43
[SPEAKER_00]: Naturally, with all that extra water the marine reptiles were having a field day, a new dominant species emerged, the Moseshors, predatory beasts with snake-like bodies that scoured the ocean floor for prey.
19:56
[SPEAKER_00]: Moseshors were incredibly successful, multiplying across the seas and thriving for the entire era.
20:03
[SPEAKER_00]: But none were as successful as the Moseshors.
20:06
[SPEAKER_00]: This colossal predator is thought
20:13
[SPEAKER_00]: Not that MosaSaurus was anything like giraffes, as Apex Predator of the Cretaceous Oceans they fed on basically everything.
20:21
[SPEAKER_00]: Fish, IkthiaSaurus, Pleasiusaurus, HECK, even other MosaSaurus.
20:26
[SPEAKER_00]: That is terrifying.
20:28
[SPEAKER_00]: Another less horrific Cretaceous critter was the Arkalon, the largest sea turtle to ever live.
20:35
[SPEAKER_00]: At a glance, you'd be forgiven for thinking it looks pretty similar to modern-day sea turtles until you realize that these guys reached 15 feet in length and weighed over 4,500 pounds.
20:48
[SPEAKER_00]: In the skies above the waters, the terrasource and especially the terradactals had finally hit peak performance.
20:56
[SPEAKER_00]: The iconic Terranodon's sword through the air, feasting on fish from the water beneath, with a wing span of 23 feet Terrasor's had never been so huge.
21:08
[SPEAKER_00]: But Terranodon wasn't the biggest, oh no, allow me to introduce you to Ketsu Kuitlus, possibly the largest animal to ever fly.
21:18
[SPEAKER_00]: Standing it was as tall as a giraffe, and with a 40 foot wing span?
21:24
[SPEAKER_00]: This tarot act will must have looked like a demon.
21:27
[SPEAKER_00]: It's incredible to even conceive that the beast could get airborne.
21:32
[SPEAKER_00]: It likely fed on lizards, small dinosaurs, and other tiny game which it swallowed whole.
21:38
[SPEAKER_00]: But the skies weren't the only place populated by incredible non-dinos.
21:43
[SPEAKER_00]: On dry land, the plant life remained largely the same apart from the new flowering plants.
21:49
[SPEAKER_00]: However, many animals like snakes and lizards evolved into more recognizable forms.
21:54
[SPEAKER_00]: Some of these were less cute critter and more prehistoric monster.
22:00
[SPEAKER_00]: Meet Bielza Boofo, also known as the Devil Frog.
22:04
[SPEAKER_00]: How did it get that name?
22:06
[SPEAKER_00]: No, no reason.
22:07
[SPEAKER_00]: Only that it chowed down on Flip and Dinosaurs.
22:10
[SPEAKER_00]: Baby Dinosaurs sure but still.
22:14
[SPEAKER_00]: This thing was almost definitely the largest frog of all time, coming in at almost
22:25
[SPEAKER_00]: The Devil Frog wasn't the only animal that made dinosaurs its dinner though, crocodilians and their relatives also thrived in the crotaceous.
22:33
[SPEAKER_00]: And unlike Biel's abufo, Dino's sucas dined on fully grown dinos.
22:38
[SPEAKER_00]: Possibly the largest crocodilian to ever live, this titanic gator was as tall as a grown man and 40 feet in length, maybe even longer.
22:49
[SPEAKER_00]: Yet, paleontologists reckon it could still effectively hide in bodies of water-like lakes and leap out to attack unsuspecting dinosaurs as they bent down to drink.
23:00
[SPEAKER_00]: Fossils of some of the biggest, baddest dinos of the era have been discovered bearing Dinosukus bite marks, meaning this guy had no fear at all.
23:11
[SPEAKER_00]: See the Jurassic is often thought of as the Age of Giants, and to its credit, it was the era where Dino started to get huge.
23:20
[SPEAKER_00]: But the Cretaceous is where things got kicked into overdrive.
23:24
[SPEAKER_00]: We're not entirely sure why, though it could have something to do with the composition of the atmosphere at the time.
23:30
[SPEAKER_00]: At any rate, the dinosaurs had existed largely uncontested in their niches for around 100 million years by the mid-cretaceous.
23:39
[SPEAKER_00]: This allowed them to grow and adapt without fear, further perfecting their roles, and size usually means, power, protection, and intimidation.
23:48
[SPEAKER_00]: And let me tell you, these guys were certainly intimidating.
23:52
[SPEAKER_00]: Remember those colossal sore pods from the Jurassic?
23:56
[SPEAKER_00]: Well, they were tiny children in comparison to the Titanosaurus, extra extra jumbo Sarapods.
24:03
[SPEAKER_00]: The biggest of all is likely to have been Argentina's Soros, at its biggest, it was 85 feet.
24:09
[SPEAKER_00]: Almost as long as Ireland's Heypenny Bridge, and 65 tons, as heavy as a blue whale.
24:16
[SPEAKER_00]: Like the Sarapods before, though, it was only interested in eating plant matter, utilizing that huge neck to munch from high-up places.
24:24
[SPEAKER_00]: But it wasn't just the Sorapods that grew.
24:27
[SPEAKER_00]: In the Cretaceous, the Ornithischians evolved and diversified wildly.
24:32
[SPEAKER_00]: Some became serotopsians, beaked-friiled dinos like tricerotops and styrocosaurus.
24:38
[SPEAKER_00]: These powerful creatures boasted hefty horns, making them more than capable of defending themselves from the deadliest spreads of the era.
24:46
[SPEAKER_00]: Elsewhere the patch of cephalosores appeared, by petal creatures characterized by a thick, bony skull that may have been used for self-defense or for head-butting rivals like an elk.
24:58
[SPEAKER_00]: But the most prolific were probably the hater source, or duck-build dinosaurs.
25:03
[SPEAKER_00]: Known as the sheep of the Mesozoic, herds of these herbivores were found all over the place.
25:10
[SPEAKER_00]: Unlike sheep, though, they had bills filled with hundreds of teeth, perfect for snagging vegetation and grinding it down.
25:16
[SPEAKER_00]: Some like the Parasar Alophus, boasted a magnificent hollow head crest.
25:21
[SPEAKER_00]: We're not sure what it was for, but there are a few theories.
25:24
[SPEAKER_00]: It could have been used to communicate by blowing air through it, or as a form of temperature regulation, or it might even have been a built-in snorkel.
25:33
[SPEAKER_00]: Jazzy And finally, the ankle assours hit their stride.
25:38
[SPEAKER_00]: We now know that these living tanks probably originated in the Jurassic era, but the Cretaceous is where they were most successful.
25:46
[SPEAKER_00]: The most well known is probably the Ankylosaurus.
25:50
[SPEAKER_00]: Despite being a herbivore, it was coated in bony armor and sported out thick club at the end of its tail, so this is one dyno that predatory theropods would be reluctant to mess with.
26:03
[SPEAKER_00]: That's not to say that no therapods hunted these colossal armored beasts, buckle up.
26:09
[SPEAKER_00]: The feathered dromancers stalked the land, using their oversized curved foot claws to help latch on to difficult prey.
26:19
[SPEAKER_00]: Though you might know these guys by another name, Raptors.
26:23
[SPEAKER_00]: The super intelligent pack hunters of the Jurassic Park movies made just be pure fiction, though.
26:30
[SPEAKER_00]: You see, there's limited evidence that they co-operated with each other at all, and while we believe them to have been pretty smart for a dinosaur, they weren't exactly Einstein.
26:40
[SPEAKER_00]: These prolific hunters ranged from the turkey-sized velociraptor to the massive Utah Raptor, which was as tall as a grown man.
26:49
[SPEAKER_00]: And some Dromaea-sores were probably capable of climbing trees, gliding, or even flying, so there'd be nowhere for prey to hide.
26:58
[SPEAKER_00]: Maybe the weirdest theropod of all, though, was the Uberajara, a chicken-sized freak characterized by its fur-like feathers and bizarre, keratin-shoulder spears.
27:08
[SPEAKER_00]: The spears could have been used to intimidate rivals or display for mates, but were probably not weapons, they'd be way too impractical.
27:16
[SPEAKER_00]: Besides the mini-saurus seemingly fed on insects or small lizards, so unless he wanted to skewer them and make a beetle kabob, I can't see much use for them.
27:28
[SPEAKER_00]: Now, I said maybe it was the weirdest because I still have to introduce you to a few more misfits.
27:33
[SPEAKER_00]: Like Dina Kyrus, this omnivorous weirdo was the largest of its family, the Ornitha Mimosaurs.
27:41
[SPEAKER_00]: Standing at over 15 feet tall and as long as a telephone pole, it was likely covered in feathers with a huge humpback, spoon-shaped bill, and long gangly arms ending in deadly claws.
27:54
[SPEAKER_00]: Heck, the name Dyna Chirus means terrible hand.
27:58
[SPEAKER_00]: They were seriously scary.
28:00
[SPEAKER_00]: But there was one more theropod known for its terrifying claws.
28:04
[SPEAKER_00]: There is Zeno Sora's.
28:06
[SPEAKER_00]: Like some kind of giraffe and teeter Sora's, this nearly 20 foot maverick would likely have grazed on high-up vegetation using its colossal three-foot claws to tear down branches.
28:18
[SPEAKER_00]: It probably also used them for self-defense, like a giant antider in the modern day.
28:23
[SPEAKER_00]: capable of inflicting grievous wounds when threatened, but now for the moment I'm sure you've been waiting for.
28:31
[SPEAKER_00]: Tyranosaurus Rex, the tyrant lizard king, the biggest baddest dino around, or so they say.
28:39
[SPEAKER_00]: It wasn't actually the biggest, but it was definitely bad.
28:43
[SPEAKER_00]: 40 feet long, and as tall as two men, T-Rex was an active hunter with an advanced sense of smell to hunt down prey.
28:51
[SPEAKER_00]: When it caught them, it's massive jaws were capable of biting down with more force than any other animal ever known.
28:57
[SPEAKER_00]: And yeah, it had weird tiny arms.
29:00
[SPEAKER_00]: Nobody knows for sure what they were for.
29:03
[SPEAKER_00]: Some reckon they were useful for slashing it prey while they clamped down with their mouth, others say they were for holding onto maids during, you know?
29:11
[SPEAKER_00]: But some believe they were just vestigial.
29:15
[SPEAKER_00]: A useless holdover that would have vanished entirely if they'd have continued to evolve.
29:20
[SPEAKER_00]: I mean, hey, with a mouth that big and tough, who needs arms?
29:23
[SPEAKER_00]: But if T-Rex wasn't the biggest therapist, who was?
29:28
[SPEAKER_00]: Well, that would be the Spinosaurus, but it was an altogether different beast.
29:34
[SPEAKER_00]: Spino didn't spend much of its time pursuing Saratopsians or Hadrisaurus, it was probably primarily a piss-a-vor or fish eater.
29:42
[SPEAKER_00]: Don't get me wrong, I doubt Spinosaurus would be opposed to chowing down on a conveniently placed dyno, during times of drought, it may even have been essential.
29:52
[SPEAKER_00]: But due to its dense bone structure, it would have found it relatively easy to submerge itself under water to hide.
29:59
[SPEAKER_00]: Whether it waited through lakes or swam though is up for debate.
30:02
[SPEAKER_00]: If it did swim, it's huge sail and fin-like tail probably helps for pellet through the water.
30:08
[SPEAKER_00]: However, it's also possible the sail was used for temperature regulation or attracting mates.
30:14
[SPEAKER_00]: We just don't know for sure.
30:17
[SPEAKER_00]: Mammals meanwhile evolved one key adaptation, a placenta.
30:22
[SPEAKER_00]: Used to nourish a fetus while it sits in the womb, basically all living mammals today share this trait.
30:29
[SPEAKER_00]: At this point, mammals had a lot of useful tools and all the potential in the world.
30:34
[SPEAKER_00]: All they needed was an opportunity to realize it.
30:37
[SPEAKER_00]: But that time wasn't quite yet.
30:40
[SPEAKER_00]: The Cretaceous era would come to an end, roughly 66 million years ago, with the most well-known mass extinction in history.
30:49
[SPEAKER_00]: Towards the end, volcanic eruptions became ever more common, and the outpouring lava sent heaps of CO2 into the atmosphere.
30:58
[SPEAKER_00]: Because of this, the ratio of oxygen in the atmosphere decreased, which some scientists
31:07
[SPEAKER_00]: That said, the Cretaceous Extinction is one of the most mysterious of mysteries.
31:13
[SPEAKER_00]: There are just as many that vehemently deny oxygen levels having anything to do with Dino demise.
31:19
[SPEAKER_00]: Regardless, oxygen was far from the only problem.
31:23
[SPEAKER_00]: The continents continued to shift, disrupting and destroying whole ecosystems as they did.
31:29
[SPEAKER_00]: Then just when things seemed like they couldn't get any worse, a Bolivian arrived from above.
31:35
[SPEAKER_00]: A colossal asteroid over six miles wide collided into the Earth, creating a crater 111 miles wide.
31:45
[SPEAKER_00]: Shock waves were sent around the globe causing wildfires, earthquakes, tsunamis and all manner of catastrophic natural disasters.
31:54
[SPEAKER_00]: Unimaginable amounts of ash filled the atmosphere, blocking out the sun for months on end.
32:00
[SPEAKER_00]: in such diabolical conditions up to 60% of plant-life died, and every large animal was eradicated.
32:08
[SPEAKER_00]: Tiny creatures like mammals, lizards, snakes, and fish survive, likely by hiding away underground or deep underwater, but big marine reptiles like the pleziosaurs were destroyed, and tarosaurs were snuffed out entirely.
32:22
[SPEAKER_00]: And of course, most dinosaurs went extinct, too.
32:26
[SPEAKER_00]: Wait, what?
32:27
[SPEAKER_00]: Most?
32:28
[SPEAKER_00]: Don't you mean all of them?
32:31
[SPEAKER_00]: Well, no.
32:31
[SPEAKER_00]: The dinosaurs survived the extinction, at least one type did, the tiny feathered therapists.
32:39
[SPEAKER_00]: Their size again allowed them to escape the harsh conditions and right out the cataclysm.
32:45
[SPEAKER_00]: But what happened to them?
32:47
[SPEAKER_00]: Well, they evolved into birds.
32:50
[SPEAKER_00]: That's right, dinosaurs eventually became the pigeons you see pooping on the sidewalk outside the Kabab shop, how the mighty have fallen.
33:00
[SPEAKER_00]: In the aftermath of the apocalypse, the tiny animals that survived emerged from burrows to a dead world.
33:07
[SPEAKER_00]: The Mesozoic, the age of reptiles, was over.
33:12
[SPEAKER_00]: Finally, it was the mammals turned to rule the Earth, but that's another story.
33:17
[SPEAKER_00]: If you're hungry for more, remember to check out my episode, this is what Earth was like before dinosaurs.
33:24
[SPEAKER_00]: It's a classic if I do say so myself.
33:28
[SPEAKER_00]: Thanks so much for listening, and I'll catch you in the next episode.