All posts by Nightmare 3000

Time: 70 Million Years Ago

Location: Mongolia

Sunset over Mongolia, believe it or not, this area will one day become the Gobi Desert. Contrary to popular belief, this area was not the arid, semi desert that is commonly depicted in media, instead it was a huge swamp forest. And in this swamp lurk some of the most fascinating dinosaurs of all time.

A huge clawed hand plunges into the swamp water and pulls out a bunch of water plants, before shoving them all into a huge beaked mouth. This weird animal is a Deinocheirus, and there is a story behind that is as strange as it is. When it was first discovered, the only remains of Deinocheirus were of its massive arms, which, at 7 feet long, were the largest of any known dinosaur, and for years, it was portrayed as a massive relative of carnivores such as Giganotosaurus.

Until recently in 2019, where more remains were found, and these new remains revealed a very strange creature. Deinocheirus was not a large carnosaur as previously believed, but was actually an oversized ornithomimid, more closely related to struthiomimus than to Spinosaurus. What was once thought to be a huge mouth filled with sharp teeth became a long bill with no teeth, reminiscent of today’s spoonbills, those massive hands that made it so famous were not used for slaughtering prey, but were rather used for scooping up water plants from the riverbed. Perhaps the strangest discovery was the addition of a hump on the animals back, supported by bone struts similar to those of Spinosaurs, this hump likely stored fat for when times got tough.

And times certainly will get tough in a few months. It is the end of fall, and what lies ahead are 3 months of freezing temperatures and scarce food.

In the meantime however, this Deinocheirus is simply content with munching on swamp plants.

Nearby, however, more immediate trouble is brewing. These hadrosaurs are Saurolophus, named for the crests on their heads. They use these to communicate, making trumpet-like sounds to call to each other. Suddenly, one of them makes a loud blaring call, an alarm signal. The reason for the call is revealed when he bursts through the trees. Tarbosaurus, a cousin of Tyrannosaurus, and the top predator of this region.

He charges at the herd, aiming for the lead female. He catches up to the herbivore and bites her on the tail, but before he can tighten his grip, the hadrosaur wrenches her tail out of his grip before turning around to face her attacker, rearing onto her hind limbs. She kicks at him furiously with her hooves, landing a few blows before going back on all fours. The carnivore shakes off the hits and lunges again, but the herbivore aggressively rams her attacker and shoves him over, knocking the Tarbosaurus to the ground. Seeing her chance, the Saurolophus guns it, sprinting away as fast as her legs will carry her as the Tarbosaurus struggles back to his feet.

Haven’t done one of these in a while, so I thought I’d bring the previews back.

Last Time on Walking With Dinosaurs: We saw ice giants duke it out on the tundra, now we will watch the top predator of the Cretaceous traverse the deadliest oceans of all time.

Chapter 10: Seven Deadly Seas

Time: 73 Million Years Ago

Location: Kansas

Sunrise over a late Cretaceous beach, a giant turtle slowly lugs its body back to the water. This giant reptile is an Archelon, with a shell 16 feet across and weighing almost a ton, it is the largest sea turtle of all time. But like its modern relatives, it is as graceful as a sea lion under the waves, it’s long front flippers providing propulsion while the smaller rear ones steer the animal through the water. But also like it’s relatives, it is slow, cumbersome, and clumsy on land. Just like modern turtles, it hauls itself onto shore at night in order to lay its eggs, the whole ordeal is very exhausting for the mother turtles, and they will often rest at the surface afterwards. Unlike most turtles, Archelon’s shell was not a solid piece, instead it was a series a rib like struts, covered in tough, leathery skin, more similar to that of the aptly named leatherback sea turtle. But as she rests on the surface, the turtle leaves herself open to attack from below, and in these calm waters lurk the deadliest killers of all time.

As the Archelon goes back under, her vision is suddenly filled with a long, narrow snout bristling with teeth. Before she can even react, the mosasaur slams its mouth shut, crushing the Archelon’s head instantly. This is a Tylosaurus, one of— no, the most dangerous creature in these oceans. Reaching up to 50 feet long, weighing almost 8 tons, and with a bite force twice that of a saltwater crocodile, it sits at the very top of the food chain. The only thing an adult Tylosaurus has to fear is another Tylosaurus. But even these guys have soft sides, this one for example is a mother. Unlike most of their relatives, the monitor lizards and snakes, they do not lay eggs, but rather give birth to live young.

Mosasaurs have a similar spawning method to modern whales, they only give birth to a single giant baby. Like whales, mosasaurs also have a strong maternal instinct, the youngster stays with its mother for almost 10 years before it goes off on its own. This calf is only around 9 months old, but he is already 18 feet long and weighs as much as a truck.

As the mother digs into the archelon, she deliberately makes sure to fling away a few chunks, giving the calf something to eat as well. Soon the duo are off, similar to great white sharks, mosasaurs migrate to follow their prey, and around this time of year, small plesiosaurs called dolichorynchops are making their way to their breeding grounds, lagoons on the eastern side of the Western Interior Sea, the shallow waters are perfect for raising their young. And in order to stay fed, the tylosaurs have to follow their prey every step of the way. But it’s a treacherous journey, even for tylosaurs, while the mother herself doesn’t have much to worry about, various animals would love a bite of tylosaurus calf, giant relatives of today’s great white called Cretoxyrhina stalk the oceans, snapping up any small morsel they can find, Portheus, also known as Xiphactinus, a monstrous relative of today’s herrings, viciously choke down anything that fits in their mouths. Even other tylosaurus regularly kill juveniles of their own kind.

9 Hours Later

As midnight hits, the tylosaurus duo sleep at the surface, like modern whales, mosasaurs have lost the ability to breathe automatically and have to consciously control their breathing, meaning that they can only shut down one half of their brains at a time when they’re asleep, or end up suffocating to death. But by doing so, they are missing out on a gorgeous light show.

Below the sleeping giants, the ocean is lit up by thousands of bluish-purple lights. These are ammonites, a type of shell bearing cephalopod. The bright lights they produce are caused by special chemicals in the skin of these animals, when they interact with each other, they produce light. This ability allows them to attract mates, but also has the unfortunate side effect of giving away their position to predators. Predators like this Ptychotus, and this unique shark has a way of getting around the Ammonite’s shell.

Teeth, hundreds of them, and these aren’t your usual pointy shark teeth, Ptychodus’ teeth are shaped like small rocks with ripples on them. These teeth aren’t designed to cut and slice, they are designed to crush and smash.

The Ammonites know their easy to see however, and they have measures to protect themselves. They can control their bioluminescence to send signals to others, and thus can signal the approach of danger. The Ptychodus charges into the ammonite school, but suddenly the entire school stops glowing.

It’s a chain reaction, when one ammonite shuts off its lights, the one next to it shuts off its lights, and so on until the entire school has blacked out, making them much harder to see and harder to attack. For a few minutes, the Ptychodus circles, searching for a target to engage, but the pitch black of the ocean makes it impossible.

However, the shark has a way to counteract this, a special organ called Ampullae of Lorenzini form tiny dots on the shark’s face, these organs can sense the electric currents produced by living creatures. Including ammonites.

The Ptychodus suddenly lunges, and there is a cracking sound as he digs into his meal

9 Hours Later

As the sun rises, the tylosaurus stir. Daylight means breakfast time, and like all hunters, Tylosaurus are equipped with the tools to find said breakfast.

The mother tylosaurus sticks out her long, forked tongue, tasting the water before bringing it back into her mouth. Like modern snakes and monitor lizards, mosasaurs have forked tongues, and this allows them to smell in stereo. When they stick the tongue into the water, smell particles get stuck to it before getting transferred to the Jacobson’s Organ at the roof of the mouth, just like that of a snake. And depending on which side of the tongue picked up more particles —ergo, a stronger smell— the tylosaurus can determine whether the smell came from the left, the right or directly in front. It’s a powerful sense, and Tylosaurus can detect a drop of blood in 10,000 gallons of water.

Soon enough, the mother has picked up a scent, and she begins following it.

———

The source of the smell is a pod of dolichorynchops, small agile plesiosaurs. These little guys are relatives of the liopleurodon and plesiopleurodon of old, but their glory days as top predators are long gone. There is a new ruler of the sea now, and the pod are currently being stalked by her.

The Tylosaurus has already set up the ambush, placing herself in an L shape against the seabed, she gives herself maximum leverage for a high speed ambush, she just needs to wait until one of the plesiosaurs is in the perfect position.

Suddenly, she lunges, rocketing towards the surface at nearly 50 miles per hour. For the unfortunate dolichorynchops, it’s like getting hit by a freight train. Grabbing the plesiosaur in her jaws, the momentum of the Tylosaurus’ charge carries her clear out of the water and nearly 20 feet into the air. Once she splashes back down, she swallows her prey whole, just like a snake.

Such a large meal will keep her going for weeks.

The youngster also tries his hand at attacking the group, swimming after a younger dolichorynchops before biting it on the fin. The plesiosaur spins round before swimming the other way, making the calf’s grip slip off. But it isn’t over, the young Tylosaurus continues to give chase, but something else snaps up the dolichorynchops.

It’s another Tylosaurus, a big bull, and they do not like kids. At all. The young Tylosaurus turns tail and swims away, but the older bull notices and gives chase. Thanks to being smaller, the calf has speed and agility on his side, then suddenly another Tylosaurus rams the bull. It’s the mother, and she doesn’t take too kindly to her child being threatened. After recovering from the hit, the two carnivores circle each other.

Like other mosasaurs, Tylosaurus are extremely territorial, and both Tylosaurus bear a multitude of scars from previous battles, showing that they know their way around a fight, it’s just a matter of who chickens out first. If neither of them do, then the ensuing fight could be fatal.

The two continue to circle each other, sizing each other up. The mother is a good 45 feet long, but the bull is almost 5 feet longer, and a good deal heavier as well. However, our female refuses to back down, she has a youngster to protect, and and only death will stop her from doing so. After a few more seconds of circling, the male swims alongside the female and the two start biting at each other, each trying to get ahold of the other’s snout. The female backs away before ramming the male hard in the side, sending out a spray of bubbles as the air is forced from his lungs. The two back away before slamming into each other, both trying to force the other one aside. Suddenly, the female grabs the male’s snout in her jaws, clamping down hard on her rival’s head, she twists upwards, snapping his neck instantly and leaving his body to slowly sink to the ocean floor.

5 hours later

The Tylosaurus duo have finally reached their destination, a small bay on the west side of the sea, here they will set up shop until their true reason for traveling arrives. Until then, it’s time to have some fun.

The calf nips at his mother’s flipper, and almost immediately, she snaps right back, causing the calf to swim away, while the mother playfully gives chase.

That Night

As the sun sets, a shoal of Gillicus move in from the open sea to spawn. Gillicus are relatively small, only about 6 feet long, so it wouldn’t be a fitting meal for the Tylosaurus, but its presence brings in something that the Tylosaurus are after.

A series of huge fish shoots up from the depths. These are Xiphactinus, 19 foot long giants that feed primarily on smaller fish, and these are what the Tylosaurus are after. In seconds, the mother Tylosaurus grabs one of the giant fish before biting down with all of her strength, the sheer power of her bite splitting the Xiphactinus in half. As she swallows it down, the calf grabs the discarded half, swallowing it down as well. Without missing a beat, the mother goes for another one, grabbing it by the tail.

The calf now gets in on the action, instead going after some of the Gillicus, swallowing them whole. The assault continues for almost ten minutes, both mother and son eating until their stomachs bulge, and when they’re done, they swim away, ready to sleep off their large meal.

Next Time on Walking with Dinosaurs: We explore prehistoric Mongolia, exploring the story behind the Giant Claws.

Last Time of Walking with Dinosaurs: We took a journey with the killers of Africa, watching how they lived in the lush swamp forests. Today we will solve the case behind this floating raft of carcasses in an Arctic river.

Chapter 9: Ice Giants of Canada

Time: 75 Million Years Ago, Late Cretaceous

Location: Northern Alberta, Canada

An early spring day on the tundra of Late Cretaceous Canada. Spring time is normally a time of rejoice for the creatures of the Arctic, with the sun signaling the end of the polar night. But this year, the air is ripe with the smell of rot. And the local river is the reason why.

The water is virtually clogged with a putrid blob of rotting carcasses, blood and sludge seep into the water, providing a feast for the fish below. This raft of decaying flesh and bone used to be one of the most spectacular sights in this part of the continent, a massive herd of Centrosaurus, now reduced to a smelly feeding platform for some scavenging pterosaurs. But what force on earth could completely demolish an entire herd of these heavily armed, 3-ton ceratopsids? To answer that, we need to travel to a few weeks before now.

4 Weeks Ago, Montana

This forest is where our story begins, it is the end of winter, and that means that animals that migrated south last year are migrating back north to their summer feeding grounds. And this herd of Centrosaurus are leading the charge northwards, usually, Centrosaurus herds only comprise of 30 or so individuals, but during mass migrations like these, they can join together in massive super herds up to 500 strong, with over 1,500 tons of animal on the move, it is the largest annual migration on Earth.

However, as always in the natural world, wherever there are herbivores, carnivores are never far away. This is a pack of Gorgosaurus, and these guys are relatives of the famous Tyrannosaurus rex.

Tyrannosaurs have their roots in the Jurassic period, as a group of small, raptor like hunters called Tyrannosauroids, throughout the Early Cretaceous, a group known as the Eutyrannosaurs branched off from this group. And from this, another group, the Tyrannosaurids branched off and then split, forming two families. The larger, bulkier Tyrannosaurinae, which includes Tarbosaurus and of course Tyrannosaurus, and the smaller, leaner Albertosaurinae, which is the family that Gorgosaurus belongs to.

For the Gorgosaurus, spring is also a time for migration. For them, Centrosaurus are food, and as the herbivores move out, the carnivores have to follow them, or else risk starvation.

1 Week Later

As the Centrosaurus herd head northward, it doesn’t take long for them to be joined by other dinosaurs.

This is a herd of Parasaurolophus, 40 feet long and nearly 7 tons, they are massive animals, dwarfing the Centrosaurus. Parasaurolophus are part of a relatively new family of dinosaurs, the hadrosaurs. Descended from relatives of Iguanodon, these dinosaurs possess a sharp, horny beak that they use to shear leaves off plants, and after that, rows of chewing teeth crush the plants into a pastes that they swallow. This makes them easier to digest and extract energy from, allowing hadrosaurs like Parasaurolophus to spend less time eating and sleeping than other herbivores.

Just like the Centrosaurus, they too are migrating northwards for the spring thaw, where they’ll catch the first shoots of grass as they bloom.

Like always though, the carnivores are never far behind. The Gorgosaurus have used their sense of smell to track down the herds. They came for the Centrosaurus, but the Parasaurolophus’ lack of armor and horns makes them a more appealing target for the carnivores.

Unlike their larger relatives, Gorgosaurus do not stalk their prey. Instead, they use their longer legs to run down their prey, exhausting it until it cannot fight back or run anymore.

The carnivores charge, hissing and bellowing to alert the herd to their presence. They want them to run. And run they do, the Centrosaurus lead the charge, and soon enough the Parasaurolophus run as well, raising onto their hind limbs to run faster. The Gorgosaurus’ plan is working so far, in their panic, the herd is scattering exposing the weaker animals, one of the Parasaurolophus is being slowed down by a bum leg, and quickly gets outrun by the rest of the herd. Left behind, she is seemingly an easy target.

But something becomes very apparent as the Gorgosaurus surround her, Parasaurolophus are quite a bit bigger than Gorgosaurus.

Now it’s the herbivore’s turn to charge, lowering her head, she rams one of the Gorgosaurus, shoving him over, then she turns her attention to another one, charging towards her, but the carnivore manages to sidestep the attack. The hadrosaur isn’t close to stopping though, she rears up and tries to stomp on the carnivore before trying another headbutt, narrowly missing both times. The Gorgosaurus tries to attack from behind, only for the Parasaurolophus to swing around with her tail, smashing the carnivore hard in the side and knocking her over. The hadrosaur lets out a snort, as if daring the other 4 to continue attacking. With two of the pack already down, the Gorgosaurus wisely back off, leaving the Parasaurolophus to run and try to catch up with the herd.

The two downed pack members will live, but they won’t be able to hunt for weeks. Fortunately, the advantage of living in a pack means that they can get nursed back to health by their pack members.

10 Hours Later

As the sun sets, the Centrosaurus herd continues northward, but overhead lies one of nature’s most spectacular light shows. A geomagnetic storm in the upper atmosphere has created a dazzling display of the northern lights. Massive, green arcs of light dance slowly across the sky, illuminating the mountainous terrain with a lime colored glow.

Even dead set on migrating, the Centrosaurus, Parasaurolophus, and even the Gorgosaurus can’t help but stop and stare at the enchanting display. And unlike a lot of modern mammals, the dinosaurs are able to properly make out the colors of the auroras.

Like modern birds, most dinosaurs are tetrachromats, meaning that they possess 4 different kinds of cone cells in their eyes, and as such, are able to make out and distinguish the colors of red, green and blue, as well as some colors that even humans can’t see, such as ultraviolet. As a result, northern lights look just as dazzling to dinosaurs as they do to us.

2 Weeks Later

3 weeks into the migration, the Centrosaurus have paused to get a drink from a river, here is where the seeds of the herd’s doom are beginning to trickle. The river is noticeably swollen, and the cause of this is meltwater coming from the mountains, as it runs off the mountains, the water feeds into rivers and streams, frequently causing them to flood.

The herd’s days are now numbered.

However, a much more urgent threat comes bursting through the trees, it’s the Gorgosaurus pack, and they’re once again on the hunt. They charge the herd, once again trying to get them to scatter, but there’s a problem, the Centrosaurus have set up shop next to a rocky outcrop that blocks off their escape. And there’s a reason why you never corner a ceratopsian.

Instead of running, the Centrosaurus turn their heavily armed heads towards the Gorgosaurus and begin growling and bellowing. The Gorgosaurus stop the charge before circling the herd, trying to figure out how to attack.

Finally, one of them loses his patience before charging in. And almost immediately he pays the price. A Centrosaurus thrusts upwards with her horn, the the spiked organ easily piercing the Gorgosaurus’ organs, blood spews out of the wound, coating the Centrosaurus’ head. After a second, the Centrosaurus pulls the horn out, leaving the lifeless Gorgosaurus to flop to the ground.

Seeing this, the other three begin retreating. They cannot afford to lose another member of the pack.

The next night

As a thunderstorm blows in, The Centrosaurus are beginning to near their destination, but there is one final hurdle they need to cross. A flooding, swollen river is all that stands between them and their feeding grounds. They have made the journey before, and usually they would simply wait for the flooding to go down, but this time they may not have the option.

A flash of lightning reveals three shapes moving through the forest. It’s the Gorgosaurus pack, and having not eaten in almost 3 weeks, they are desperate for food. They charge the herd, and when another flash of lightning reveals them again, the Centrosaurus stampede. Until they hit the bank of the river, knowing they can’t safely cross, they stop, skidding to a halt on the mud. Panicked and cornered, they have no choice but to hop into the river. But none of them want to take the plunge. Eventually, the Gorgosaurus reach the herd, and this time they aren’t wasting time waiting for them to scatter.

One rushes at one of the Centrosaurus and grabs him by the horn, dragging him away from the rest of the herd. The other two begin attacking as well, with one of them jumping on the ceratopsian’s back and biting at his flanks. Suddenly another Centrosaurus comes in, throwing away two of the Gorgosaurus and allowing the first Centrosaurus to throw off his attacker. The two then run back to the rest of the herd.

Back at the front of the herd, one brave soul finally jumps into the river, and, despite struggling immensely, manages to make it to the other side. This gives the rest of the herd some confidence, and they begin jumping in as well. Until one of them is suddenly slammed hard in the side by debris. Tree trunks, carried downriver by the flood’s current, begin hammering the Centrosaurus, and the panicked herbivores frantically try to turn back, but the ones just entering don’t understand what’s going on, and they keep going forwards, causing the crossing to devolve into chaos.

More tree trunks continue to slam into the Centrosaurus, the sheer force of the blows knocking them unconscious, making matters worse, the panicked herd keeps shoving each other under waves, drowning each other. Even worse, the members at the back of the herd keep piling in to escape the Gorgosaurus, making matters 10 times worse.

One of them is slightly more hesitant about getting in, and that second of hesitation is all the Gorgosaurus need. One of the Gorgosaurus grabs him by the leg, pulling him backwards, the herbivore shakes off the carnivore’s grip and turns to face him, only to get ambushed from the side, the other Gorgosaurus attack him. One grabbing him by the leg and the other grabbing his neck.

The Centrosaurus bellows before the remaining Gorgosaurus grabs him by snout, deliberating placing his mouth over the Cerptopsian’s nostrils, suffocating him.

Back on the river is a disaster, pretty much the entire herd has drowned, leaving behind a floating raft of carcasses. Of the entire herd, maybe 6 have survived, a pitiful end for one of the biggest migrations in history.

1 week later

While the blob of rotten carcasses may be disgusting, it’s an important food source for every carnivore in the region. A Daspletosaurus carefully pulls one of the carcasses to the riverbank, and he is soon joined by a gorgosaurus. Usually these two carnivores can’t stand each other, but with this bounty, they are more than content to share.

Next time on Walking with Dinosaurs: Explore the oceans of the late Cretaceous, seeing how the most dangerous thing to ever swim takes care of her young.

Last Time on Walking With Monsters, we saw monster fish duke it out for supremacy, and the rise of the amphibians in the Devonian, now as we enter the Carboniferous, we will explore a world ruled by bugs.

Chapter 4: Lurkers of the Undergrowth

Time 304 Million Years Ago, Late Carboniferous

Location: England

304 million years ago, Earth almost resembles an alien planet, in this coal swamp, these plants may resemble trees, but they are actually distant relatives of ferns. And these giant ferns are helping to create one of the weirdest periods in Earth’s history.

For the past 200 million years, Earth’s new forests have been pumping huge amounts of oxygen into the air, resulting in an atmosphere with 40% more oxygen than today. And for the Arthropods, this oxygen rich atmosphere has been a supercharger. The ground suddenly moves as an armored carapace raises out of the dirt. This huge creature is an Arthropleura. This animal is actually a member of the millipede family, but she is a long as a car. Despite her size, Arthropleura is a herbivore and prefers fern leaves to animal flesh, and being as big as she is, most predators in the Carboniferous don’t mess with her as she has her breakfast. Arthropleura eat a variety of different plant food, and today, she is in the mood for tree bark.

The bark of these conifer trees is very tough, but Arthropleura has a way around this. A set of powerful mandibles crush though the tough outer layer of bark, allowing her to eat away at the softer inner layer.

However, even in this alien place, familiar faces are starting to appear. This is a Pulmonoscorpius, a huge scorpion, at 2 feet long, he could hunt possums if he were alive today. They are ambush predators, hiding in the plentiful bushes to ambush their meals. Meals such as this Petrolacosaurus, this lizard like animal is one of the earliest reptiles, and he has an advantage over his amphibian ancestors. Unlike amphibians, with their thin skin, Petrolacosaurus has a tough, scaly hide, this thick skin is much better at retaining water, allowing him to venture further away from the rivers the amphibians are confined to.

However, unlike the exoskeletons of his arthropod contemporaries, scales aren’t much good at fending off attacks, as he is about to learn the hard way. The Pulmonoscorpius suddenly lunges out of the bush and grabs the Petrolacosaurus by the tail with its pincers before stinging the reptile. The Petrolacosaurus’ thrashing is quickly reduced to small twitches as the venom takes hold, digestive enzymes begin to dissolve his innards, turning him into a sort of smoothie that the scorpion slurps up. This is a world where bugs eat lizards.

Pulmonoscorpius sensed the reptile’s approach with special sensory organs on its underside called pectines, these organs drag across the ground, sensing vibrations from approaching prey or predators, and allowing the scorpion to respond accordingly. Soon however, the scorpion picks up a much larger set of vibrations.

It’s the Arthropleura, who is making her way down to the swamp to drink, but the Pulmonoscorpius raises his tail and pincers in a defensive posture. However, the giant millipede decides the scorpion’s next move for him, she crawls over top of the scorpion, and the shocked arachnid frantically tries to sting the millipede. But it is all for naught as the Arthropleura’s armor proves simply too tough for the stinger to punch through. This mighty predator of the swamp forest is now treated as nothing more than a speed bump.

The Arthropleura makes her way to the lake, where more strange creatures are awaiting. These are Neopteroplax, a huge amphibian, at 6 feet long, they are the only creature here that rivals Arthropleura in size. But they are not the only ones here. This spider-like creature is an Uraraneid, an arachnid the size of a cat. But despite appearances, he is not a spider, though he is closely related.

Uraraneids are thought to be the ancestors of spiders, and it’s easy to see the resemblance, like a spider, they possess eight legs and fangs, but unlike a spider, they lack venom and spinnerettes. They also have a vestigial tail sprouting from their abdomen, a leftover from their scorpion-like ancestors.

This male Uraraneid is searching for a mate, like modern tarantulas, male Uraraneids don’t stay put in a burrow like the females, instead wandering around above ground searching for food and mates. But this is a dangerous world for the Uaraneid.

A Pulmonoscorpius suddenly lunges out of a bush, pincers barely missing the smaller arachnid. And in the Uraraneid’s panic, he rushes straight into another threat, the Arthropleura, she may be a herbivore, but she is still a nearly hundred pound beast that can trample smaller creatures underfoot. The Uraraneid books it, managing to get out of the giant millipede’s way.

Once he’s sure he’s safe, the Uraraneid returns to the task at hand, finding prey. Like today’s wolf spiders, Uraraneids possess quite large and developed eyes which allow them to spot prey. A centipede, they too appeared before the dinosaurs, and adults can reach up to four feet long, but this 2 foot long juvenile is easy meat. The Uraraneid pounces, massive 3 inch long fangs plunge into the centipede’s body. Uraraneids lack venom, but the sheer size and power of their fangs is more than enough to make up for it. However, after making sure his victim is dead, another threat arises. A Neopteroplax lunges out of the water, snapping at the arachnid, a reaction time of less than half a second is the only thing that keeps the Uraraneid from becoming lunch.

Now further away from the water, the Uraraneid doesn’t eat his catch, instead dragging it away, and this is why. A female’s burrow. When he reaches it, the Uraraneid drops the centipede starts drumming the ground with his pedipalps, and it doesn’t take long for him to get a reaction. She is nearly twice his size, and sensed his drumming with sensory hairs lining her legs. The male continues to drum, mimicking the vibrations of a prey item. The female lunges, but the male sidesteps, causing the female to grab the centipede instead. So far, things are going according to plan for the male. By gifting the female with food, the male distracts her from himself while they mate.

Using the distraction, the male slips under the female’s abdomen, and he begins rubbing his pedipalps along her underside, by doing this, he deposits sperm that fertilizes her eggs, producing the next generation. However now he’s run into a problem, getting away, usually the female would still be eating her food, allowing the male to slip away undetected, but this time, the female lost interest in the centipede, and now her attention is focused solely on him. The male has to pick the exact right moment to make his getaway. Suddenly he bolts, and the female spins on her heel, but she’s missed her mark.

This time, the male survives to fight another day, in time, he will mate with other females, spreading his genes and continuing the species. Suddenly the Uraraneid is snatched up by six spiky limbs, and the attacker swiftly flies away.

This is the giant dragonfly Meganeura, the first ruler of the skies, and being nearly the size of a sea gull, she is one of the largest flying insects to ever exist. Dragonflies and their relatives are the first animals to take to the sky, and are by far the best fliers out there. Their four wings flap independently, allowing for speed and maneuverability that won’t be matched until hummingbirds appear in 304 million years time. As the dragonfly alights on the side of a tree, her weapons get to work, sharp, powerful mandibles make short work of the Uraraneid’s exoskeleton, while spined forelimbs hold him down.

———

Down on the river banks, the Arthropleura is just about to leave, but such a large potential meal has not gone unnoticed. Most of the Neopteroplax know not to mess with an Arthropleura, but this young female never got the memo. The large amphibian rushes out of the water, but the giant millipede rears up, heaving almost half of her eight foot long body into the air, and hisses. In a manner similar to modern hissing cockroaches, Arthropleura can force air out of breathing spiracles in its exoskeleton to produce a hissing sound, it’s one of the first invertebrates to have a voice. However the Neopteroplax is undeterred, and lunges for a bite. As soon as the amphibian clamps down, the Arthropleura starts thrashing violently, it may look like mindless panic, but in reality it is a fighting strategy, sharp, axe-like blades protrude from the Arthropleura’s flanks, these can smash into the skin of an attacker, and in her thrashing, the Arthropleura lands several good blows.

The Neopteroplax doesn’t seem to realize the danger she’s in. Realizing that her bite isn’t having much effect, she shifts her grip, intending to drag the Arthropleura into the water, but the giant millipede has other ideas, and the Neopteroplax’s move has left her right in the strike zone of her other defense. The Arthropleura curls around and clamps down with her own mandibles, they aren’t as big as the jaws of the amphibian, but they have an immense amount of power behind them, with a bite force of 1,100 PSI, equivalent to that of a hyena, they can easy bite through tree bark, or crunch bone

And the millipede’s jaws slam shut around the Neopteroplax’s eye, in seconds, the powerful jaws crush through the amphibian’s eye socket, ripping the eyeball out in the process. Blood spurts from the wound as the Neopteroplax immediately lets go and tries to flee to the water. But the Arthropleura isn’t letting go, and with 60 legs, she has the edge in this tug of war. Finally the Neopteroplax breaks free by tearing away from the Arthropleura, leaving her mangled eye dangling in the millipede’s grip.

The Neopteroplax has thoroughly learned her lesson as she frantically clambers back to the water. Her wound will heal, but she will be visually impaired for the rest of her life. However in the water lurk even more strange creatures.

Stalking among these water plants is a freshwater eurypterid, Megarachne. This sea scorpion was thought to be a spider when it was first discovered, hence the name ““giant spider”. But when more complete fossils were found, scientists realized that instead of the world’s biggest spider, it was actually a eurypterid, and on the small side for one at that. Unlike its ocean going relatives, Megarachne can’t swim, but he doesn’t have to. The Megarachne starts dragging his front legs through the sediment, bristles on the legs allow the eurypterid to filter small animals out of the sand, and the trapped microbes are brought back up to the mouth.

———

As night falls, the Arthropleura prepares to bed down for the night, burying herself in the leaf litter. And as the giant beds down, night reveals some more familiar faces.

These are Archimylacris, an ancient relative of today’s cockroaches, there are already family resemblances. And they have a special relationship with Arthropleura, the roach relatives begin crawling over the Arthropleura’s carapace. As she forages, Arthropleura picks up all kinds of parasites that irritate her, and it’s the Archimylacris’ job to get rid of them. They begin cleaning the giant millipede, picking off the parasites and eating them. This sort of relationship benefits both sides, the Arthropleura gets parasites removed, and the Archimylacris get a meal.

As the Arthropleura gets cleaned, something else is on the rise. Something that will change the face of the world forever. And a small Petrolacosaurus is the ancestor of it.

As millions of years pass, relatives of Petrolacosaurus grow larger. They jaws become more powerful, filled with razor sharp teeth. Their legs transition from a splayed posture to a more erect gait, allowing them to run faster to chase down prey. Believe it or not, this strange looking creature is destined to become the ancestor of the dinosaurs.

Next time on Walking with Monsters: We see how life on earth overcomes the biggest mass extinction of all time, and see what exactly leads to the dinosaurs.

Last Time on Walking With Monsters: We saw the arthropods and plants take their first fateful steps onto land. Now the vertebrates will do the same, and we will also see the most dangerous fish to ever live.

Chapter 4: Amphibian’s Beginnings/King of the Ocean

Time: 362 Million Years Ago, Late Devonian

Place: Canada

Midday in a late Devonian forest, yes, forest, land plants have evolved much since the early stalks of the Silurian, sprouting into strange, alien looking forms unlike anything alive today. Accompanying these strange plants are some of the first land dwelling vertebrates.

This is Ichthyostega, one of the earliest amphibians, and an evolutionary breakthrough. Amphibians are the first vertebrates to have proper legs and feet, allowing them to actually stand up and walk compared to the glorified thrashing of their lobe-finned ancestors, their more advanced lungs allow them to take in the air and pump it in and out, unlike an arthropod and more like us. Humans, along with every tetrapod alive today, still use this simple system to breathe.

However, Ichthyostega is not yet completely adapted for land based living. Just like today’s amphibians, their skin is thin and needs to be kept wet, meaning that they need to take frequent trips to the water. And in the water lurk the some of the scariest fish of all time.

———

Underwater during the Devonian is very similar to land, with various animals all scuttling around, trying to survive. But a new kind of fish has appeared in these waters, the placoderms. These armored fish are the first to have biting jaws, allowing them to tackle bigger prey and process food more efficiently than their jawless competitors. And one species has taken this setup to extremes never seen before or since.

Suddenly, in less time than it takes to blink, a massive jaw sucks in a eurypterid and crushes its carapace into dust, leaving the sea scorpion’s head to sink to the ocean floor. It seems the sea scorpions have been outdone by the new kids on the block.

This magnificent beast is Dunkleosteus, a 3 meter long placoderm, and its chubby build hides some devastating weapons. Those bony white shears are fused teeth, forming the first beak. Under the skin, massive jaw muscles can open the mouth and close it again in less time than it takes to blink, producing enough force to slice through bone like paper.

It was once believed that these fish had long, shark like bodies, but is now know that this wasn’t the case. Via analyzing the bodies of some of Dunkleosteus’ close relatives, scientists have deduced that Dunkleosteus likely had a short, plump, yet muscular body shape, more similar to that of a largemouth bass rather than a shark. This makes Dunkleosteus capable of quick bursts of speed, perfect for an ambush predator.

But this particular Dunkleosteus isn’t just plump by design, she’s pregnant, like some modern sharks, most placoderms give birth to live young, and Dunkleosteus in particular travel thousands of miles to their spawning grounds in shallow lagoons, where their young will be safe.

The time has come for this female to begin her journey, and she may not see another shoreline for a month.

———

Back on land, problems are arising for the Ichthyostega. It has not rained in weeks, and now the rivers are beginning to show the effects of it. They are far lower than normal, and it creates a huge problem for the amphibians.

As mentioned before, they need to keep their skin wet at all times in order to survive, which means that they need constant access to water. As you can imagine, it means that they get hit particularly hard by droughts. However, they do have a solution to this.

One of the Ichthyostega begins rolling around in the mud, followed by more of them. The mud protects their skin from the sun, as well as dampening the skin itself. But just mud will only get them so far. Soon, they will have to move to a new lake.

———

The Dunkleosteus has decided to make a quick rest stop on her journey, a 13 foot long fish needs food to stay alive, and nowhere is that more abundant than at an estuary, where a river meets the sea. Here we find some familiar faces.

This is Cladoselache, and as you can probably guess from its appearance, it is a primitive shark, however, at only two feet long, it is far from the top predators it will give rise to.

In a split second, the Dunkleosteus snaps it up, leaving nothing but a severed head and a cloud of blood.

The reason Dunkleosteus is able to snap its jaws so fast is thanks to fast twitch muscles in its jaws, allowing to open and close its mouth in less than a second. As a result, it has the strongest bite force of any fish, living or extinct. This, combined with the razor sharp beak, make for one of the deadliest weapons in the history of life on earth, able to shear through bone as if it were paper.

They need this kind of weaponry, because pretty much everything is armored in these oceans.

Down below the Dunkleosteus is a group of armored fish. These are Bothriolepis, peaceful bottom feeders, and believe of or not, they are related to Dunkleosteus, and the two are part of the same family, the placoderms.

Placoderms are the first fish to have jaws, but they are all defined by one feature, a heavily armored, bony skull. They are the first fish to incorporate actual bone into their skeletons at all, as most other fish at this time only have cartilaginous skeletons. It is believed that this bony skull is the forerunner to the bone skeletons of bony fish, making placoderms ancestral to most fish species alive today.

Dunkleosteus however doesn’t care about what it’s kind will give rise to. To her, anything that can fit in her mouth is food. And she needs a lot of it, since she’s eating for two.

She lunges into the school of Bothriolepis, and she opens her jaws, the resulting suction allows her to eat up to three at once. Her powerful beak crunching through the armor with ease. Soon enough, the estuary is strained blood red.

With her belly full, the Dunkleosteus swims off, but not before suddenly vomiting up a bunch of crushed bone.

Similarly to today’s owls, Dunkleosteus cannot digest bone, so she has to regurgitate it back up whenever she eats.

———

Back on land, the last of the Ichthyostega’s river has completely dried up, and as a result, the amphibians are being forced to migrate to a new one. But There’s a reason they are so reluctant to change rivers.

Ichthyostega are similar to hippos in that they are incredibly territorial, males hold on to their rivers and harems of females, and viciously defend them from intruders, even if said intruders are simply trying to find a new home.

Reluctantly, the Ichthyostega begin their march to find a new river. To prevent from drying out, their skin produces a thick covering of mucus to protect their sensitive skin from the sun. It won’t last forever, but it’s better than nothing. However, It may take hours before they run into another water source.

———

The Dunkleosteus is nearing her destination, a small, shallow lagoon close to shore, it is here that she will give birth to her young. But as she begins to enter labor, a hurdle shows up.

Dunkleosteus mothers can get extremely moody during labor, to the point that any imagined threat can send them into attack mode, and our female already bears several scars caused by fights. It isn’t long before a rival female shows up.

The problem is that Dunkleosteus are both cannibals and extremely protective of their young, as it maximizes their gene pool’s chance of survival, while minimizing that of others. However, it also means that any other Dunkleosteus in the vicinity is perceived as a threat.

The rival bullrushes our female, ramming her hard with her armored head before biting into her flesh, removing a small chunk of it.

The female attempts to retreat, but the rival gives chase, trying to nip at her tail fin, but the female dives down before rushing back up, ramming her rival in the stomach.

The two fish swim alongside each other, each trying to get in a bite, until finally, our female’s had enough. Swimming away to get a better angle, she charges back in, before biting hard into her rival’s side, blood spurts out of the wound and fills the surrounding water. Then the female rips away a chunk of flesh, in the process pulling out a part of the rival’s intestine,

Severely wounded, the rival begins to sink, weighed down by her heavy armor, her organs spill out of the wound as her lifeless body sinks into the depths. It’s not often that Dunkleosteus fights end in fatality, but when they do, it’s often a gruesome end for the loser.

Victorious, our female is free to give birth, and it isn’t long before she does. After a few minutes, the youngster finally arrives, his head armor is still soft, but it won’t be long before it hardens. His mom will protect him for a few days, and after that he is on his own, completely independent.

———

After hours of wandering mostly aimlessly, the Ichthyostega have come across a bounty.

A massive lake, far larger than their old river. This one must never dry out, even in the harshest drought. The amphibians waste no time diving into the water and wetting their skin. But it isn’t long before the original owner of this lake notices.

The lead male is suddenly assaulted from the side, it’s the resident male, and he’s not willing to share his lake with anyone. The two males duke it out, fiercely striking and biting at each other, the resident male may be older, but our male has youth and agility on his side. The two amphibians go underwater, but now, our male has the advantage.

He bites one of the resident male’s legs before rolling like an alligator, dislocating the limb before letting go.

Severely injured, the resident male retreats, swimming away with a trail of blood behind him.

As our male surfaces however, a seemingly insignificant spectator is set to give rise to the strangest period in earth’s history. A millipede feasts on some fern leaves, unaware of what his future holds.

As millions of years pass, the millipede’s descendants grow larger and stronger, their exoskeletons almost impenetrable. They continue to grow larger, eventually becoming the largest land arthropod on earth.

Next Time on Walking With Monsters: We explore a day in the life of one of the largest arthropods to ever exist, seeing what the strangest period in earth’s history was really like.

Last time on Walking With Monsters: We saw the rise of the sea scorpions as they waged the war against the Nautiloids. Now with their arch rivals weakened by the Mass extinction at the end of the Ordovician, the spot of top predator is open for new management, and the eurypterids are keen to take that spot.

Chapter 3: Water Dwellers III: Age of the Sea Scorpions (wow that’s a mouthful)

Time: 428 Million Years Ago, Middle Silurian

Location: Florida

428 million years ago, the residents of Florida are very different. Strange creatures roam this land, doing strange things with one purpose. Survive. Actually they might only be a little different. Anyway, in these waters are huge predators laying in wait for their next victim to lurk too close.

A brontoscorpio, a massive aquatic scorpion roams the sea floor. But suddenly a huge claw rises out of the sand and grabs the scorpion, crushing it between the pincers. Another claw reaches out, grabbing the brontoscorpio’s tail. This is no gator, this is Jaekelopterus, the largest arthropod of all time. At 9 feet long, it dwarves the 2 foot brontoscorpio and rivals the modern alligator in size.

Like Megalograptus before it, Jaekelopterus is a eurypterid, a relative of spiders and scorpions. And like them it is a fearsome predator, the great pincers are for crushing and dismembering prey, but there is more to this predator than meets the eye. Looking on the huge creature’s underside reveals a mass of squirming offspring. This monster is a mother.

Like modern scorpions, Eurypterids give birth to live young, and for the first few months of their life, they cling to the underside of their mother, protecting them from predators.

Using her pincers, she crushes the Brontoscorpio’s body, blood and mush spews out of the crushed arachnid as the exoskeleton splinters. Then she pulls the Brontoscorpio apart, dropping the head to the ground. Sensing food, the young Jaekelopterus release themselves from their mother and start swimming towards the mangled Brontoscorpio.

Like other Eurypterids, Jaekelopterus has a somewhat strange feeding setup. Between the two large pincers are a much smaller set of claws, which it uses to mash up the meat, after which, the claws bring the food to the underside of the creature, where the mouth is located. Unlike modern insects, there are no mandibles or jaws to aid in chewing, just a simple hole that leads to the esophagus, so the claws more or less just kinda shove the food in there. After which, the esophagus carries the food into the stomach. It’s a strange setup, but it gets the job done.

———

Land during this time is a strange place. It was once thought that plants didn’t fully colonize the land until later in the Devonian, but this is now known to have not been the case. Moss has advanced much since the late Ordovician, where it was once confined the edges of waterways, it is now found growing far inland, and they are not the only plants here.

This strange looking thing is Cooksonia, the first of the vascular land plants, and while it is only as tall as one of your fingers is long, it’s design will one day lead to the tallest redwood. It is the first plant to contain vertical vessels inside its stem, as well as the first to have roots that dig into the soil rather than cling onto it. Because of this, it can get much taller than its surrounding competitors. The green color of its stem is caused by chlorophyll, a chemical that allows the plant to create its own food by combining CO2 with sunlight, creating sugar and oxygen, the latter of which is released into the air.

But these plants pale in comparison to the biggest organism from the Silurian.

This is not a tree, this 24 foot tall ‘plant’ is actually a type of fungus called Prototaxites, and it’s existence is key to the existence of life on land. Under the earth, Prototaxites is supported by hundreds of thousands of long, threadlike filaments, these work to break down organic matter, feeding the fungus and producing something else crucial to the survival of plants. Rich, fertile soil. This soil provides the perfect nutrients for plants to grow and colonize the land. It is thanks to these giants that we are able to marvel at the flowers in our garden today.

Joining them are the first true land animals, primitive millipedes such as this Kampecaris are the first animals to live entirely out of water, along with their relatives the centipedes.

———

As night falls, the Jaekelopterus family once again disappears beneath the sediment, and soon enough, the night shift emerges. And as always, the trilobites are center stage.

These trilobites are called Dalmanites, and they are spawning.

Trilobite courtship is the inverse of most courtships today. It’s the females who attract males, and they do it in a unique way. The trilobite drums her legs against the ground, using a distinct rhythm unique to her species, they do this to avoid getting their sounds mixed up with the sounds other trilobites make.

It isn’t long before she’s noticed, but it isn’t the attention she was hoping for. It’s another female, and she wants this spot. Trilobites can be very territorial, and the encounter very quickly turns into violence.

The two trilobites start shoving each other, demonstrating their strength in a non-lethal manner, their aim is to flip the other one over. And our female appears to be winning, barging her opponent backwards. Finally, she scoops the rival onto her carapace and throws her over, winning the battle.

Our female then turns around to collect her prize, a male, attracted by the drumming and ensuing fight.

Nearby, the rival manages to flip herself over and begins to retreat, but unwittingly stumbles into someone’s bed. A claw suddenly shoots out of the sand and grabs the trilobite before squeezing.

Hard.

Unable to handle the pressure, the trilobite’s shell pops open like a soda can, sending the trilobite’s organs rocketing out of her backside. Finally, the Jaekelopterus emerges from the sand and begins eating away at her midnight snack.

———

The next morning, the Jaekelopterus emerges to find a bounty, an entire shoal of Cephalaspis, a type of primitive jawless fish, all traveling upriver to lay their eggs. It’s the perfect opportunity to teach her young ones how to hunt.

The young Jaekelopterus again release themselves from their mother before burying themselves in the sediment. Cephalaspis are too small to be much of a meal to the mother, but for the babies, they are perfect.

One of the youngsters lunges out of the sand, his claws outstretched, only to miss his mark.

Another one lunges, this one actually manages to grab a Cephalaspis, but her claws slide off of the fish’s armored head.

Yet another has a go at the fish, but he only manages to grab the Cephalaspis’ tail, and the fish quickly struggles out of his grip.

Another one strikes, and finally, she seems to have gotten a good hold on one of the fish, then she copies her mother, squeezing with all her might. Under that kind of pressure, it only takes a second for the Cephalaspis’ belly to split open, guts spilling out of its body cavity.

As the sophomore killer settles into her meal though, a rival is on the rise.

———

This is Parayunnanolepis, a primitive placoderm, and despite its small size, its design will become the baseline for one of the most iconic groups of fish ever.

As millions of years pass, fish similar to Parayunnanolepis grow to potentially overthrow the sea scorpions as top dogs. They grow massive, muscular bodies, their gills slowly change into the first jaw. As they grow larger and more predatory, weapons are required for slicing up prey. The first teeth appear.

With these new additions, the fish are prepared to finally take a strike back at their arthropod oppressors.

Next Time on Walking With Monsters: We explore the late Devonian, seeing the first amphibians rise on land, as well as the king of fish rule the sea.

Last time on Walking With Monsters: We saw the beginnings of the arthropods in the Cambrian seas, and how they adapted to natural disasters and volcanoes. Now we see how they hold up against the very first mass extinction.

Chapter 2: Water Dwellers Part II

Time: 445 Million Years Ago, Late Ordovician

Location: North America

Mid day over a late Ordovician reef, and some animals are beginning to take on forms similar to today. Corals have existed since before the Cambrian explosion, and have formed reefs since then as well. Just like today, coral reefs are basically an oasis in the ocean, but instead of fish and crabs populating these places, we find nautiloids and trilobites. However, coral reefs like these are an endangered species in the Late Ordovician, for the world is currently in the grips of a mass extinction. 250,000 years prior, a gamma ray ray burst slammed into Earth, stripping the ozone layer of the atmosphere away, as the oxygen molecules mixed with nitrogen in the atmosphere, it created nitrous oxide, a toxic smog encircling the Earth and tainting the sky a sickly brown color. What’s more, Nitrous oxide blocks sunlight, preventing the warmth of the sun from reaching the planet, and causing an ice age.

Corals do not handle temperature changes well, and when the temperatures start dropping, algae that live the coral detach and float away. This makes the coral lose its color, turning the once vibrant reef into a ghostly white graveyard.

This reef is one of the last holdouts in this Ice Age. However, in one of the coral caves lurks one of the new kids on the block.

This lobster like arthropod is a Megalograptus, one of the earliest sea scorpions, also known as eurypterids. Despite appearances and names, she is not actually a scorpion, but a closely related family. Arthropods similar to Megalograptus will eventually give rise to the scorpions and spiders of today.

However, just like modern scorpions, eurypterids have to shed their skin in regular intervals. Their hard exoskeletons do not grow with their bodies, and so they have to squeeze their way out of it, growing a new, bigger shell in the process. As uncomfortable as this process appears, it’s actually a very relieving, if taxing, experience for the Megalograptus. And a few hours after freeing herself from her old skin, her new shell is hardened and ready to go.

The first thing on the list is to find food, and for Megalograptus, that means primitive fish, such as these schooling Astraspis. Unlike most modern fish, Astraspis and its relatives lack biting jaws or teeth, their mouths are more or less closable holes in the middle of their faces that they suck food through. They are prime targets for the Megalograptus, but as the eurypterid readies for an attack, something else looms overhead that scatters the Astraspis.

It’s a Cameroceras, a huge relative of today’s squid and octopus, but unlike them, it has a shell reaching up to 20 feet long, and it is the only thing in these waters capable of preying on Megalograptus. The sea scorpion books it, Eurypterids can swim at speeds up to 19 miles an hour, and would leave an Olympic swimmer in the dust. However Cameroceras is faster, thanks to a siphon on the underside of their bodies, identical to the ones on modern squid and octopi, they can cruise along at 30 miles per hour in short bursts.

However, the Megalograptus has one thing on its side, agility, while Cameroceras is faster in straight lines, it’s own massive shell becomes a handicap when maneuvering around tight turns, needing to slow down in order to swing the rigid shell around, meanwhile the Megalograptus’ more flexible exoskeleton allows it to turn on a dime without having to slow down first, this gives the Megalograptus the edge in a high speed chase.

The Megalograptus dives into the coral, twisting and turning through the tight pathways with ease, the Cameroceras follows, but has a much harder time maneuvering itself through the channels. However it manages to keep pace with the Megalograptus, so the sea scorpion uses a fool-proof strategy. She bolts into one of the caves in the reef. Against a modern octopus, this move would be a death sentence. But once again, Cameroceras’ huge shell works against it. However, the armored cephalopod has one trick up his sleeve. He slips a tentacle into the cave, groping around for his meal. Fortunately, the Megalograptus is deep enough in her hiding spot that the Cameroceras cannot reach her. Knowing that he’s lost this confrontation, the Cameroceras is forced to settle for a trilobite instead.

Unlike Megalograptus’ somewhat thin and fragile spikes, Cameroceras hunts with a powerful beak that can crush through arthropod exoskeletons, this allows Cameroceras to eat whatever it wants in these seas. But these magnificent predators are the ones hit hardest by the Ice Age, food is becoming scarcer by the year, and these huge predators need an equally huge amount of food to keep themselves alive.

Megalograptus, and most other sea scorpions, however, are faring much better, because of their smaller size, they don’t require as much food, and scrape by with fewer meals than their larger competitors.

A Few Hours Later

Down on the sea floor, activity is stirring. An entire carpet of trilobites is patrolling the ocean floor, they have emerged from the depths to lay their eggs, but they have a unique place to put them. The carpet waits anxiously at the shoreline, until one bold female makes the first move. These trilobites are some of the first creatures to come out and walk on land, the pioneers may not breathe like we do, but their anatomy is better suited to the oxygen poor conditions of the Ordovician. Whereas vertebrate lungs are fleshy sacs that expand and contract when we take a breath, trilobites use a more primitive organ called a book lung, rather than pumping oxygen, they simply absorb the gas into their blood.

Though their book lungs are perfectly suited for the stagnant atmosphere, their legs are far less so, they are designed to gracefully scuttle across the sea floor, where the trilobite’s weight is greatly reduced by the buoyancy. But on land, there is no buoyancy, and the legs are forced to haul the arthropod’s full weight with no assistance, and the trilobites move in a series of slow lurches. Regardless, the system gets the job done, even if the experience is exhausting for the trilobite.

The trilobites pick their spots carefully, in order for their nesting strategy to work, their eggs need to be away from the water during the regular high tide, but close enough that they will be washed away with the spring tide. Now the trilobites begin digging, fortunately this part is easier than walking, and by doing this, they protect their eggs from the sun’s harsh rays.

As the trilobites haul themselves back to the water, they run over a set of much smaller pioneers, primitive moss. These small plants are a giant leap for the plant kingdom, they are the first ones to grow on land, but they are very different from the familiar grass and trees of our day. Firstly, they lack the vascular stems of most other plants, meaning that they cannot grow as tall as ferns, since they would dry out if they did so. Second, they lack roots, instead remaining attached to the rock with small threads called rhizoids.

They may be small, but this patch of moss will eventually give rise to huge forests. Even the tallest redwood in California can trace its roots (no pun intended) down to these small plants.

The next day

Trouble is brewing on the reef. In the late Ordovician’s unstable climate, powerful storms can develop and show up without warning, and overnight, one of these storms has blown in, and strong winds have whipped the ocean into a frenzy.

Powerful underwater currents bash helpless animals against the sharp coral either beating them to death outright or fatally wounding them. For smaller animals like trilobites and Megalograptus, they can hide in the reef until the storm passes. But for the larger Cameroceras, there is nowhere to hide, so they do what most modern sea animals do, head for deeper water, but this brings a different problem.

As you head deeper into the ocean, water from above presses down on you, crushing harder with each foot deeper you go. For the Cameroceras, their shells become another weakness.

In less than a second, the water pressure crunches the shell into dust. Like a snail, the Cameroceras’ organs are stored in their shells, so such an injury is completely fatal. Fortunately though, death comes quick.

More Cameroceras begin imploding, their crushed shells turning into a calcium rich shower for any animals below. The result is a floating raft crushed bodies with organs dangling out of them.

Back on the reef, smaller animals seek shelter, but one trilobite has been caught in a particularly unfortunate situation. Holed up in a cave, it has just recently molted. Its exoskeleton hasn’t hardened yet, and that is very bad news. Chased into the cave by the storm, the Megalograptus has found it, and it is not about to pass up a free meal.

The eurypterid grabs the trilobite, its spines easily piercing the softened exoskeleton.

Several Hours Later

The aftermath of the storm makes the reef look unrecognizable, shattered pieces of coral litter the ocean floor, while the mountains of rubble they used to be attached to lay broken and desolate.

However, creeping out of the wreckage is a survivor, the Megalograptus, followed by more of her kind. Able to squeeze into caves to hide from the worst of the storm, the sea scorpions have survived the storm, and awaiting them is a banquet. The female from earlier swims up to the surface to find the dead Cameroceras. Using her spiked limbs, she grabs the mangled corpse and drags it down to the sea floor before beginning to feed on it. Digestive juices secreted from the eurypterid’s mouth begin dissolving the crushed nautiloid’s innards. The hunter has truly become the hunted.

Megalograptus’ story doesn’t end here, as it is only the first in a long line of Eurypterids.

As millions of years pass, Eurypterids build on their simple yet effective design, in place of needle-like spines, powerful pincers take their place. They become larger and stronger, giving them the ability to go after tougher prey. With these improvements, the sea scorpions seem poised to become the next big predators.

Next Time on Walking with Monsters: With their nautiloid rivals extinct, Eurypterids are primed to become the top predators in the Silurian seas, join us next time to see how the largest arthropod of all time watches over her young.

AN: I hope you liked my attempt at including the Evolution Cutaway at the end, it’s hard to do in writing, but I think it turned out okay.

Time: >1 Billion Years ago

This is earth, 4 billion years ago, this is not the lush planet we know today, but a scaldingly hot, volcanic wasteland covered in a sea of lava. Clouds of toxic fumes choke the atmosphere, volcanos vomit magma onto the rocks, and sulphuric acid rain falls onto the scorching surface. This world has no hope of ever developing life, but that is all about to change.

Thea, another planet as big as Mars, slams into Earth, sending pieces of debris everywhere. A ring of molten rock forms around the reforming Earth, forming our moon. In time, comet impacts bring water to the cooling planet. But who will inherit these new oceans?

In this series, we will take a look at the extraordinary story of life before the dinosaurs, a time full of strange and unique creatures, all fighting a desperate battle to rule the world, in the process forming not only the blueprints for our bodies, but for everything alive today. Among these beasts were our own ancestors, whose survival determines whether humans will exist at all.

This is the forgotten story of an epic war for our world. A war fought by monsters.

Chapter 1: Water Dwellers Part I

Time: Middle Cambrian, 512 Million Years Ago

Place: Unknown

Over 300 million years before the first dinosaurs appeared, the world is a very different place, what will one day be continents are unrecognizable islands of rock, land plants do not exist yet, meaning the atmosphere is a choking blanket of carbon dioxide. As of now, conditions on land are far too harsh to support life, but in the water, it’s a different story.

Even this early in time, life has already existed for several million years, these jellyfish are one of the most primitive life forms in these oceans, but during the Cambrian Explosion, it doesn’t take long for species to become obsolete. A pair of spiked, tentacle like appendages suddenly grab the jellyfish.

This monstrous being is an Anomalacaris, the world’s first apex predator. Covered in a hard shell called an exoskeleton that protects him from the jellyfish’s stinging tentacles, and armed with spiked raptorial limbs that dig into flesh, he is essentially unstoppable in the Late Cambrian seas. His success in hunting is brought about by an organ that we take for granted, eyes. Granted, these primitive compound eyes can only see blurry, monochrome images, but they are revolutionary in this primitive ecosystem, unlike jellyfish, which float blindly along the current and can only catch things that happen to run into them, Anomalocaris can actively spot and chase down prey.

However, in the endless arms race of predator vs prey, quite a few other Cambrian animals have developed eyes, such as these trilobites. Trilobites bear a great resemblance to modern horseshoe crabs, and they share similar niches, like horseshoe crabs, trilobites are bottom dwelling scavengers, snapping up small scraps from the ocean floor. Trilobites, along with the predatory Anomalocaris they share these waters with, form the ever successful family of Arthropods, which will one day give rise to the familiar bugs we know today, such as centipedes, spiders, and cockroaches. Every insect, arachnid, and crustacean species alive today have their roots firmly planted in this strange world.

The trilobites’ armored exoskeletons are even harder than those of Anomalocaris, and keep them firmly off the hunter’s menu, as Anomalocaris’ mandibles are too delicate to crush exoskeletons, and this protection leaves the trilobites to tend to more important matters. This rotting corpse is a Tamisiocaris, a relative of the predator Anomalocaris, but there is one key difference. Besides the size difference, Tamisiocaris possesses more feathery spines on its appendages, which it would use for filter feeding plankton out of the water. But now that this great creature is dead, it itself is now food. After all, nature always recycles.

The trilobites begin crawling over the the carcass, using their antennae to feel for weak spots in the exoskeleton, their jaws are strong, but not quite that strong. Finally, a crack signals a breach in the exoskeleton. All of the trilobites gather around the crack, each trying to get at the succulent flesh underneath.

———

Nearby, the Anomalocaris has discovered an intruder, she may be a female, but it is not mating season, and Anomalocaris are very territorial. The two predators circle each other, each waiting for the other to make a mistake. The male lunges first, lurching towards the female and ramming her hard in the side. The female quickly gets the message, swimming away with her figurative tail between her nonexistent legs.

The male has defended his territory for today, but trouble is brewing down below.

Deep below the ocean floor, the earth’s surface is split into several huge slabs called plates, these plates constantly press against each other, creating enormous pressure. When one slips, that pressure is released as an earthquake.

The clock is ticking for the reef.

———

On the reef live more strange animals, the Cambrian is a time when life, for lack of a better phrase, threw crap at the wall to see what stuck. And nowhere is that more apparent than with Hallucigenia. Looking like a mix between a sea pig and a porcupine this little creature has caused scientists quite a headache. When it was first discovered, scientists thought that the spines on its back were actually its legs. It took until 1991 for the creature to be depicted right side up. Around then, it was also discovered to have small pincers at the end of its legs, which it used to grip surfaces. The tentacles under its head are used for feeding, dragging small scraps of food to its tiny hole of a mouth.

Hallucigenia isn’t the only strange creature in these waters. This Tuzoia can only be described as a centipede with a clam shell on its back, it can retreat inside this shell should it be menaced by a predator.

However, even in this alien world, some animals would be recognizable today, primitive clams first appeared in the Cambrian, and they look almost exactly as they do today, a prime example of the phrase ‘if it ain’t broke, don’t fix it.’

Sea snails have also appeared, along with their relatives the sea slugs, though it will be another 200 million years before they make their way onto land.

However, all of these animals have one thing in common, they are all invertebrates, they lack a backbone, or any bones in general, quite unlike the fully developed skeletons that many animals have today. So where are the ancestors of the vertebrates you may ask? Back near the carcass is where we find out answer.

———

Back at the Tamisiocaris carcass, the trilobites’ scavenging has attracted company. Small black specks swarm around the trilobites, eagerly munching up what the arthropods leave behind. These tiny animals, no bigger than your thumb, are an evolutionary breakthrough. These are Haikouichthys, the very first fish. It may lack fins or even jaws, but this tiny fish is the ancestor to all vertebrates living today. You see, Haikouichthys is the first animal to have a true backbone, it’s not made of bone, but rather of a softer, more flexible material called cartilage. This cartilage rod allows muscles to attach to it, making this tiny fish faster and more nimble than its arthropod competitors at the expense of defense. They lack an exoskeleton, and so have to rely on their speed to escape potential predators.

As the scavengers feed however, the tectonic turmoil beneath continues.

———

12 Hours later

As night falls on the reef, the pressure of the plates is reaching a breaking point, finally, the plates slip, and almost immediately, it triggers a massive earthquake, the ground violently rocks back and forth as waves of seismic energy rip through the earth.

Coral reefs may be reinforced with tough, rock-like calcium, but even they have a limit. The rocking of the quake destroys the reef, collapsing huge arches and sending them crashing to the ocean floor, crushing anything underneath.

But it isn’t over yet, the water suddenly starts to recede. When earthquakes happen in the ocean, they can move the water in such a way that it creates a tidal wave, better known as a tsunami. The wave of water sweeps in, destroying everything in its wake.

———

8 hours later

The morning after the tsunami, the reef is almost unrecognizable, shattered pieces of coral litter the ocean floor, along with the corpses of animals thrashed against them by the tsunami.

However, there are some survivors. Trilobites were able to survive by burying themselves in the sand. All is not lost for the reef however, in time, the coral will rebuild itself, creating a coral reef that is bigger and better than the old one.

Next time on Walking with Monsters: We will travel through the late Ordovician, exploring the rise of the sea scorpions.

You know that Walking With Dinosaurs remastered series? Well I’m making a remake of Walking With Monsters!

Now, this does not mean the end of Walking with Dinosaurs, the two series will run concurrently with each other. Also the Walking with Monsters series will also be on AO3 if you wanna read it there, the first chapter is already up there.