Hell Creek Formation, Montana, 68 Million Years Ago

Here in western Montana lies a land populated by some of the most well-known creatures of the Late Cretaceous. Gone is the arid landscape of the state's famous badlands. In its place is a humid, forested wetland, filled with many types of trees including redwoods, ginkgoes, palm trees, bald cypress, and conifers. All these create a canopy made up of many shades of green leaves and various shades of brown tree trunks. The sounds of crickets, frogs, and early birds fill the ambiance of this moist forest. The ground below the trees is made up of mostly brown dirt covered in moss, tree roots, and loose bark. Most of this is shielded by masses of ferns, cycads, quillworts, and horsetails.

Scattered in the vegetation beds is a different kind of plant. The stem is green like everything else, but it is the head that differs. Its top is made up of white outer petals with reddish stems and a yellow core in the middle. These are what we recognize today as Magnolias, one of the earliest flowers. They evolved earlier in the Cretaceous but are already on their way to becoming as common as they are today. For now, they are just part of the diet of one of Hell Creek's larger residents who uses its beak to bite off the Magnolias.

Feasting on the ground vegetation is a Torosaurus, a relative of Triceratops that is as long as two cars and as heavy as a school bus. It's a quadrupedal animal with a short tail, and sprawling, four-toed feet. A blend of greenish-brown dyes it's dry, scaly skin with a creamy, beige underbelly. Just like its more famous cousin, Torosaurus has three keratinous, cream-colored horns adorning its face. One is quite short and bump-like, lying on top of its nose. The other two rest above its eyes, stretching out nearly 4 feet with a slight downward curve. The main way it differs from Triceratops is in its frill which is longer and rectangular with an inward groove at the top. Short, wide bumps adorn the top and sides of this frill with thicker and longer cheek hornets below the bottom. Since this is a male, the frill is stained in bright orange with two black circles outlined in yellow.

The days of this horned vegetarian are primarily spent munching on the plant beds. This process is made easier by the deep, narrow beak at the end of its jaws, allowing it to bite off even the toughest of plant matter. Batteries of teeth in the back of its mouth help to grind up this vegetation, preparing it for easier transport into the Torosaur's stomach for digestion. The chewing sounds of this behemoth are loud and crunching, drowning out its occasional huffs and grunts.

Little does this herbivore know that something lurks not far from him. Hidden behind a taller batch of cycads is a pair of two-legged carnivores, watching with their golden-colored eyes. The Torosaurus stops chewing for a moment, witnessing their three-toed feet step out from the thick vegetation. As they emerge, the peering sunlight makes their identity ever clearer and more visible. They are the most famous carnivores to have ever lived. The apex predators of Cretaceous Montana. The tyrant lizard kings. Tyrannosaurus Rex... juveniles, no more than 10 feet long.

Their snouts, legs, tails, and overall bodies are long and slender, standing no taller than the average 7-year-old human. Both of their famous, two-fingered pairs of hands are pointed toward each other and no longer than their mouths. Above each of their eyes are keratinous bumps that stretch the entire length of their eyelids. Feathers cover the top of their backs, the side of their bellies, and behind their necks.

For the slightly smaller of the two, Scratch, his feathers are reddish brown with short, horizontal streaks of black throughout. His exposed skin is a blend of black and brown, with a yellowish beige on his underbelly and lips. The bumps above his eyes are a brighter shade of reddish-brown, signifying that he's a male. His name comes from a series of scratches and bite marks scarred on his exposed skin.

The slightly larger of the two, Shade, couldn't be more different from his brother. He has far fewer scars with only one thin, barely visible line across his snout. By far the most striking difference is that the colors of his skin and feathers are replaced with various shades of black and dark gray, a byproduct of melanism. As it does with many modern-day predators, this mutation allows him to blend in the shadows more easily.

Paying the T-Rexes no mind, the Torosaurus simply grunts before lowering his face back into the vegetation. The horned herbivore isn't their target for today anyway. Scratch and Shade may have the advantage in numbers, but it will take a much larger predator to take down this full-grown bull. Instead, the brothers have their sights set on a group of much smaller targets.

Further behind the Torosaurus is a herd of 15 Stygimolochs. They belong to the pachycephalosaur family, known for being bipedal herbivores with thick domes on their heads. Stygimolochs are distinguished by four large, gray spikes that grow from the back of their heads up to 4 feet in length. Their gray skin is rough and scaly, covered with dark brown splotches on the body and solid white on their underbellies. The gray skin is much darker on the males along with having bright red on their faces and the top of their 10-inch-thick domes. 10-foot-long adults mainly comprise this herd with a few 9-foot sub-adults. Their sounds are a mix of various snorts, grunts, and trills.

Much like the Torosaurus, the Stygimolochs are preoccupied with feeding on the plentiful plant life of Hell Creek. However, they'll occasionally find an insect like a butterfly to mix up their diet. In their foraging, the herd remains unaware of the Rex brothers creeping through the trees and thicker vegetation around them. Scratch and Shade inch closer and closer, the foliage around them lightly brushing against their skin and feathers. Now, only feet away from the dome heads, the young Tyrannosaurs steadily freeze, waiting for the opportunity to strike.

For Scratch, however, this stillness doesn't last for long. His nose starts to itch and wiggle. He struggles to contain the soft sniffs and snorts he starts to make. Gradually the sounds stop, and the smaller brother becomes silent once again. Suddenly, a loud, hissing sneeze erupts from his jaws and nose. His leg spasms and snaps a twig lying in front of him. One of the Stygimolochs jerks its head up seeing the young rex. The herbivore trills loudly as it dashes away with the rest of the herd.

Swiftly, the brothers follow, trailing only a couple of feet away. Thanks to their long, slender legs, young T-Rexes like Scratch and Shade can easily match the speed of the Stygimolochs. Whether or not their prey would escape is only a matter of how much stamina they have left. As the herd approaches a narrow, muddy river, one 9-foot male starts to lag. Shade runs in ever so close, his jaws opening for the first bite. As the young, dome-head gets further to the back of the herd, the bigger brother aims his head at his prey's left leg.

Scratch abruptly starts to slip on the river mud before falling and crashing into his brother. Shade only grazes the back of the Stygimoloch's leg before his face plants into the muddy ground. By the skin of their teeth, the dome-heads escape into the woods. All the brothers get for their efforts is just a mouth full of mud.

As both young Tyrannosaurs get up off the ground, Shade starts to growl. He turns toward Scratch, his eyes squinting. The smaller brother only lets out a chirp before slowly approaching the bigger one. With no hesitation, Shade bites down on the snout of his brother. Scratch shakes his head all while making muffled chirps and whimpers. Soon, he breaks free only as he's tossed away by his bigger brother. Scratch and Shade then start to make strained squawking sounds at each other.

As Shade opens his mouth ready to squawk, a loud, low-frequency bellow vibrates throughout the woods. It is very deep and raspy, starting with a pulsing boom followed by grumbling. The brothers stop their squawking and stare at each other perplexedly as neither of them could make such a sound, not yet anyway. They start to turn their attention back to the fern clearing as they hear another call, a deep prolonged honk. Quickly, the brothers glance at each other before going back to where they came from.

On their way, they find the source of the honk, a running Torosaurus. Only one thing could scare this living tank, thus the brothers know to jump into a batch of ferns and remain hidden. Soon, the large herbivore stops in his tracks, witnessing an absolute behemoth of a carnivore stepping in front of its path.

Reaching 13 feet tall at the shoulder, this massive predator towers over the 7-foot bull. Its body is over 4 times the length of an average alligator and as heavy as the largest African elephant. It is the one animal bold enough to prey on a Torosaurus, the true king of the Cretaceous, an adult T-Rex.

Gone is the coat of feathers from its younger form. Instead, there's much sparser covering on its back running from behind its skull to just above its hip. Its exposed skin is much like that of Scratch, being mainly brownish black but with lighter gray spots and a darker beige on its underbelly and lips. The keratinous bumps above its eyes are still bright, brownish red, but are larger and more pronounced, signifying it too is a male. His skull has grown to be thicker, his legs more muscular, and his overall body more robust. Although his arms are only as long as a human's, his bulky, 4-foot-long skull with a mouth full of 60 recurved, serrated teeth more than makes up for this.

The giant Tyrannosaur looks down at the Torosaur and lets out a deep, pulsing bellow. In response, the bull turns his skull all about, waving his horn back and forth. The predator stands unphased, only responding with low, growling rumbles.

Soon, a second massive creature emerges from behind the Torosaur, another T-Rex. This one is a female, shown by her slightly shorter length at 40 feet as well as her brow bumps being smaller and colored in light gray. She approaches the bull's right hind leg and clamps her jaws onto it. The Torosaur lets out a loud honk as he turns his head back. It is in this brief window that the male Tyrannosaur clamps his massive mouth around the bull's exposed neck.

Thanks to powerful muscles connecting his jaws, he has the most powerful bite to ever evolve in nature, at up to 10,000 psi. Such a bite can crush even the neck bones of a bull Torosaurus. All this large herbivore can do is let out one last fading honk. It falls lifelessly to the ground as the male T-Rex releases his grip.

Both Tyrannosaurs bite into and start feasting on the dead Torosaur, their chewing, crunching, and gulping loud enough to drown out the frogs and crickets. Steadily, the young brothers march toward the carcass. Shade attempts to bite the body of the bull. Abruptly, a thud occurs, prompting the pair of juveniles to freeze in place. They look up and see the adult male pressing his left foot on the carcass, growling before letting out a loud bellow. Scratch and Shade then walk away as the adults have made it clear that they are not welcome. Both brothers stopped and looked back at the results of the hunt by the adults. They briefly look at each other before venturing deeper into the woods.

***

In a thicker part of Hell Creek's forest, the Stygimoloch herd continues with their feasting. Though the batches of ground vegetation are fewer amongst the dry ground covered in dirt and roots, there is less room for predators to maneuver through. Younger males joust by bashing their skulls into one another, practice for when they fight over dominance and mates later in life. One male struggles in this, no thanks to the pain in his wounded leg.

Suddenly, Scratch jumps out from behind a tree, letting out a series of hissing squawks. In response, the Stygimoloch herd scatters and runs away, all while trilling and snorting. The young rex swiftly follows, focusing on the slower, injured male. Even in his injured state, this Stygimoloch is still able to outrun Scratch, even if just barely.

Soon, Shade jumps out from another tree in front of the injured dome-head. The young male Stygimoloch stops and starts to wave his head, drawing attention to his dome and spikes. The melanistic rex isn't deterred, instead letting out a hissing squawk.

Unbeknownst to the herbivore, Scratch is creeping up behind him, slowly and quietly to keep his footsteps silent. Now only a foot or two away from his prey, the smaller tyrannosaur bites down onto the Stygimoloch's injured leg. The dome-head squeals, jerking his head backward and attempting to kick Scratch away to no avail. Swiftly, Shade grasps his jaws around the Stygimoloch's neck, causing it to squeal even more as its windpipe slowly gets crushed. The young predator has yet to grow the stronger bite of his adult form, thus making this kill slower and requiring more effort. Squealing louder and louder, the dome-head jerks and squirms, only making Shade bite down harder and harder. The struggle decreases as the Stygimoloch's sounds fade.

Through a combination of shock and blood loss, life fades from the herbivore, causing it to plop to the ground as the melanistic carnivore lets go. At last, the brothers' prey is truly theirs, but has not come without a cost. A few of Shade's teeth are missing, with red holes in their place. To a T-Rex, this is only a minor loss. Much like sharks and crocodiles, their teeth constantly grow in and out, no matter what age they are. This will be just some of over hundreds of teeth he'll go through in his lifetime. Soon, they will grow back, closer in size to their adult form.

Shade darts his head toward the dead Stygimoloch's abdomen, biting into and swallowing a chunk of its flesh. Scratch aims his head to the same area, only for his bigger brother to squawk and deter him. Instead, he starts to bite behind the hip of the carcass. These brothers have finally learned to work together in bringing down their prey. However, learning to share will be another matter entirely for these young hunters.