The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.1

The Rise and Fall of the Dinosaurs 6 The King of the Dinosaurs Tyrannosaurus rex Chapter Title art by Todd Marshall THE TRICERATOPS WAS SAFE. It was across the river, separated by impassable rapids from the danger brewing on the opposite bank. But it could see what was about to happen and was powerless to stop it. No more than fifty feet away, on a spike of sand and mud that jutted into the other side of the water, a group of three Edmontosauruses lingered. Their sharp ducklike bills plucked leaves from the flowery shrubs clinging to the shore. Their cheeks—heavy with nourishment—rocked side to side in a chewing motion. The late evening sun shimmered across the currents, and the whistles of birds high in the trees radiated peace and calm. But all was not OK. On the far shore, the Triceratops noticed something the Edmontosaurus herd could not—another creature, hiding in the taller trees at the edge of the jungle where it met the sand bar, its green scaly skin almost perfectly camouflaged. Its eyes gave it away: two bulbous spheres, sparkling with anticipation. They darted from left to right, in split-second intervals, surveying the three unaware plant-munchers. Waiting for the right moment. And then it came, in a burst of violence. The red-eyed, green-skinned monster pounced out of the brush and into the path of the plant-eaters. It was a terrifying sight: the lurking predator was longer than a city bus. It reached forty feet (thirteen meters) long and weighed at least five tons. Fluff stuck out of the scales of its neck and back—a mangy, hairy fuzz. Its tail was long and muscular, its legs stocky, its arms laughably tiny, dangling to the side as it lunged toward the Edmontosaurus pack headfirst, jaws agape. When it opened its mouth, there were about fifty pointy teeth inside, each the size of a railroad spike. They clamped down on the tail of one of the Edmontosauruses, the cacophony of crunching bone and shrieking anguish echoing through the forest. Desperate, the assaulted Edmontosaurus wrestled itself free and waddled off into the trees, its severed tail dangling behind it, carrying a broken tooth from the predator as a battle scar. Would it survive or succumb to its injuries in the hidden depths of the forest? The Triceratops would never know. Annoyed by its failed attack, the beast turned its attention to the smallest of the duckbills, but the youth was racing away into the woods, dodging trunks and bushes at a sprinter’s speed. The bulky carnivore realized it had no hope of catching it and emitted a deep-throated wail in frustration. There was still one Edmontosaurus left, cornered on the sandbar: water on one side, the meat-lusting monster on the other. As the predator turned its head back toward the river, the two of them locked eyes. Escape was impossible, and then the inevitable happened. The head darted forward. Teeth met flesh.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.2

Bones shattered as the neck of the herbivore was ripped apart, blood spilling into the water and mixing with the white foam currents, the broken teeth of the predator raining through the sky as it tore at its victim. Then, from back in the forest, there was a rustling noise. Branches snapped and leaves flew about. The Triceratops watched in awe as four other big-headed, spike-toothed green brutes—nearly identical in size and shape to the first one—bounded onto the riverbank. They were a pack; the attacker was their leader, and now the underlings got to share in its victory. The five hungry creatures snorted and snarled, nipping at each other and biting each other’s faces as they jockeyed for the best cuts of meat. From the comfort of the opposite shore, the Triceratops knew exactly what it was seeing. For it had been there before—it had once escaped the jaws of one of these voracious killers, goring it with one of its horns until the beast released its grip. This feared predator was known to all Triceratops. It was their great rival, the terror that would rush like a ghost from the trees and mow down entire herds. It was Tyrannosaurus rex—the King of the Dinosaurs, the largest predator that has ever lived on land in the 4.5-billion-year history of Earth. T. REX IS a celebrity character—the nightmare haunter—but it was also a real animal. Paleontologists know quite a lot about it: what it looked like, how it moved and breathed and sensed its world, what it ate, how it grew, and why it was able to get so big. In part, that’s because we have a lot of fossils: over fifty skeletons, some nearly complete, more than for almost any other dinosaur. But more than anything, it’s because so many scientists are impulsively drawn to the majesty that is the King, the way so many people are obsessed with movie stars and athletes. When scientists get infatuated with something, we start playing around with every instrument, experiment, or other type of analysis at our disposal. We’ve thrown the whole toolbox at T. rex: CAT scans to look into its brain and sense organs, computer animations to understand its posture and locomotion, engineering software to model how it ate, microscopic study of its bones to see how it grew, and the list goes on. As a result, we know more about this Cretaceous dinosaur than we do about many living animals. What was T. rex like as a living, breathing, feeding, moving, growing animal? Let me indulge you with an unauthorized biography of the King of Dinosaurs. Tyrannosaurus rex skeleton at the American Museum of Natural History in New York. Photo courtesy of the author Let’s start with the vital stats.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.3

It goes without saying, but T. rex was huge: adults were about forty-two feet (thirteen meters) long and weighed in the ballpark of seven or eight tons, based on those equations from a few chapters ago, which calculate body weight from the thickness of the thighbone. These proportions are off the charts for carnivorous dinosaurs. The rulers of the Jurassic—the Butcher Allosaurus, Torvosaurus, and their kin—got up to about thirty-three feet (ten meters) long and a few tons—monsters to be sure, but they had nothing on Rex. After temperature and sea-level changes ushered in the Cretaceous, some of the carcharodontosaurs from Africa and South America got even bigger than their Jurassic predecessors. Giganotosaurus, for example, was about as long as T. rex and may have reached about six tons. But that’s still a good ton or two lighter than Rex, so the King stands alone as the biggest purely meat-eating animal that lived on land during the time of dinosaurs, or indeed at any time in the history of our planet. Show a picture of T. rex to kindergartners and they’ll immediately know what it is. It has a signature style, a unique physique, or in scientific parlance, a distinctive body plan. The head was enormous, perched on a neck short and stout like a bodybuilder’s. Balancing the oversize noggin was a long, tapering tail that stuck out horizontally like a seesaw. Rex stood only on its hind legs, its muscular thighs and calves powering its movements. Like a ballerina, it balanced on the tips of its feet, the arch or sole rarely touching the ground, all of its weight held by its massive three toes. The forelimbs looked useless: puny things with two stubby fingers, comically out of proportion to the rest of the body. And the body itself: not fat like one of the long-necked sauropods, but not the skinny frame of a fast-running Velociraptor either. Its very own body type. The seat of Rex’s power was its head. It was a killing machine, a torture chamber for its prey, and an evil mask all in one. At around five feet long from snout to ear, the skull was nearly the length of an average person. More than fifty knife-sharp teeth made for a sinister smile. There were little nipping teeth at the front of the snout and a row of serrated spikes the size and shape of bananas running along the sides of the upper and lower jaws. Muscles to open and close those jaws bulged out of the back of the head near the bottle-cap-size hole that served as the ear. Each eyeball was the size of a grapefruit. In front of it, but covered in skin, was a massive sinus system that helped to lighten the head, and then big fleshy horns at the tip of the snout.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.4

Small horns protruded in front of and behind each eye, and another stuck downwards from each cheek—gnarly knobs of bone covered in keratin, the same stuff that makes up our fingernails. Imagine this hideous visage as your last memory before the teeth came crushing down, breaking your bones. Many a dinosaur met its end that way. Covering the body—the head, the wee arms, the stocky legs, all the way to tip of the tail—was a thick, scaly hide. In this way, T. rex resembled an overgrown crocodile or an iguana—lizardlike. But there was one key difference: Rex also had feathers sticking out from between its scales. As mentioned in the last chapter, these were not big branching ones like those on a bird wing, but were simpler filaments that looked and felt more like hair, the larger ones stiff like the quills of a porcupine. T. rex certainly couldn’t fly, and neither did its ancestors that first evolved these proto-feathers, way back in the early days of the dinosaurs. No, as we’ll learn later, feathers started out as simple wisps of integument, which creatures like T. rex used to keep warm, and as displays to attract mates and scare off rivals. Paleontologists have yet to find any fossilized feathers on a T. rex skeleton, but we’re confident that it must have had some fluff because primitive tyrannosaurs—Dilong and Yutyrannus, which we met last chapter—have been found coated in hairlike feathers, as have many other types of theropods preserved in those rare conditions that allow soft bits to turn into fossils. That means that the ancestors of T. rex had feathers, so it is highly likely that Rex did too. T. rex lived from about 68 to 66 million years ago, and its dominion was the forest-covered coastal plains and river valleys of western North America. There it lorded over diverse ecosystems that included a bounty of prey species: the horn-faced Triceratops, the duck-billed Edmontosaurus, the tanklike Ankylosaurus, the dome-headed Pachycephalosaurus, and many more. Its only competition for food was from the much smaller dromaeosaurs—raptor dinosaurs à la Velociraptor—which is to say it didn’t have much competition at all. Although several other tyrannosaurs had thrived in these same environments during the preceding 10 to 15 million years, they were not the ancestors of T. rex. Instead, Rex’s closest cousins were Asian species like Tarbosaurus and Zhuchengtyrannus. T. rex, as it turns out, was an immigrant. It got its start in China or Mongolia, hopped across the Bering Land Bridge, journeyed through Alaska and Canada, and made its way down into the heart of what’s now America. When the young Rex arrived at its new home, it found things ripe for the taking. It swept across western North America, an invasive pest that spread all the way from Canada down to New Mexico and Texas, elbowing out all of the other midsize to large predatory dinosaurs so that it alone controlled an entire continent. Then one day it all ended.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.5

T. rex was there when the asteroid fell down from the sky 66 million years ago, putting a violent end to the Cretaceous, exterminating all of the nonflying dinosaurs. That’s a story we’ll get to later. For the time being, only one fact really matters: the King went out on top, cut down at the peak of its power. WHAT FEAST BEFITS the King? We know T. rex was a carnivore of the highest order, a pure meat-eater. It’s one of the simplest inferences that we can make about any dinosaur, and it doesn’t require any fancy experiments or machines to figure out. T. rex had a mouth full of thick, serrated, razor-sharp teeth. Its hands and feet boasted big pointy claws. There’s really only one reason an animal would have these things: they’re weapons, used to procure and process flesh. If your teeth look like knives and your fingers and toes are hooks, then you’re not eating cabbages. For anybody who doubts that, there is plenty of other evidence: bones have been found preserved in the stomach area of tyrannosaur skeletons and in the coprolites (fossilized dung) dropped by tyrannosaurs, and western North America is peppered with skeletons of plant-eating dinosaurs—particularly Triceratops and Edmontosaurus—with bite marks that perfectly match the size and shape of T. rex teeth. Like so many monarchs, Rex was a glutton. It devoured meat. Scientists have predicted how much food an adult T. rex would need to survive, based on the food intake of living predators scaled up to an animal of Rex’s size. The estimates are nauseating. If T. rex had the metabolism of a reptile, then it would have required about 12 pounds (5.5 kilograms) of Triceratops chops per day. But that’s very likely a vast underestimate, because as we’ll see later, dinosaurs were much more birdlike than reptilian in their behaviors and physiology, and they (or at least many of them) may have even been warm-blooded like us. If that was the case, then Rex needed to gobble up some 250 pounds (about 111 kilograms) of grub each and every day. That’s many tens of thousands of calories, maybe even hundreds of thousands, depending on how fatty the King liked its steak. It’s roughly the same amount of food eaten by three or four large male lions, some of the most energetic, and hungriest, modern carnivores. Maybe you’ve heard the rumor that T. rex liked its meat dead and rotten, that Rex was a scavenger, a seven-ton carcass collector too slow, too stupid, or too big to hunt for its own fresh food. This accusation seems to make the rounds every few years, one of those stories that science reporters can’t get enough of. Don’t believe it. It defies common sense that an agile and energetic animal with a knife-toothed head nearly the size of a Smart car wouldn’t use its well-endowed anatomy to take down prey but would just walk around picking up leftovers.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.6

It also runs against what we know about modern carnivores: very few meat-eaters are pure scavengers, and the outliers that do it well—vultures, for instance—are fliers that can survey wide areas from above and swoop down whenever they see (or smell) a decaying body. Most carnivores, on the other hand, actively hunt but also scavenge whenever they have the chance. After all, who turns down a free meal? That’s true of lions, leopards, wolves, even hyenas, which are not the pure scavengers of legend but actually earn much of their food through the chase. Like these animals, T. rex was probably both a hunter and an opportunistic scavenger. Still doubt that Rex went out and got its own food? There’s fossil evidence that proves T. rex hunted, at least part of the time. Many of those Triceratops and Edmontosaurus bones pockmarked with T. rex tooth impressions show signs of healing and regrowth, so they must have been attacked while alive but survived. The most provocative of these specimens is a set of two fused Edmontosaurus tailbones with a T. rex tooth stuck between them, enveloped by the gnarly mass of scar tissue that merged the two bones together as they healed. The poor duck-billed dinosaur was viciously attacked by a tyrannosaur and left with a terrible injury, but it kept the predator’s tooth as a trophy from its near-death experience. Many of Rex’s bite marks are peculiar. Most theropods left simple feeding traces on the bones of their prey: long, parallel, shallow scratches, a sign that the teeth were just barely kissing the bone. That’s not surprising, because even though dinosaurs could replace their teeth throughout life (unlike us), no predator would want to break its chompers every time it ate. T. rex was different, though. Its bite marks are more complex: they start with a deep circular puncture, like a bullet hole, which grades into an elongate furrow. This is a sign that Rex bit deeply into its victim, often right through the bones, and then ripped back. Paleontologists have come up with a special term for this style of eating: puncture-pull feeding. During the puncture phase of its bite, Rex clamped down hard enough to literally break through the bones of its prey. This is why the fossilized dung heaps left by T. rex are chock full of bony chunks. Bone crunching is not normal—some mammals, like hyenas, do it, but most modern reptiles do not. As far we know, big tyrannosaurs like T. rex were the only dinosaurs capable of it. It was one of the powers that made the King an ultimate killing machine. How was T. rex able to do it? For starters, its teeth were perfectly adapted. The thick, peglike teeth were strong enough that they wouldn’t easily break when they hit bone.


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Next, consider the power behind those teeth: T. rex’s jaw muscles were massive, bulging mounds of sinew that provided enough energy to shatter the limbs, backs, and necks of Triceratopses, Edmontosauruses, and other prey. We can tell that Rex had some of the largest and most powerful jaw muscles of any dinosaur, based on the very broad and deep gullies on the skull bones where the muscles attached. Experiments can simulate the actions of these jaw muscles. One of my colleagues, Greg Erickson of Florida State University, designed a particularly clever experiment in the mid-1990s, right after he finished graduate school. Greg is one of my favorite people to hang around with—he talks with the cadence of high school jock and often looks the part in his worn baseball cap, cold beer in hand. A few years back, Greg was a regular talking head on a cable TV program about weird animal incidents—alligators crawling through sewers and invading trailer parks, that kind of thing. As much fun as he is, I admire Greg deeply as a scientist, because he brings a different approach to paleontology—experimental, quantitative, rigorously grounded in comparisons to modern animals. Greg spends a lot of time with engineers, and one day they came up with a crazy idea: they would rig up a laboratory version of T. rex and determine how strong its bite was. They started with a Triceratops pelvis with a half-inch-deep puncture left by a Rex, and then asked a simple question: how much force would it take to make an indentation this deep? They couldn’t take a real T. rex and make it bite into a real Triceratops, but they found a way to simulate it by making a bronze and aluminum cast of a T. rex tooth, putting it into a hydraulic loading machine, and smashing it into the pelvis of a cow, which is very similar in shape and structure to the Triceratops bone. They pushed and pushed the tooth until it made a half-inch-deep hole, and then used their instruments to read out how much force it required: 13,400 newtons, equivalent to about 3,000 pounds. That’s a staggering number—about the weight of an old-school pickup truck. By comparison, humans exert a maximum force of about 175 pounds with our rear teeth, and African lions bite at about 940 pounds. The only modern land animals that come close to T. rex are alligators, which also bite at around 3,000 pounds. However, we need to remember that the 3,000-pound figure for T. rex is for only a single tooth—imagine how much power a mouth full of these railroad spikes would have delivered! And because it’s a measure of the force required to make one observed fossil bite mark, it’s likely that this is an underestimate of the maximal biting power. Rex probably had the strongest bite of any land animal that ever lived. It could crunch bones with ease and would have been strong enough to bite through a car.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.8

All of that strength came from the jaw muscles; they were the engine that powered the teeth to deliver the bone-breaking bite. But that’s not the entire story. If the muscles delivered enough force to bust the bones of prey, they could have also broken the skull bones of the T. rex itself. Basic physics: every action has an equal and opposite reaction. So it wasn’t enough for T. rex to have massive teeth and huge jaw muscles—it also needed a skull that could withstand the tremendous stresses that occurred each time it snapped its jaws shut. To figure out how, we needed to turn back to the engineers and to another paleontologist who has crossed over into the realm of hard-core numbers science. Emily Rayfield’s lab at the University of Bristol in England is a big bright room with a row of computers, its large windows and breezy open plan like something out of Silicon Valley. The shelves are lined with manuals for various software packages, but there’s nary a fossil in sight. Emily doesn’t often collect fossils; she’s not that kind of paleontologist. Instead, she builds computer models of fossils—say, the skull of T. rex—and uses a technique called finite element analysis (FEA) to study how they would have behaved in a mechanical sense. FEA was developed by engineers and calculates the stress and strain distributions in a digital model of a structure when it is subjected to various simulated loads. In plain English, it’s a way to predict what will happen to something when some kind of force is applied to it. This is very useful for engineers. Before a construction crew starts building a bridge, let’s say, the engineers better be pretty damn sure that the bridge isn’t going to collapse when heavy cars start driving over it. To check, they can build a digital model of the bridge and use the computer to imitate the stresses from real cars to see how the bridge reacts. Does it absorb the weight and force of the cars easily, or does it start to crack under pressure? If it does start to crack, the computer can identify the weak points and the engineers can go back to the plans for the actual bridge to make the necessary fixes. Emily does the same thing with dinosaurs, and T. rex has been one of her favorite muses. She built a digital model of Rex’s skull based on CAT scans of a well-preserved fossil, and then used the FEA program to simulate the forces of a bone-crunching bite and analyze how the skull reacted. The verdict: T. rex had a remarkably strong skull that was optimized to endure the extreme pushing and pulling forces of its three-thousand-pound-per-tooth chomp. It was built like an airplane fuselage: the individual bones tightly sutured together so that they wouldn’t come apart when the stress hit. The nasal bones above the snout were fused together into a long, vaulted tube, which acted as a stress sink.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.9

Thick bars of bone around the eye provided strength and rigidity, and the robust lower jaw was almost circular in cross section so that it could withstand high pressures from all directions. None of these things are present in other theropods, which had daintier skulls with looser connections among the various bones. The skull of Tyrannosaurus rex. Courtesy of Larry Witmer. The brain cavity (upper right-hand corner) and sinuses inside the skull of a Tyrannosaurus rex, revealed by CAT scans. Courtesy of Larry Witmer. That’s the final piece of the puzzle, the last component in the tool kit that allowed T. rex to bite so strongly that it punctured, and then pulled through, the bones of its supper. Thick peg-like teeth, huge jaw muscles, and a rigidly constructed skull: that was the winning combination. Without any of these things, T. rex would have been a normal theropod, slicing and dicing its prey with care. That’s how the other big boys did it—Allosaurus, Torvosaurus, and the carcharodontosaurs—because they didn’t have the arsenal necessary for bone-crunching. Once again, the King stands alone. T. REX WAS able to gnash through most anything that it wanted to eat, whether it was splurging on a forty-foot-long Edmontosaurus or snacking on smaller contemporaries like the donkey-size ornithischian Thescelosaurus. But how did it capture its food? Not, as it turns out, with exceptional speed. T. rex was a special dinosaur in many ways, but one thing it could not do is move very fast. There’s a famous scene in Jurassic Park where the bloodthirsty T. rex, convulsed by its insatiable appetite for human flesh, chases down a jeep driving at highway speeds. Don’t believe the movie magic—the real T. rex likely would have been left in the dust once the jeep got up to third gear. It’s not that Rex was a plodding slouch that waddled through the forest. Far from it—T. rex was agile and energetic, and it moved with purpose, its head and tail balancing each other as it tiptoed through the trees, stalking its prey. But its maximum speed was probably in the ballpark of ten to twenty-five miles per hour. That’s faster than we can run, but it’s not as quick as a racehorse or, certainly, a car on the open road. Once again, it’s high-tech computer modeling that has allowed paleontologists to study how T. rex moved. This work was pioneered in the early 2000s by John Hutchinson, an American transplant to England who is now a professor at the Royal Veterinary College near London. He spends his days working with animals: monitoring the livestock on his university’s research campus, making elephants run across scales to study their posture and locomotion, dissecting ostriches and giraffes and other exotic creatures. John chronicles his adventures on his popular blog, the wonderfully but somewhat disturbingly titled What’s in John’s Freezer?


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.10

He also pops up frequently as a talking head on television documentaries, often adorned in his favorite purple shirt, which somehow doesn’t crack the cameras with its glare. Like Greg Erickson, John is a scientist whom I’ve long admired because of his unique angle on studying dinosaurs. For John, the present is very much the key to the past: find out as much as we can about the anatomy and behaviors of today’s animals, and that will help us understand dinosaurs. If you visit John’s lab, he really does have freezers stocked with the frozen cadavers of animals of all shapes and sizes, from all over the world. Odds are, one or two of them will be out thawing, getting ready for the dissection table. But there is a more sterile side to John’s lab: the computers, which he uses to make digital models of dinosaurs, like those we saw in chapter 3 that we made to predict the weight and posture of long-necked sauropods. He starts with a three-dimensional model of a skeleton, captured through CAT scans, laser surface scans, or the photogrammetry method we learned about earlier. Then he uses his knowledge of modern animals to flesh it out: to add muscles (whose sizes and positions are based on the attachment sites visible on the fossil bones) and other soft tissues, wrap it up in skin, and position it in realistic postures. The computer does its magic, putting the model through all sorts of gymnastics routines, and calculates how fast the real animal was likely able to move. John’s modeling provides us with the range of ten to twenty-five miles per hour that I cited for T. rex’s speed. The computer models also make clear that Rex would have needed absurdly large leg muscles to run as fast as a horse: more than 85 percent of its total body mass in its thighs alone, which is obviously impossible. T. rex was simply too big to run exceptionally fast. Its sheer size also conferred another liability: the Tyrant King couldn’t turn very quickly, or otherwise it would topple over like a truck taking a corner too sharply. Thus, the reality is, Spielberg had it wrong, T. rex was no sprinter, and it would have ambushed its prey with a quick strike rather than chasing it down like a cheetah. Ambushing prey can take a lot of energy—in bursts. Thankfully, T. rex had another trick up its sleeve, or more precisely, deep inside its chest. Remember those hyperefficient lungs of sauropods, which allowed them to reach such enormous sizes? T. rex had the same lungs. They are the lungs of today’s birds: rigid bellows anchored to the backbone, able to extract oxygen when the animal breaths in and also when it breathes out. They’re different from our lungs, which can take in oxygen only during inhalation, then spew out carbon dioxide during exhalation. They are a stunning feat of biological engineering.


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When today’s birds—and also T. rex—breathe in, oxygen-rich air courses through the lungs as you would expect. However, some of the inhaled air doesn’t go through the lungs right away but is shunted into a system of sacs connected to the lung. There it waits, until it is released when the animal exhales, passing through the lungs and delivering its oxygen-rich hit even as carbon dioxide waste is being expelled. Birds get twice the bang for the buck, a continuous supply of energy-sustaining oxygen. If you’ve ever wondered how some birds can fly at tens of thousands of feet, in rarefied air where we would have a hard time breathing (just ask anyone who has experienced the oxygen masks coming down midflight), their lungs are their secret weapon. Paleontologists have yet to find a fossilized T. rex lung and probably never will. The thin tissues are too delicate to fossilize. But we know that Rex had a birdlike, ultra-efficient lung, because this kind of breathing system leaves impressions on the bones, which do fossilize. It all has to do with the air sacs, the air-storage compartments integral to the bird-style lung. These sacs are akin to balloons: they are soft, thin-walled, compliant bags that inflate and deflate during the ventilation cycle. Many air sacs are connected to the lung, nestled in between the many other organs of the chest, including the trachea and esophagus, the heart, the stomach, and intestines. Sometimes they run out of room and start wiggling their way into the only space still available: the bones themselves. As they do so, they invade the bone through large, smooth-walled holes and then expand into chambers once inside. These signatures are easy to identify on fossils. We see them on the backbones of T. rex, along with many other dinosaurs, including, as we learned about earlier, the humongous sauropods. We never see these things on mammals, or lizards, or frogs, or fish, or any other types of animals—only in modern birds and extinct dinosaurs and a few very close relatives, a telltale fingerprint of their unique lungs. The drama of a T. rex ambush is coming into focus. The lungs delivered the energy, which was then transferred to the leg muscles, which propelled the Rex forward with a burst of speed to lunge at its startled victim. And then what happened? Just imagine T. rex as a giant land shark. Like a Great White, all of the action was with its head. Rex led with its noggin and used its clamp-strong jaws to grab its dinner, subdue it, kill it, and crunch through its flesh and guts and bones before swallowing. T. rex simply had to hunt headfirst, because its arms were pitifully tiny. The King evolved from smaller tyrannosaur ancestors, like Guanlong and Dilong, that used their much longer arms to grab their prey.


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But during the course of tyrannosaur evolution, the head got bigger, the arms got smaller, and the skull gradually took over all of the hunting functions that the arms used to perform. Why, then, did T. rex still have arms? Why didn’t it lose them completely, the way whales ditched their no-longer-necessary hindlegs when they evolved from land mammals that colonized the water? That mystery has captivated scientists for a long time, and it’s kept cartoonists and comedians supplied with an endless source of material for bad puns. As it turns out, those little arms—as silly as they may look—were not useless. Although short, they were stocky and muscular, and they served a purpose. Sara Burch figured it out. Sara and I both trained in Paul Sereno’s lab at the University of Chicago, where we became friends, but our paths diverged afterward: I went down the route of studying genealogy and evolution, and Sara became enthralled with bones and muscles. She did her PhD in an anatomy department, where she dissected a zoo’s worth of animals, and has since carved out a career that is common for paleontologists: teaching human anatomy to medical students. Sara knows more about the anatomical structure of dinosaurs than almost anyone alive—how their bones connected to each other, what kind of muscles they had. She reconstructed the forearm muscles of T. rex and many other theropods, determining which muscles were present, and how big they were, from the preserved attachment sites on the bones, helped along by comparisons to modern reptiles and birds for guidance. Rex’s seemingly sad arms actually turned out to have powerful shoulder extensors and elbow flexors—exactly those muscles needed to hold on to something that is trying to pull away, to keep it close to the chest. It seems that T. rex used its short but strong arms to hold down struggling prey while the jaws did their bone-crunching thing. The arms were accessories to murder. Now there’s one final twist in the story of how T. rex hunted. We increasingly believe that Rex didn’t go on the prowl alone; it traveled in packs. The evidence comes from a Canadian fossil site located between Edmonton and Calgary, in what is now Dry Island Buffalo Jump Provincial Park. It was discovered back in 1910 by none other than Barnum Brown, who just a few years earlier found the first T. rex skeleton in Montana. Brown was traveling through the heart of the Canadian prairies, floating down the Red Deer River on a boat and dropping anchor wherever he saw dinosaur bones sticking out of the riverbank. When he came to Dry Island, he noticed a number of bones from a slightly older cousin of T. rex called Albertosaurus, one of the North American apex predators right before Rex migrated over from Asia. He had time to collect only a small sample before heading back to New York.


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Those bones languished deep in the vaults of the American Museum for decades, until Phil Currie—Canada’s leading dinosaur hunter (and one of the nicest guys you’ll ever meet) — took notice of them in the 1990s. He retraced Brown’s steps, relocated the site, and began excavating. Over the next decade, his team collected more than a thousand bones, which belong to at least a dozen individuals, ranging from youngsters to adults, all of them Albertosaurus. There’s really only one way numerous individuals of the same species can be preserved together: they must have lived and died together. A few years later, Phil’s crew found a similar mass graveyard in Mongolia, packed with several Tarbosauruses, the very closest Asian cousin of T. rex. Albertosaurus and Tarbosaurus were evidently pack animals, and we reckon that Rex itself was as well. If a seven-ton, bone-crunching, ambush predator isn’t scary enough on its own, then just imagine a pack of them working together. Sweet dreams! LET’S GET INTO the King’s head. What did it think? How did it sense its world? How did it locate its prey? These are, of course, very difficult questions to answer. Even with modern living animals, it’s almost impossible to put ourselves in their feet, or paws, or paddles and feel what their world is like. But we can study their brains and sense organs and start to put together a picture. With dinosaurs, however, we are usually out of luck: the brains, eyes, nerves, and tissues associated with the ears and nose are soft and decay easily, meaning they rarely make it through the rigors of fossilization. What can we do? Technology, yet again, makes the impossible possible. The brains, ears, noses, and eyes of dinosaurs may be long gone, but these organs occupied spaces in the bones. The brain cavity, the eye socket, and so on. We can study these spaces to get a sense of the original sense organs that filled them, but there is another problem: many of these spaces are inside the bones, not observable from the outside. That’s where the technology comes in: we can use CAT scans (also known by the shorter abbreviation of CT) to visualize the inside of dinosaur bones. CAT scans are nothing more than high-powered X-rays. That’s why they’re popular in medicine: if you feel a pain in your gut or a creak in your bones, your doctor will probably stick you in a CAT scanner to see what’s going on inside your body without having to cut you open. Ditto with dinosaurs. We can use the X-rays to take an array of internal images, which we can then stitch together into three-dimensional models using various software packages. This procedure has become practically routine in paleontology, such that many labs—including my own in Edinburgh—have a CAT scanner onsite.


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Ours was hand-built by one of my colleagues, Ian Butler, a geochemist by training who now finds himself scanning fossil after fossil, each one leading him deeper into the addiction that is paleontology. Ian Butler CAT-scanning the skull of the primitive tyrannosaur Timurlengia at the University of Edinburgh. Photo courtesy of the author A CAT scan reconstruction of the brain, inner ear, and associated nerves and blood vessels of Tyrannosaurus rex. Courtesy of Larry Witmer. Ian and I are newcomers to the fossil-scanning game. We’re following in the footsteps of a few giants in the field: Larry Witmer of Ohio University, Chris Brochu of the University of Iowa, and the wife-and-husband team of Amy Balanoff and Gabe Bever, who started at the University of Texas, moved on to the American Museum in New York (where I met them when I was a PhD student), and are now ensconced at Johns Hopkins University in Baltimore. Balanoff and Bever are virtuosos who can read CAT scans the way a linguist deciphers ancient manuscripts. In the grayscale splotches of the X-rays, they can make out the internal structures that powered the intelligence and sensory prowess of long-dead dinosaurs. Tyrannosaurs like T. rex have been some of their favorite subjects—their favorite patients, if you will, whose behaviors and cognitive abilities are mysteries to be diagnosed. The scans tell us quite a bit about our patient. First off, Rex had a distinctive brain. It didn’t look anything like our brain but was more of a long tube with a slight kink at its back, surrounded by an extensive network of sinuses. It’s also a relatively large brain, at least for a dinosaur, which hints that T. rex was fairly intelligent. Now, measuring intelligence is riddled with uncertainties, even for humans: just think of all of the IQ tests, exams, SAT scores, and other things that we use to try to assess how smart people are. However, there is a straightforward measure that scientists use to roughly compare the intelligence of different animals. It’s called the encephalization quotient (EQ). It’s basically a measure of the relative size of the brain compared to the size of the body (because, after all, bigger animals have bigger brains simply because of their body size: elephants have bigger brains than we do but are not more intelligent). The largest tyrannosaurs like T. rex had an EQ in the range of 2.0 to 2.4. By comparison, our EQ is about 7.5, dolphins come in around 4.0 to 4.5, chimps at about 2.2 to 2.5, dogs and cats are in the 1.0 to 1.2 range, and mice and rats languish around 0.5. Based on these numbers, we can say that Rex was roughly as smart as a chimp and more intelligent than dogs and cats. That’s a whole lot smarter than the dinosaurs of stereotype. One part of the tyrannosaur brain was particularly enlarged: the olfactory bulbs.


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These are the lobes at the front of the brain that control the sense of smell. The two bulbs were each a little larger than a golf ball, much bigger in absolute size than in any other theropods. Of course, T. rex was one of the biggest theropods, so maybe it had whopping olfactory lobes simply by virtue of its extreme bulk. What is needed, then, is a relative measure of olfactory bulb size. My friend Darla Zelenitsky of the University of Calgary did just that. She compiled CAT scans of numerous theropods, calculated the size of their olfactory bulbs, and normalized them by dividing by body size. Even after all of this, she still found the big tyrannosaurs to be extreme outliers: they, along with the raptor dinosaurs, had proportionally enormous olfactory bulbs, and thus a sharp sense of smell, compared to other meat-eating dinosaurs. It wasn’t only the nose. Other senses were heightened as well. The CAT scans allow us to see inside Rex’s inner ear: the pretzel-shaped network of tubes that control both hearing and balance. The semicircular canals at the top of the inner ear—which make the pretzel shape—were long and loopy. As we know from comparisons to modern animals, this means that T. rex was agile and capable of highly coordinated head and eye movements. Sticking downward from the pretzel is the cochlea, the part of the inner ear that regulates hearing. In T. rex the cochlea was elongated, more than in most other dinosaurs. There is a tight relationship in living animals: the longer the cochlea, the better sensitivity to lower-frequency sounds. In other words, Rex also had a keen sense of hearing. Vision, too: the huge eyeballs of T. rex faced partially to the side and partially to the front, meaning that they were capable of binocular vision. The King could see in three dimensions and perceive depth, just like us. There’s another scene in Jurassic Park where the freaked-out humans are told to stay still, because if they don’t move, then the T. rex can’t see them. Nonsense—because it could sense depth, a real Rex would have made an easy meal out of those sad, misinformed people. Thus it wasn’t all brute strength. T. rex had brawn all right, but it also had brains. High intelligence, world-class sense of smell, keen hearing and vision. Add these things to the armory: they’re what Rex used to target its victims, to choose which poor dinosaurs would have to die. WHEN I ENVISION T. rex as a real animal, what most amazes me is that it would have started life as a tiny hatchling. All dinosaurs, as far as we know, hatched from eggs. We have yet to find any T. rex eggs, but we do have eggs and nests of many closely related theropods. Most of these dinosaurs seemed to guard their nests and provide at least a bit of care for their young.


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Without some parental love, the baby dinosaurs would have been hopeless, because they were tiny: no dinosaur eggs that we know of are larger than a basketball, so even the mightiest species like T. rex would have been, at most, the size of a pigeon when they entered the world. Back when my parents were learning about dinosaurs in school, the assumption was that T. rex and kin grew like iguanas: they kept growing throughout their life, gradually getting bigger and bigger and bigger. Rex was able to get so large because it lived for a long time: after about a century, it would reach its final size of forty-two feet and seven tons, then finally saunter off and die. This type of thinking even percolated into the dinosaur books I read as a child, but like many once cherished notions about dinosaurs, it turns out to be false. Dinosaurs like T. rex grew rapidly, a lot more like birds than lizards. The evidence is buried deep inside the bones of dinosaurs, and paleontologists like Greg Erickson found a way to tease it out. Bones are not static rods and blobs stuck in our bodies; no, they’re dynamic, growing, living tissues that repair and remodel themselves constantly. This is why your bones heal if you break them. As most bones grow, they get wider in all directions, expanding outward from the center, but usually bones grow rapidly only during certain parts of the year: the summer or the wet season, when food is plentiful. Growth slows down during the winter or dry season. If you cut open a bone, you can see a record of each time growth transitions from rapid to slow: a ring. That’s right—just like trees, bones have rings inside, and because that summer-to-winter switch happens once a year, that means one ring is laid down each year. By counting the rings you can tell how old a dinosaur was when it died. Tyrannosaurus rex skeleton on display at the Royal Tyrrell Museum in Alberta, Canada. Photo courtesy of the author Greg got permission to cut open the bones of several different T. rex skeletons, along with many other close tyrannosaur relatives like Albertosaurus and Gorgosaurus. Shockingly, not a single bone had more than thirty growth rings. That means tyrannosaurs matured, reached adult size, and died within three decades. Big dinosaurs like T. rex didn’t grow slowly for many decades (or centuries) but must have reached their huge sizes by growing rapidly for a much shorter period of time. But how quickly? To figure it out, Greg constructed growth curves: he plotted the age of each skeleton, determined from the number of bone rings against its body size, calculated from those equations we learned about earlier that estimate weight based on limb dimensions. This allowed Greg to compute how quickly T. rex grew each year.


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The number is almost too big to comprehend: during its teenage years, from about ages ten to twenty, Rex put on about 1,700 pounds (760 kilograms) per year. That’s close to 5 pounds per day! No wonder T. rex had to eat so much—all of that Edmontosaurus and Triceratops flesh fired the insane teenage growth spurt that turned a kitty-size hatchling into the King of the Dinosaurs. You could call T. rex the James Dean of dinosaurs: it lived fast and died young. And all of that hard living put a tremendous strain on its body. The skeleton had to endure the daily addition of five pounds during the spurt years. Somehow the body had to morph from wee hatchling to monster, so it comes as no surprise that the skeleton of T. rex changed dramatically as it matured. As youngsters, they were sleek cheetahs, as teenagers gangly looking sprinters, and as adults pure-blooded terrors longer and heavier than a bus. The younger ones probably ran a lot faster than the adults and maybe could have chased down their prey, whereas the silverbacks were so huge that they could only ambush and relied much more on their strength than their speed. What’s particularly frightening is that juveniles and adults seemed to live together in packs, meaning they may have hunted in teams, complementing each other’s skills to make life hell on their prey. One of my dearest paleontologist friends has made a career studying how T. rex changed as it grew. He’s a Canadian named Thomas Carr, now a professor at Wisconsin’s Carthage College. You can spot Thomas from a mile away. He has the fashion sense of a 1970s preacher and some of the mannerisms of Sheldon Cooper from The Big Bang Theory. Thomas always wears black velvet suits, usually with a black or dark red shirt underneath. He has long bushy sideburns and a mop of light hair. A silver skull ring adorns his hand. He’s easily consumed by things and has a long-running obsession with absinthe and the Doors. That and tyrannosaurs: he’ll talk a lot about T. rex, because it’s his favorite subject of all. Ever since he was young, he wanted to study the Tyrant King, and he eventually wrote a PhD dissertation on how the skull of T. rex changed as it matured. It was over 1,270 pages long; meticulous as Thomas always is, it’s one of his shorter scholarly works. Bone by bone, Thomas has chronicled the metamorphosis of Tyrannosaurus rex. Almost the entire head was reshaped as it went from boy to man, girl to woman. The skull started out long and low, with a stretched-out snout, thin teeth, and shallow depressions for jaw muscles. Throughout the teenage years, it got bigger, deeper, and stronger. The sutures between bones locked more tightly together, the jaw-muscle depressions became much deeper, and the teeth turned into bone-shattering pegs.


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The juveniles weren’t capable of puncture-pull feeding; that only became possible in adulthood, around the same time that Rex switched from a speedster to a slower ambusher. There were other changes too: the sinuses within the skull expanded, probably to help lighten the ever heavier head, and the little horns on the eyes and cheeks became larger and more prominent, the tiny bumps becoming gaudy display ornaments to attract mates when those teenage hormones kicked in. It was quite the transformation. After all of those meals, the decade of exponential growth, the complete refiguring of the skull, the loss of the ability to run fast but the acquisition of puncture-pull biting, the Rex was all man, all woman, and ready to claim its throne. AND THERE YOU have it, a glimpse into the life and times of the most famous dinosaur in history. T. rex bit so hard it could crunch through the bones of its prey, it was so bulky that it couldn’t run fast as an adult, it grew so fast as a teenager that it put on five pounds a day for a decade, it had a big brain and sharp senses, it hung around in packs, and it was even covered in feathers. Maybe it’s not the biography you were expecting. And there’s the rub. Everything we have learned about T. rex tells us that it, and dinosaurs more generally, were incredible feats of evolution, well adapted to their environments, the rulers of their time. Far from being failures, they were evolutionary success stories. They were also remarkably similar to animals of today, particularly birds—Rex had feathers, grew rapidly, and even breathed like a bird. Dinosaurs were not alien creatures. No, they were real animals that had to do what all animals do: grow, eat, move, and reproduce. And none of them did it better than T. rex, the one true King.


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The Rise and Fall of the Dinosaurs 7 Dinosaurs at the Top of Their Game Triceratops Chapter Title art by Todd Marshall AS TERRIFYING AS IT WAS, T. rex was not a global supervillain. Its dominion was North America—western North America, to be more precise. No Asian, European, or South American dinosaurs lived in fear of T. rex. In fact, they never would have met one. During the latest Cretaceous—the last throes of dinosaur evolution, about 84 to 66 million years ago, when T. rex and its jumbo-size tyrannosaur cousins topped the food chain—the geographical harmony of Pangea was a distant memory. By then, the supercontinent had long ago fractured into pieces, each chunk drifting apart from the others slowly over the Jurassic and Early to middle part of the Cretaceous, the gaps in between the new shards of land filled by oceans. When T. rex took its crown, just a couple million years before the Age of Dinosaurs ended in a bang, the map was more or less as it is today. North of the equator there were two big landmasses: North America and Asia, with essentially their modern shapes. They ever so slightly kissed each other near the North Pole, but otherwise were separated by a wide Pacific Ocean. There was an Atlantic Ocean, too, on the other side of North America, which encircled a series of islands that corresponded to modern-day Europe. Sea level was so high during the latest Cretaceous—the result of a hothouse world where very little, if any, water was locked up in polar ice caps—that most of low-lying Europe was flooded. Only a constellation of random morsels—the higher parts of Europe—poked up from the waves. High sea level also pushed water farther inland, so that warm subtropical seas lapped far onto both North America and Asia. The North American seaway extended all the way from the Gulf of Mexico to the Arctic. In effect, it bisected the continent into an eastern slice called Appalachia and a western microcontinent called Laramidia, the hunting grounds of T. rex. It was a similar situation in the south. The yin-and-yang puzzle pieces of South America and Africa had just recently detached, a narrow corridor of the South Atlantic nestled between. Antarctica sat at the bottom of the world, balanced on the South Pole. Off to its north was Australia, a bit more crescent-shaped than it is today. Fingers of crust kept Antarctica in contact with both Australia and South America, but these were tenuous, liable to be swamped any time sea level crept up slightly. During those high-water stands, just as in the north, seas extended far inland onto the southern continents, drowning much of northern Africa and southern South America. What is now the Sahara would have been waterlogged. However, during those times when the seas receded a little bit, an archipelago provided a route between Africa and Europe—a highway, albeit a fleeting and treacherous one, between north and south.


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A few hundred miles off the east coast of Africa was a triangular wedge, an island continent. This was India, the only large piece of land in the latest Cretaceous that would look out of place to us today. India began its life as a sliver of ancient Gondwana—the big mass of southern lands that separated from the north when Pangea began to split—wedged in between what would become Africa and Antarctica. It severed all ties with its neighbors some time during the early part of the Cretaceous and began a race northward, moving at more than six inches (fifteen centimeters) per year. Most continents, by contrast, drift at a much slower pace, about the speed that our fingernails grow. This brought India to the middle part of the proto–Indian Ocean, a bit south of the Horn of Africa, in the latest Cretaceous. Another 10 million years or so and it would complete its journey, colliding with Asia to form the Himalayas, but by then the dinosaurs were long gone. In between these pieces of land were the oceans—a domain dinosaurs were never able to conquer. The warm waters of the Cretaceous, as during the Jurassic and Triassic beforehand, were the hunting grounds of various types of giant reptiles: plesiosaurs with long noodle-shaped necks, pliosaurs with enormous heads and paddlelike flippers, streamlined and finned creatures called ichthyosaurs that looked like reptilian versions of dolphins, and many others. They dined on each other and on fish and sharks (most of which were much smaller than today’s species), which in turn fed on tiny shelled plankton that choked the ocean currents. None of these reptiles were dinosaurs—even though they are often mistaken for dinosaurs in popular books and movies, they were merely distant reptilian cousins. For whatever reason—and we don’t yet know the answer—no dinosaurs were able to do what whales did: start on the land, change their bodies into swimming machines, and make a living in the water. They were stuck on the land, one of the few liabilities they were never able to overcome. In the latest Cretaceous, this meant that they had to deal with a disjointed world. The land was divided into different kingdoms, fragments of dry ground separated by those reptile-infested seas, their dinosaurs isolated from each other. And that includes T. rex. The King may have been able to easily subjugate the dinosaurs of Europe or India or South America, but it never got the chance. It was restricted to western North America. This was good news for other dinosaurs, especially the plant-eaters, but it also gave other types of meat-eaters the opportunity to seize their own kingdoms, and various groups of carnivores did just that, the story a little bit different on each of the Cretaceous continents. Each landmass had a unique suite of dinosaurs—its own megapredators, second-tier hunters, scavengers, big and small herbivores, and omnivores.


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Provinciality extended to other species as well: there were distinct types of crocodiles, turtles, lizards, frogs, and fishes on the various parcels of land, and of course, different types of plants too. In this way, isolation bred diversification. So it was that the latest Cretaceous—this world of such geographical and ecological complexity, with different ecosystems stranded on different continents—was the heyday of the dinosaurs. It was their time of greatest diversity, the apogee of their success. There were more species than ever before, from pint-size ones to giants, eating all kinds of foods, endowed with a spectacular variety of crests, horns, spikes, feathers, claws, and teeth. Dinosaurs at the top of their game, doing as well or better than they had ever done, still in control more than 150 million years after their earliest ancestors were born on Pangea. TO FIND THE best fossils of latest Cretaceous dinosaurs—including bones of T. rex itself—you have to go to hell—or rather, the badlands surrounding Hell Creek, a once trickling tributary of the Missouri River that is now a flooded arm of a reservoir in northeastern Montana. It’s a place of stifling humidity and mosquito swarms, with rare breezes and little shade. Just rock bluffs that stretch to the horizon in all directions, radiating heat like a sauna. Barnum Brown was one of the first explorers to visit Hell Creek in search of dinosaurs, and it was in the scabby hills a hundred miles or so southeast of the creek where he found the first skeleton of T. rex in 1902. His bosses in New York were overjoyed, and Brown was given a mandate to bring more fossils back to the big city. Over the next few years, decked out in his fur coat with his pickaxe slung over his shoulder, he prospected the bluffs, gullies, and dry streambeds along the Missouri River and farther southeast. The fossils kept coming, and after a while Brown came to understand the geology of the area. All of the bones were buried inside a thick sequence of rocks that formed much of the badlands topography—a layer-cake array of reds, oranges, browns, tans, and blacks, made up of sand and mud deposited by ancient rivers. He called these rocks the Hell Creek Formation. The Hell Creek rocks were formed between about 67 and 66 million years ago, by a tangle of rivers that drained the young Rocky Mountains to the west, then meandered across a vast floodplain, occasionally bursting their banks and pooling into lakes and swamps, before emptying eastward into that great seaway that cut North America in two. These were fertile, lush environments, a perfect setting for so many types of dinosaurs to thrive. It was also an environment where sediments were being deposited and turned into rock, with the bones inside them along for the ride. Lots of dinosaurs and lots of sediments—that’s the recipe for a fossil bonanza.


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I took my first trip to Hell in 2005, a century after Brown’s T. rex was unveiled in New York. I was an undergraduate, a month removed from my first-ever dinosaur-hunting expedition, excavating Jurassic sauropods in Wyoming with Paul Sereno. Looking to gain additional fieldwork experience, I drove out to Montana with a crew from the closest thing I could call my local museum, the aforementioned Burpee Museum of Natural History in Rockford, Illinois. Rockford isn’t the type of place you’d expect to have a dinosaur museum. For one, not a single dinosaur fossil has ever been found in Illinois—my home state is too flat, too geologically boring, almost barren of rocks formed during the time dinosaurs reigned. Nor have past decades been kind to its manufacturing-based economy. Yet Rockford has one of the finest natural history museums in the Midwest. The staff of the Burpee Museum often refer to themselves as “the little museum that could,” which speaks to the odd twists of fate they’ve had to navigate. For most of its existence, the museum was little more than a fusty collection of stuffed birds, rocks, and Native American arrowheads, poking out of the nooks and lofts of a once-grand nineteenth-century mansion. Then in the 1990s, the museum received a startling donation from a private benefactor, and a new wing was added. Exhibits were needed to fill the expansion, so the administrators hatched a trip to Hell Creek to bring back dinosaurs. At that time, the Burpee Museum had only a single paleontology curator on its payroll, a soft-spoken, barrel-chested northern Illinois boy named Mike Henderson, infatuated with the smeared fossils of worms that lived hundreds of millions of years before the dinosaurs. He needed help, so he teamed up with a childhood friend—a boisterous, loudmouthed people person named Scott Williams. Along with comic books and superhero movies, Scott loved dinosaurs as a kid, but he didn’t have the opportunity to pursue paleontology as a career and ended up going into law enforcement. He was still a cop—and he looked the part, with his goatee, stocky build, and thick Chicago accent—when I first met him at the Burpee Museum when I was in high school. A few years later, after leaving the force for a full-time career in science, he became the collections manager at the museum, and today he helps manage one of the world’s largest dinosaur collections, at the Museum of the Rockies in Montana. During the summer of 2001, Mike and Scott led an eclectic crew of museum staff, geology students, and amateur volunteers out to the heart of Hell. They set up camp near the tiny town of Ekalaka, Montana, population about three hundred, not too far from the T-shaped junction where Montana meets both Dakotas. Brown had once searched this ground, but Mike and Scott found something that had eluded even the maestro. They happened upon the best, most complete skeleton of a teenage T. rex that had ever been found.


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It was the keystone fossil that told paleontologists that the King was a gangly, long-snouted, thin-toothed sprinter as a youngster, before it metamorphosed into a truck-size bone-crunching brute as an adult. Mike, Scott, and their crew discovered a fossil that immediately made the Burpee Museum a major player in dinosaur research. When the skeleton—which they nicknamed Jane, after a museum donor—went on display a few years later, paleontologists from around the world flocked to anonymous Rockford, Illinois, to see it—as did many hundreds of thousands of kids, families, and tourists. The Burpee Museum now had a superstar to headline its new exhibition hall. Mike and Scott kept going back to Hell for months at a time during the next few summers. Eventually they invited me to come along, but only after I earned their trust. I had become friends with Mike and Scott during my frequent visits to the Burpee Museum, which began while I was a high school sophomore. They first knew me as an annoying teenager with a dinosaur obsession, who, tape recorder and autograph Sharpie in hand, religiously attended the Museum’s annual PaleoFest, where notable scientists came to speak about their adventures studying dinosaurs (which, incidentally, is where I first met two of the eminent paleontologists who would later become my academic advisors: Paul Sereno and Mark Norell). I continued to drive up to Rockford throughout college, and once I started formally training to become a paleontologist in Sereno’s lab, Mike and Scott thought I was ready to join them on their annual descent into Hell. A thousand miles separate Rockford and Ekalaka. When we arrived, we took up residence at a place called Camp Needmore, a scattering of wooden bunkhouses deep in the cool pine forests that rise above the badlands. That first night I was kept awake by the wail of a synthesizer, coming from one of the cabins next door. It was the bunkhouse occupied by a trio of volunteers who drove out separately from Rockford, all professionals taking a break from the grind of the office. Their ringleader was a short, quirky fellow. His name—Helmuth Redschlag—conjured up images of an imperious Prussian general, but he was from Middle America, and his job was much more sedate: he was an architect. Each night he partied deep into the morning with his friends—feasting on filet mignon and imported Italian cheeses, sipping fruity Belgian beers to the disco trash beat. Still, every morning he was up at six a.m., eager to head back into the furnace of Hell on the trail of dinosaurs. “It makes me feel alive. The heat. The sun beaming down, burning you, scarring your neck and your back, desperate for shade and water,” Helmuth said to me in the calm of one morning, before we set out into the inferno. Uh huh, uh huh, I nodded along, unsure of what to make of him.


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A couple of days later, while I was out prospecting with Scott and some of the other student volunteers, we got a frantic call from Helmuth. He was wandering a few miles down the road, enjoying the pain of the sun on his skin, when something caught his eye in a gully: a dark brown bulge sticking out of the dull tan-colored mud rocks. A lot of things caught Helmuth’s eye—he was an architect, after all, and a fine one at that—and his attention to the details of shapes and textures made him a very good fossil hunter. He sensed that this one was special, so he started to dig into the hillside. By the time we arrived on the scene, he had exposed a thighbone, several ribs and vertebrae, and part of the skull of a dinosaur. The bones from the head gave away its identity. Many of them were randomly shaped pieces of something flat and platelike, resembling shattered glass, and a few others were sharp, pointy cones: horns. Only one dinosaur in the Hell Creek ecosystem fit the profile: Triceratops, with three horns on its face and a broad, thick, billboard-like frill extending from behind its eyes. Triceratops, like its arch-nemesis T. rex, is a dinosaur icon. In films and documentaries, it usually plays the gentle, sympathetic plant-eater, the perfect dramatic foil to the Tyrant King. Sherlock versus Moriarty, Batman versus the Joker, Trike versus Rex. But it’s not all movie magic; no, these two dinosaurs truly would have been rivals 66 million years ago. They lived together along the lakes and rivers of the Hell Creek world, and they were the two most common species there—Triceratops making up some 40 percent of Hell Creek dinosaur fossils, T. rex coming in second at about 25 percent. The King needed immense amounts of flesh to fuel its metabolism; its three-horned comrade was fourteen tons of slow-moving prime steak. You can figure out what happened next. Indeed, Triceratops bones with bite marks matching T. rex attest to their ancient battles, but don’t think for a moment that it was an unfair fight, always destined to go the way of the predator. Triceratops was armed with a set of weapons: its horns, a stout one on the nose and a longer, thinner one above each eye. Like the frill on the back of the head, the horns probably evolved primarily for display—to make Triceratops seem sexy to potential mates and scary to its rivals—but no doubt Triceratops would use them in self-defense when needed. Triceratops is a new type of dinosaur in our story. It belongs to a group of plant-eating ornithischians called ceratopsians, which descended from some of the small, fast-running, leaf-toothed critters like Heterodontosaurus and Lesothosaurus of the Early Jurassic. Beginning some time in the Jurassic, the ceratopsians went down their own evolutionary path.


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They switched from walking on their hind legs to plodding along on all fours and started to develop a wardrobe variety of horns and frills on their heads, which would get larger and gaudier as a hatchling turned into a hormone-fueled adult that needed to woo mates. The first ceratopsians were dog-size critters; one of them, Leptoceratops, straggled into the Late Cretaceous, where it lived alongside Triceratops, its much larger cousin. As ceratopsids got bigger over time—morphing into bovine versions of dinosaurs that were very common in North America during the latest Cretaceous—they changed their jaws so that they could engulf unholy quantities of plants. They packed their teeth closely together so that the jaws were essentially blades—four in all, one on each side of the upper jaw and one on each side of the lower. The jaws would snap shut in a simple up-and-down motion, the opposing blades slicing past each other like a guillotine. At the front of the snout was a razor-sharp beak, which would pluck the stems and leaves and deliver them to the blades. Triceratops surely was as good at eating plants as T. rex was at devouring meat. The skull of Triceratops, the iconic horned dinosaur. Photo courtesy of the author Finding a Triceratops was another coup for the Burpee Museum, exactly what it needed to accompany the teenage T. rex in the new exhibit space. From the moment Helmuth showed us the bones in the ground, I could tell that Mike and Scott were thinking exactly that. Helmuth too—and as the discoverer of the new dinosaur, he got to give it a nickname. Like me he is a big fan of The Simpsons, so he decided to call it Homer. One day, we surmised, Homer would join Jane in the halls of the Burpee Museum. A jumble of Triceratops bones at the Homer site, belonging to a pack of juveniles. Photo courtesy of the author My field notebook from the 2005 Burpee Museum expedition to Hell Creek, showing the field map of the Homer Triceratops site that I made. Photo courtesy of the author But first we had to get Homer out of the ground. The crew began to wrap up the exposed bones in plaster bandages, to protect them during transport back to Rockford. Others were tasked with finding more bones. Thomas Carr—my absinthe-drinking, Goth-dressing friend who studies T. rex—was with us on the expedition and was part of this team. Clad in khaki (it was far too hot for his usual all-black getup) and sucking down Gatorade by the gallon (absinthe was more of an indoor pursuit), he attacked the mudstones with his rock hammer (which he nicknamed Warrior) and his pickaxe (Warlord), exposing a number of new Triceratops bones. As he and the others pulverized the hillside, more bones were jarred loose. Eventually the excavation site extended for some seven hundred square feet (sixty-four square meters), and yielded over 130 bones.


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It quickly became very complex, so Scott tasked me with making a map—a skill I had learned the previous month from Paul Sereno. I laid out a meter-by-meter grid of string attached to chisels pounded into the rock. Using the grid for reference, I sketched the location of each bone in my field notebook. On the adjacent page I identified each bone, assigned it a number, and made notes on its size and orientation. In this way, we began to make order from the chaos. The map and bone inventory revealed something peculiar. There were three copies of the same bone: three left nasals, the bone that makes up the front and side of the snout. Each Triceratops had only one left nasal, the same way it had only one head or one brain. Then it dawned on us: we had three Triceratopses: not only Homer, but Bart and Lisa too. Helmuth had found a Triceratops graveyard. It was the first time that anybody had found more than one Triceratops in the same place. Until Helmuth walked into that gully, we thought Triceratops was a solitary animal—and we were fairly confident, because Triceratops was so common, already known from hundreds of fossils found over a hundred years, each one a single individual, encountered on its own. But one discovery can change everything, and because of what Helmuth found, we now think that Triceratops was a pack species. It’s actually not too surprising, because there is ample evidence that close cousins of Triceratops—some of the other large, horned ceratopsian species living in other parts of North America during the final 20 million years of the Cretaceous—were social creatures that cohabited in big groups. One of these species, Centrosaurus, which lived in modern-day Alberta about 10 million years before Triceratops and had a giant horn rising from its nose, has also been found in a bone bed—not a modest bonebed like the Homer site, but one covering an area of nearly three hundred football fields and entombing more than a thousand individuals. Several other ceratopsians have also been found in mass graves, providing a wealth of circumstantial evidence that these big, slow, horned, plant-munching species were communal. It brings to mind an evocative image: these dinosaurs probably moved across Late Cretaceous western North America in vast herds, many thousands strong, rumbling the ground and kicking up clouds of dust as they plowed across the landscape, not much unlike the bison that would conquer the same plains many millions of years later. After we finished working the Homer site, we continued to prospect the miles of monotonous badlands around Ekalaka, trying to set out early in the morning to beat the worst of the heat. We found a lot of other dinosaur fossils—nothing as important as Homer, but clues from some of the other animals that shared the latest Cretaceous floodplains with Triceratops and T. rex.


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We discovered scores of teeth from smaller carnivores, including dromaeosaurid raptors of the Velociraptor mold, as well as the chompers of a pony-size animal called Troodon, a close relative of the raptors that had developed a taste for a more omnivorous diet. We also came across some foot bones of human-size omnivorous theropods called oviraptorosaurs—weird, toothless dinosaurs with flamboyant crests of bone atop their skulls and sharp beaks adapted to eat a whole variety of food, from nuts and shellfish to plants and small mammals and lizards. Other fossils pointed to two distinct types of herbivores: a fairly boring ornithischian called Thescelosaurus, about the size of a horse, and a slightly larger and much more interesting creature called Pachycephalosaurus, one of the “dome-headed” dinosaurs with a bowling-ball skull that it used to batter its rivals in fights over mates and territory. We also spent a couple of days excavating at another locality, which we hoped would turn out to be as productive as the Homer site. It didn’t live up to our expectations, but it did produce bones of what is the third most common dinosaur in the Hell Creek formation: another plant-eater called Edmontosaurus. At about seven tons in weight and forty feet (twelve meters) from snout to tail, Edmontosaurus was a big herbivore like Triceratops but of a very different breed. It was a hadrosaur, a member of the duck-billed clan of dinosaurs that evolved from a separate branch of the ornithischian family tree. They were also very common in the Late Cretaceous—particularly in North America—and many of them lived in herds, walking on either two or four legs depending on how fast they wanted to move, and communicating with bellowing sounds produced by the convoluted spaghetti-twisted nasal chambers within their elaborate head crests. Their nickname comes from the broad, toothless, ducklike bill at the front of their snout, which they used to snare twigs and leaves. Like ceratopsians, their jaws were modified into scissors for slicing—but with even more, and more tightly packed, teeth. Nor were their jaws limited to simple up-and-down movements, but they could pivot from side to side and even hinge outward a little bit, allowing for complex chewing motions. They were some of the most intricate feeding machines ever produced by evolution. Pachycephalosaurus, the dome-headed, head-butting dinosaur from Hell Creek. Photo courtesy of the author The hadrosaurs, and probably also the ceratopsians, had these sophisticated jaws for a reason. They were fine-tuned by evolution to feed on a new type of plant that had arisen earlier in the Cretaceous: the angiosperms, more commonly known as the flowering plants. Although flowering plants are exceedingly abundant today—the source of much of our food, the décor in many of our gardens—they would have been unknown to the first dinosaurs rising up on Pangea in the Triassic. They were likewise unfamiliar to the giant long-necked sauropods of the Jurassic, which instead inhaled other types of vegetation like ferns, cycads, ginkgos, and evergreen trees.


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Then, about 125 million years ago, in the Early Cretaceous, small flowers emerged in Asia. With another 60 million years of evolution, these proto-angiosperms had diversified into a range of shrubs and trees, including palms and magnolias, that dotted the Late Cretaceous landscape and that were tasty fodder for the new types of herbivorous dinosaurs that could eat them. There may have even been a little bit of grass—a very specialized type of angiosperm—sprinkled on the ground, but proper grasslands would not develop until much later, many tens of millions of years after the dinosaurs cleared out. Hadrosaurs and ceratopsians eating flowers. Smaller ornithischians feeding on shrubs, the pachycephalosaurs head-butting each other in tests of dominance. Poodle-size raptors prowling for salamanders, lizards, even some of our early mammal relatives, all of which are known from Hell Creek fossils. A variety of omnivores—Troodon and the freakish oviraptorosaurs—picking up whatever scraps the more specialized meat-eaters and plant-eaters forgot about. Other dinosaurs I haven’t yet mentioned, like the speed-demon ornithomimosaurs, and the heavily armored Ankylosaurus, fighting for their own niches. Pterosaurs and primitive birds soaring overhead; crocodiles lurking offshore in the rivers and the lakes. Not a sauropod to be found, and the King—the great T. rex itself—ruling over all of it. This was the Late Cretaceous of North America, the final flourish of the dinosaurs before disaster struck. Because of the wealth of fossils discovered by everyone from Barnum Brown to the teams from the Burpee Museum, it is the single richest dinosaur ecosystem known to science during the entire Age of Dinosaurs anywhere in the world, our best picture of how a variety of dinosaurs lived together and fit together into one food chain. It was much the same story in Asia, where big tyrannosaurs like my Pinocchio rex reigned over communities of duckbills, domeheads, raptors, and theropod omnivores—due to the close physical proximity with North America that allowed regular exchange of species between the two continents. Meanwhile, south of the equator, things were much different. ALMOST SMACK IN the middle of Brazil is a gently rolling plateau that was once covered by woodland savannah but is now prime farming country. There people grow some of the same crops found in the fields that stretch between my hometown and the Burpee Museum—mostly corn and soybeans—but also more exotic things like sugarcane, eucalyptus, and a whole host of delicious but unfamiliar fruits. This area is called Goiás, and it’s a landlocked state of some six million residents, crisscrossed by lonely highways. The national capital, Brasília, is a few hours away, and the Amazon surges a thousand miles to the north. Few foreign tourists ever make it here. Goiás, however, holds many secrets. You wouldn’t know it from the mundane topography, but underneath the farms is a hidden landscape, one that was on the surface between 86 and 66 million years ago.


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It is a terrain of windblown deserts on the fringes of great river valleys, represented today by a thousand-foot-thick basement of rocks, the foundation for the corn and bean fields. These rocks were molded out of the sand dunes, rivers, and lakes of the Late Cretaceous, in what was then a great basin formed from the residual stresses of South America and Africa cracking apart. This basin was a haven for dinosaurs. The Cretaceous rocks of Goiás remain mostly buried, but they do poke up here and there, along roads or stream banks. The best place to see them, though, is in quarries, where heavy machinery has torn through the earth to expose the layers of sandstone and mudstone beneath. That’s where I found myself one day in early July 2016, the beginning of the austral winter but still hot and muggy, adorned with a hard hat to save my scalp from falling stone and shin guards up to my knees to protect against an even greater danger: snakes. I had been invited to Brazil by Roberto Candeiro, a professor at the Universidade Federal de Goiás, the main university in the state, and an expert on the dinosaurs of South America. I had excavated and studied a lot of Late Cretaceous dinosaurs in North America and Asia, but Roberto advised me to get a southern perspective. He didn’t mention snakes as part of the deal. A few years earlier, Roberto had started a new undergraduate geology program at his university’s palm-lined campus on the rapidly growing outskirts of Goiânia, the state capital. The bleached white of the lecture halls—whose corridors were open to the breezy subtropical air—contrasted with the dirt streets and aluminum-roofed shanties just a few miles away. Mopeds growled their way through traffic while old men chopped coconuts with machetes on the roadsides, and monkeys swung from the trees in the distance. The next time I return, many of these remnants of old Brazil will probably be gone. The excitement of the new course, on the sparkling campus in the biggest city around, attracted a number of keen students, some of whom were joining Roberto and me on the trip to the quarry. There was Andre, a vivacious, potbellied comedian going back to school after trying out many different careers—papaya grower, taxi driver, and years ago a ranch hand in charge of manually deseminating male, and artificially inseminating female, pigs on one of those big farms in the flatlands. Much younger was eighteen-year-old Camila, a short wisp of a woman whose stature belies her boundless energy and ferocity—she relieves stress by kickboxing in her spare time. And then Ramon, a tall, tanned heartbreaker who, with his skinny jeans and hair slicked over to one side, could have leaped right out of one of the Brazilian boy-band music videos that seemed to be playing on every restaurant television.


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The quarry we were gathered in was owned by a young guy whose family had been farming in central Brazil for generations. They mined the rock for fertilizer. It is a strange type of stone that looks like concrete, with pebbles of various shapes and sizes embedded within a white matrix. The white stuff is limestone; the pebbles are various rocks that were washed around by the raging rivers of latest Cretaceous Brazil. Among those pebbles are rare bones—dinosaur fossils. Maybe one out of every ten or twenty thousand of them is bone instead of boulder, but whatever bones you can find are treasure, because they are the remains of some of the last dinosaurs of South America, those species living around the same time as T. rex, Triceratops, and the Hell Creek gang up north. Roberto Candeiro searching for fossils in Goiás, Brazil. Photo courtesy of the author Alas, after many hours of searching, we didn’t find any bones in the quarry when I visited. We also didn’t get bitten by any snakes, so it was a rare day when I came home from the field empty-handed but happy. Later during the trip, we did find some bones in other places, but only fragments. There would be no new species this time—which is often the case when you’re exploring a new area, because finding totally new dinosaurs is a hard job, dependent on luck and circumstance. But Roberto has led many such field trips over the past decade, often taking along his motley crew of students, and they’ve found a lot of bones. Roberto keeps some of them in his lab in Goiânia, where I spent the remainder of my time in Brazil working with Roberto and another of his buddies, an oil-company geologist named Felipe Simbras, who studies dinosaurs as a hobby. When you look at the fossils shelved in Roberto’s lab, it’s striking to see no T. rex. No tyrannosaurs of any kind, in fact, are known from the latest Cretaceous of Brazil. Spend a day walking through the Hell Creek badlands in Montana, and you’ll probably find several T. rex teeth—they’re that common. But zilch in Brazil, or anywhere else in the southern half of the planet. Instead, Roberto has drawers of other types of carnivorous dinosaur teeth. Some of these belong to a group that we’ve already met: the carcharodontosaurs, that clan of mighty meat-eaters that evolved from the allosaurs and terrorized much of the planet earlier in the Cretaceous. A few of them, like Carcharodontosaurus from Africa, which I studied with Paul Sereno, eventually reached sizes rivaling T. rex. Up north, the carcharodontosaurs came and went, ruling for tens of millions of years before ceding their crown to the tyrannosaurs in the middle Cretaceous. Down south they persisted to the very end of the Cretaceous, retaining their heavyweight title because there were no tyrannosaurs around to take it. Another type of tooth is commonly found in Brazil.


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They’re also sharp, serrated blades, so they must have come from the mouth of a carnivore, but they are usually a little smaller, more delicate. They belong to a different group of theropods called abelisaurids, an offshoot of fairly primitive Jurassic stock that found the southern continents ripe for the taking during the Cretaceous. A decent skeleton of one, called Pycnonemosaurus, was found one state over from Goiás, in Mato Grosso. The bones are fragmented but are thought to belong to an animal that was about thirty feet (nine meters) long and weighed a couple of tons. Even better skeletons of abelisaurids have been found farther south, in Argentina, while others have been discovered in Madagascar, Africa, and India. These more complete fossils—Carnotaurus, Majungasaurus, and Skorpiovenator among them—reveal abelisaurids as fierce animals, a little bit smaller than tyrannosaurs and carcharodontosaurs, but still at or near the top of the food chain. They had short, deep skulls, sometimes with stubby horns jutting out from near the eyes. The bones of the face and snout were encrusted with a rough, scarred texture, which probably supported a sheath made of keratin. They walked on two muscular legs like T. rex, but had even more pitiful arms. Although it was thirty feet (nine meters) long and 1.6 tons in weight, Carnotaurus had arms barely bigger than a kitchen spatula, which flopped around in a useless way, probably all but invisible if you were watching it go about its everyday business. Clearly the abelisaurids didn’t need their arms, relying on their jaws and their teeth for all of the dirty work. That dirty work, for both abelisaurids and carcharodontosaurids, was catching and chomping the other dinosaurs they lived with, particularly the plant-eaters. Some of them were similar to northern species—for example, some duck-billed dinosaurs have been found in Argentina. But for the most part, it was a different bunch of herbivores down south. There were no pulsating herds of ceratopsians like Triceratops, and no dome-headed pachycephalosaurs. There were, however, sauropods. Hordes of them. T. rex didn’t chase down any of these long-necked titans up in ancient Montana, as sauropods seemed to have disappeared from most of North America some time during the middle part of the Cretaceous (although they still did frequent the southern reaches of the continent). Not so in Brazil or the other austral lands. There sauropods remained the primary large-bodied plant-eaters, right up to the end of the Age of Dinosaurs. It was one particular type of sauropod that spread across the southlands. The halcyon days of the Jurassic were far gone, and no longer did Brachiosaurus, Brontosaurus, Diplodocus, and their ilk crowd together in the same ecosystems, finely dividing the niches between them with their distinctive teeth, necks, and feeding styles. What was left at the end of the Cretaceous was a more restricted roster of sauropods, a subgroup called the titanosaurs.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.14

Some were truly Biblical in proportions—like Dreadnoughtus from Argentina or Austroposeidon, described by Felipe the oilman and his colleagues from a series of vertebrae—each one the size of a bathtub—found directly south of Goiás in São Paulo State. It’s the largest dinosaur ever found in Brazil, and probably stretched about eighty feet (twenty-five meters) from snout to tail. It strains the senses to envision what it must have weighed, but probably somewhere in the ballpark of twenty to thirty tons, maybe much more. Other late-surviving southern titanosaurs—from Brazil and elsewhere—were considerably smaller. The so-called aeolosaurins were modest creatures, at least as sauropods go, with some of the better-known species, like Rinconsaurus, at a mere four tons and thirty-six feet (eleven meters) long. Another subgroup, called saltasaurids, were of the same general size, and they protected themselves from the hungry abelisaurids and carcharodontosaurs with a patchwork of armor plates implanted in their skin. We also know that there were some smaller theropods but nothing like the panoply of small to midsize carnivores and omnivores in North America. Maybe, you could argue, we just haven’t found their small and delicate bones yet, but that’s not a very satisfying explanation, because there are many skeletons of similar-size animals found in Brazil, but they are crocodiles, not theropods. Some of them were fairly standard water dwellers that probably wouldn’t have competed very much with dinosaurs, but others were bizarre animals adapted for living on the land, so unlike today’s crocs. Baurusuchus was a long-legged, doglike pursuit predator. Mariliasuchus had teeth that looked like the incisors, canines, and molars of mammals, which it probably used like pigs to eat a smorgasbord omnivorous diet. Armadillosuchus was a burrower with bands of flexible body armor, and it may have been able to roll up in the style of an armadillo, hence its name. None of these animals lived in North America, as far as we know. It seems that, in Brazil and throughout the Southern Hemisphere, these crocodiles were filling ecological niches held by dinosaurs in other parts of the world. Carcharodontosaurs and abelisaurids instead of tyrannosaurs, sauropods instead of ceratopsians, swarms of crocs instead of raptors, oviraptorosaurs, and other small theropods. The north and the south were different from each other during those waning years of the Cretaceous, that much is certain. But these big continental areas were downright normal—boring, even—compared to what was going on at the same time in the middle of the Atlantic, where some of the weirdest dinosaurs to ever evolve were hopping around the flooded remnants of Europe. OF ALL THE people who have ever studied dinosaurs, collected dinosaur bones, or even thought about dinosaurs in any serious way, there’s never been anybody quite like Franz Nopcsa von Felső-Szilvás. Baron Franz Nopcsa von Felső-Szilvás, I should say, because this man was literally an aristocrat who dug up dinosaur bones.


The rise and fall of the dinosaurs [eBook - NC Digital -- Steve Brusatte -- 1, 2018 -- William Morrow -- 9780062490421 -- 819b642fffa68675f9e07cf3af773125 -- Anna’s Archive.15

He seems like the invention of a mad novelist, a character so outlandish, so ridiculous, that he must be a trick of fiction. But he was very real—a flamboyant dandy and a tragic genius, whose exploits hunting dinosaurs in Transylvania were brief respites from the insanity of the rest of his life. Dracula, in all seriousness, has nothing on the Dinosaur Baron. Nopcsa was born in 1877 to a noble family in the gentle hills of Transylvania, in what is now Romania but was then on the fringes of the decaying Austro-Hungarian Empire. He spoke several languages at home, and they instilled within him an urge to wander. He also had urges of another kind, and when he was in his twenties, he became the lover of a Transylvanian count, an older man who regaled him with tales of a hidden kingdom of mountains to the south, where tribesmen wore dapper costumes, brandished long swords, and spoke in an indecipherable tongue. The local mountain men called their homeland Shqipëri. We know it today as Albania, but then it was a backwater on the southern edge of Europe, occupied for centuries by another great empire, the Ottoman. The baron decided to check it out for himself. He headed south, through the borderlands that separated two empires, and when he arrived in Albania, he was welcomed with a gunshot, which sliced through his hat and narrowly missed his skull. Undeterred, he proceeded to cross much of the country on foot. He picked up the language, grew his hair long, started dressing like the natives, and earned the respect of the insular tribes nestled among the mountain peaks. But the tribesmen might not have been so welcoming if they’d known the truth: Nopcsa was a spy. He was being paid by the Austro-Hungarian government to provide intelligence on their Ottoman neighbors, a mission that became even more critical—and dangerous—as the empires collapsed and the map of Europe was redrawn in the hellfires of World War I. That’s not to say that the baron was merely a mercenary. He was enamored of Albania—obsessed, really. He became one of Europe’s leading experts on Albanian culture and came to truly love its people—one in particular. Nopcsa fell for a young man from a sheepherding village in the high mountains. This man—Bajazid Elmaz Doda—nominally became Nopcsa’s secretary, but he was so much more, although it wasn’t spoken about so openly in those less accepting times. The two lovers would remain together for nearly three decades, enduring the leers of their peers, surviving the disintegration of their respective empires, traveling Europe by motorcycle (Nopcsa on the bike, Doda in a sidecar). Doda was by Nopcsa’s side when, in the chaos before the Great War, the baron plotted an insurgency of mountain men against the Turks—even smuggling in firearms to build an arsenal—and then later tried to install himself as king of Albania. Both schemes failed, so Nopcsa turned to other pursuits.