T. rex vs. Prey: Imagining battles between ancient gladiators

When I was super young, say around five or so, I remember playing in the bath tub with my plastic toys. Some were super heroes like He-Man or Teenage Mutant Ninja Turtles, others were monster trucks and die-cast matchbox cars by Mattel, but most were dinosaurs.

This might be TMI, this story about the kid in the bath tub with bubbles on his head, ramming plastic characters into one another and dreaming up their backstories, the bellows of challenge they traded, and the choreography of their battles, but I know there are other adult children out there with similar memories.

During this epoch in the evolution of me, I distinctly recall pitting Tyrannosaurus rex against Stegosaurus, which, as I’ve discovered in later life, was completely wrong, as was most of what I thought around five years old, but you know, who can blame a five-year-old for muddling up the fossil record?

T. rex is one of the most famous dinosaurs in history, easily identified by its massive, heavy skull, long steak-knife teeth, powerful back legs and tail, and ridiculous vestigial arms, but due to her status as dinosaur royalty, the length of her reign and her identity is as often confused by adults as it is by naive five-year-olds. The T. rex lived for two million years in the Late Cretaceous, never in the Jurassic, as her appearance in Jurassic Park might suggest, but we can forgive this fiction for its oversight. (After all, InGen, the engineering firm responsible for cloning extinct dinosaurs in the movie, infamously mismatched animals from different eras within the same park.) And she wasn’t the only two-legged carnivore.

stego allo

In a dramatic representation, Stegosaurus and Allosaurus duke it out in the Jurassic. Morian Hall.

In the time of Stegosaurus, between 155 and 150 million years ago (the real Jurassic), the apex predator was the Allosaurus. Smaller than the T. rex, but with more capable arms with three fingers ending in talons, this baddie no doubt picked battles with Stegosaurus, putting its life on the line for a meal. With its polygonal plates down its back, viciously spiked tail, flexible spine and toes that allowed it to rear up, Stegosaurus could give Allosaurus a true walloping.


Allosaurus remains feature prominent eyebrow ridges and three-fingered hands with sharp claws.

Forget about jaws and claws. One solid hit from the bone spikes could deeply puncture the neck or torso of any shady Allosaurus looking for a bite, and its plates would protect its spine from being severed by teeth until it could land a blow. It isn’t difficult to imagine eyes gouged and jugulars perforated, many Allosauruses bleeding out after botched predatory encounters with Stegosaurus. There were certainly easier things for Allosaurus to eat, but few battles with other species could match the gladiatorial epicness of this match-up, at least not in this era.


Even as an herbivore, Stegosaurus would have made a formidable opponent against Allosaurus in the Jurassic, using a spiked tail and bone plates along its spine as defenses.

Fast forward 90 million years to the Late Cretaceous, the reign of the “tyrant lizard.” Tyrannosaurs roamed North America and Asia, preying on a variety of other famous megafauna like Triceratops, Ankylosaurus, and duck-billed hadrosaurs including Edmontosaurus, Brachylophosaurus, and Parasaurolophus. There’s no way T. rex even knew Stegosaurus was a thing. More time passed between these two than between dinosaurs and Homo sapiens.


As the largest predator of the Late Cretaceous, the T. rex is one of the fossil record’s most iconic species.

Nor was the T. rex the only one of her kind; she was just the largest, hence the name, “king of tyrants.” Among her smaller contemporaries, Tarbosaurus, Albertosaurus, Daspletosaurus, and Gorgosaurus, she was the Queen B, big and bad, in spite of the competition. She had excellent vision, a sense of smell that could detect prey from miles away, and decent hearing, though high-pitched sounds would have been lost to her. Food wouldn’t have been difficult for the T. rex to find, but that food really, really didn’t want to be eaten.


T. rex couldn’t have fought Stegosaurus, but it preyed upon Triceratops, another iconic species that lived in the same time period.

There’s no more famous match-up than Tyrannosaurus rex and Triceratops. With two long horns and a bony frill like a samurai helmet to guard its neck, as long as the trike met the T. rex head-on, there was no contest. But if Triceratops charged and missed the mark, the tyrant’s big jaws could take out its backbone in a single bite, neutralizing the threat of horns. Recent discoveries of casts of Triceratops‘s hide reveals nodules that might have housed quills, making even a bite to its back a dangerous one if T. rex ever got around the impenetrable helmet. You can imagine this battle yourself in the Morian Hall of Paleontology, where Lane the Triceratops takes a defensive position under an aggressor T. rex.


T. rex preyed upon Denversaurus and its famous cousin, Ankylosaurus, but both would have made a difficult meal, protected by bony armor.

Against Ankylosaurus and its cousin Denversaurus, also on display in Morian Hall, tyrannosaurs likely had a more difficult time. Both Ankylosaurus and Denversaurus developed the adaptation of a wide, low body and armored plating, making access to its soft underbelly impossible for tyrannosaurs unless kicked onto its back, but Ankylosaurus had another advantage. The tip of its tail bore a mace-like club that, like Stegosaurus’s spiked tail, could maim the jaws of predators that didn’t pay enough heed. One swing from this heavy weapon could break open a T. rex‘s face, cripple its legs, or shatter its ribs, and with arms too small to defend itself, dodging seems the only tactic at her disposal against this tank of a creature. An encounter with an Ankylosaurus could mean either a meal or certain death, depending on the T. rex‘s experience hunting.


Armor plating on the back of Denversaurus would have protected against a bite from the T. rex and other tyrannosaurs of the Late Cretaceous, but if flipped over, its soft underbelly would be exposed.

A more easy meal for any tyrannosaur would have been Edmontosaurus and other duck-billed dinosaurs. These hadrosaurs had few defenses. No armor plating, no spikes, no claws, no wings, no sharp teeth. But it’s possible they had a different advantage, though it’s tough to deduce through fossils alone. Hollow chambers in the skulls of many hadrosaurs suggest these creatures, like geese and other water fowl, had the power of sound at their disposal. A deafening bellow might have stopped a tyrannosaur in its tracks or sent it running in the other direction. T. rex isn’t known for its sensitive hearing, but as we all know, if the sound is loud enough, it can be excruciating. And T. rex had no fingers to put into her ears, nor could she reach them.


Edmontosaurus, a duckbilled hadrosaur and cousin of Parasaurolophus, appears to have lacked natural defenses. However, the hollows in its skull suggest it could have protected itself with deafening bellows like giant geese.

Understanding these species as they once were, interacting with one another, is more than bath tub child’s play for paleontologists; it’s a career and a discipline. It’s in the Greek roots of the word “paleontology,” the study of being and beings in the ancient world. The study of what life on Earth might have looked like eons ago. The work of these scientists is more like philosophy than fiction, but building careful theories via the fossil record and considering every angle does require a measure of imagination.


An artist’s representation depicts Triceratops and Tyrannosaurus rex in an age-old feud set in the lush swamps of the Late Cretaceous, an imagined scene deduced from evidence in the fossil record. Morian Hall.

I suppose, apart from the spikes and teeth and horns and claws and body armor and all the other things that make these terrible lizards seem like something out of science fiction, or monsters invented by a puppeteer, it’s the daydreaming paleontology requires that holds my attention. To understand their world, you must build it in your mind.

Bakker Blogs: Rapscallion dino rustlers and the paleontological gold rush of the American West

Part One: Allosaur-Rustlers of the Old West.

It’s 1879, and we’re in the Old West. Como Bluff, Wyo., to be exact. It’s hot, it’s dusty, and it’s full of rustlers.

There’s a Jurassic Gold Rush going on — a paleontological stampede to get the best dinosaur skeletons out of the rock and back into museums. Two “Bone Barons” are out in force, trying to be the first to score Mesozoic giants.

Professor Othniel Charles Marsh from Yale University got here first. In 1877, two railroad hands working in Laramie County, Mr. Harlow and Mr. Reed, had telegraphed the Yalie scientist with the galvanic announcement: “We’ve found huge bones. Plenty of them.  Easy to dig and haul to the station for shipping back East. Send money.”

Marsh sent money — his own money.  He was using up his inheritance to fill the Yale museum. In the first 18 months at Como, Yale got tons of rock full of gorgeous ebony-hued bones. New species galore! No one had seen such glorious relics from the Late Jurassic Period before. Marsh zipped out preliminary scientific papers on Morosaurus, Laosaurus, Dryosaurus, Camptosaurus and Brontosaurus. The specimens were so complete that Marsh’s anatomical illustrators could generate beautiful diagrams of the entire skeleton, nose to tail. Marsh and his dinos scored front-page headlines in newspapers and magazines in a dozen languages.

Meanwhile, in Philadelphia, the other Bone Baron, Edward Drinker Cope, seethed with jealousy. Though he was from an old Quaker family, Cope was overcome by emphatically un-Christian thoughts. “I’ve gotta get some Jurassic bones from Wyoming…no time to find my own quarries….gotta hire some independent diggers, men with more moxie than scruples.”

Marsh’s crew at Como Bluff heard the rumors about Cope’s devious plan. Some surly no-goodnicks were trolling through the local bars asking questions about what had been excavated and where. So the Yale crew armed themselves with pickaxes, shovels and Winchester rifles. Unwelcome visitors, they figured, would be bombarded with chunks of black Jurassic rock and, if need be, a barrage of .44 caliber bullets fired in a great cloud of black-powder smoke.

But Como Ridge is too wide — 12 miles east to west — and the three or four Marsh men couldn’t patrol the entire outcrop. Word came from the freight manager at Como Station that some chaps had, indeed, sent big crates of rock to the address: “E. D. Cope, Philadelphia.”

What had the pirates dug up? The Yale crew scoured the landscape for tell-tale marks of recent digging. “There it is, next to our old Brontosaurus quarry — a huge hole!” The excavation was big enough to mark the spot where a mid-sized dino had been lifted out, a beast maybe 30 to 35 feet long. What species? There was no clue. The rustlers had been thorough; they didn’t leave a scrap of identifiable bone.

The Yale folks muttered curses and Old West imprecations and treated themselves to dinner at Laramie, a three-hour ride from the diggings.

No one at Yale ever learned who had stolen what. But in an odd twist of fate, the nefarious Quaker Cope was no wiser. Yes, he paid “F. F. Hubbell” and his brother for three loads of bones stolen from Como. Yes, he opened the first two sets of crates and poked around inside. “Jurassic junk,” Cope muttered. “Bits and pieces, nothing important. Those Hubbell brothers wouldn’t know a significant fossil if it came alive and bit them on the boot.”

Cope was discouraged. His lapse into scientific larceny hadn’t paid off. Maybe his Mother’s Christian admonitions had come to haunt him. Anyway, Cope retired from the rustling business. He paid the Hubbell Brothers for their last shipment but didn’t bother opening the final set of crates.

Fast forward to 1901. Setting: the brand new American Museum of Natural History at Central Park West in New York City. Professor Henry Fairfield Osborn was in charge, and he had more money than Cope and Marsh put together.  Thanks to a generous millionaire on the Board, Osborn had arranged to buy all of Cope’s fossils in the late 1890s. Cope and his estate needed the funds, because the family fortune had been spent down to the last penny in the quest for prehistoric trophies. Osborn hired the brightest and best young men in paleontology — many of whom had worked with Cope or Marsh or both.

Dr. Jacob Wortman oversaw the unpacking. He had risked life and limb for Cope in the wildest parts of Wyoming in the early 1880s. Then he had led Osborn’s first field parties to Como Bluff in 1897. Now he was in charge of the biggest purchase of fossils ever made. Exclamations of joy came from the American Museum crew as box after box was opened. Many of the specimens were world-famous, their images spread across scientific monographs and textbooks.

And that last shipment from the Hubbell Brothers? Since it had never been opened, the crate was dusty and the shipping label was faded. “Leave it till last…those brigands never dug up anything worthwhile,” the crew must have thought.

So it was not until 1904-1905 that the crates had their lids pried off. Cheap wood splintered. Rusted nails fell to the floor. Osborn’s men looked in…

Inside was not what they expected. Filling the crates was not a mass of useless paleontological bric-a-brac. That last shipment contained just one, single specimen — a nearly complete skeleton of the apex predator who had ruled the Late Jurassic ecosystem: Allosaurus.

L-Allo on apato greyHubbell

Marsh had named Allosaurus fragilis from a pretty good skeleton dug in Canon City back in the 1870s. The Hubbell Brothers’ beast was twice the bulk, clearly from a later, more advanced species. Apex predators are always the rarest finds, because these top carnivores needed such large populations of prey species as a food base. Dozens of Jurassic herbivores had been announced but only a handful of Apex meat-eaters. The Hubbell Brothers’ animal was the biggest and finest dino-carnivore known from the entire Jurassic Period.

Osborn jumped on the new opportunity: the Allosaurus would be the new exhibit’s top priority. Bits of rock flew off the bones as micro-chisels were employed by skilled fingers. Broken sections were expertly glued together with gum arabic. Artists who worked bending iron prepared a graceful armature of braces that held every vertebra, every toe bone in proper anatomical position.

Osborn was an unusual paleontologist. His educated imagination saw every skeleton as a living, breathing being. He loathed mounts that were stiff and clumsy. His would capture the sinuous grace of the beasts in the full bloom of health.

What is the most vivid way of showing the Hubbell allosaur?  In the act of feeding on its prey.  Jake Wortman had brought back from Como a brontosaur specimen that was a genuine CSI exhibit. The tops of the vertebrae had been bitten by some huge, unknown predator. In the rock next to the bronto were tooth crowns from the perpetrator. Now that he had the Hubbell Brothers specimen for comparison, Osborn could identify the perp — it was a giant allosaur the same size as the Hubbell skeleton.

The CSI evidence fell into place. Wortman and his fellow diggers had found the old Hubbell Brothers’ excavation site and mapped the location. It was only a quarter mile from where they dug up that chewed brontosaur and in the same layer of rock. The esteemed allosaur might have been the very same individual that snacked on the Brontosaurus!

To Osborn, the design of the exhibit was crystal clear.  The Hubbell allosaur would be mounted as if it was still chewing flesh and bone from the brontosaur carcass. When the display opened to the public in 1907, both the public and the scientific community were astounded. For the first time, Jurassic bones came alive.  The mount became the most famous dinosaur display ever seen. To this day, there is no Jurassic exhibit that is superior, and few exhibits have equaled it.

As for the Hubbell Brothers, did they live to hear about their specimen or see its image on the cover of Scientific American? We do not know. After 1879 and their last shipment to Cope, they disappeared. There is doubt that their real name was even Hubbell. Allegedly they were from Minnesota, but no record can be found.

Stay tuned for Part II.

What a Croc!

Today’s guest blogger is Neal Immega. He has a Ph.D. in Paleontology and is a Master Docent here at HMNS. In his post below – originally printed in the Museum’s volunteer newsletter– Neal discusses the Geosaurus, a fossil featured in our exhibition Archaeopteryx: Icon of Evolution.

The Houston Museum of Natural Science has a new exhibit, “Archaeopteryx: Icon of Evolution” that features the best Archy ever.  Do not let that blind you, though, to the other critters on display. One of these is the best marine crocodile anywhere, a Geosaurus with an exciting evolutionary story all its own. These animals have a worldwide distribution from Brazil to Germany, but this specimen is the most complete, and shows the soft parts. Ah, the preservation of fossils in the Solnhofen limestone is amazing.

Let’s see what observations we can make from the skeleton and what conclusions we can draw. Look at this picture and get an overall impression of the fossil. The label says it is a croc, but is it? It does not look like any croc I have ever seen.

Complete Geosaurus skeleton, with skin impressions, from the Solnhofen limestone.
Geosaurus skull showing croc dentition

Head: The front end certainly looks like a modern crocodile head. The teeth are conical and striated, with the typical croc dentition:  teeth are located inside and outside the jaw line, and there are large teeth half way down the jaw.  Modern crocs use them for breaking turtle shells (see the YouTube video referenced below).

Tail: Ok, so it is a croc but it does have a very strange tail. Let’s look more closely at the tail to see if there is any support for the decision the preparator made to indicate a tail like a shark’s.

The faint skin impressions support
interpretation as a shark-like tail.

The discolored rock strongly suggests that the tail does have a shark outline, unlike that of all known modern crocodilians. Even better, compare the caudal processes (bumps on the top of the vertebra) in the area of the fin to those farther up the spine.  The processes in the tail fin area are longer and reverse orientation: they point toward the head, possibly as support for the fin. The fin is real!

Armor: This croc does not have any! There are no osteoderms (bony plates inside the skin) anywhere. The osteoderms in modern crocs do not provide complete coverage and thus are not much use as armor; however, a modern croc has muscles between its osteoderms that can stiffen up the skin during rapid land movements.  Apparently Geosaurus got along without them.

Legs: The arms are very short in proportion to the legs, quite unlike modern crocs.

Salt Gland: Many animals have glands to secrete sodium chloride because they live in or on life from the ocean and eat way to much salt. This animal is said to have chambers in the skull for a salt gland, but I cannot see it. I guess I will take their word* for it. A modern croc has a salt gland in its tongue while many birds have theirs in the skull.

Analysis: Modern crocs are slow swimmers and, thus, ambush predators. A shark-like tail suggests this was a higher speed predator. A modern croc has about 5% of its weight in osteoderms and their absence would improve the water speed at the expense of land speed. I think we have caught this croc species in the transition stage of becoming a true marine predator. It still had clawed limbs to crawl out on the land (to mate and lay eggs) but their smaller size would certainly help reduce drag. If this evolutionary path had continued, the croc’s descendants might have ended up looking like Ichthyosaurs, air-breathing reptiles that gave live birth and looked remarkably like modern dolphins. Remember, a saltwater croc in Australia is called a marine crocodile, but it does not have many adaptations to live in the marine environment besides a salt gland in its tongue.

An Ichthyosaur is a reptile completely adapted to a marine environment.
What happens when a Steneosaurus trys to
ambush an Allosaurus at the water hole

There are other crocs found in the Solnhofen limestone, including long-legged land crocs, dwarf ones, and a substantially armored one, Steneosaurus, featured by Dr. Bakker in this wonderful drawing.

To read more about the Geosaurus, check out Dr. Bakker’s blog.


Wikipedia:  Criosaurus , Dakosaurus, Geosaurus
A nice discussion of aquatic crocs is at  http://en.wikipedia.org/wiki/Cricosaurus

Modern croc using those teeth on a turtle: “ahmedsadat” posting on YouTube, 2008, “Crocodile eats turtle”,  http://www.youtube.com/watch?v=cSKAXOFvi6c

*Salt glands – it is claimed that the skulls have a chamber for salt glands see Fernández and Gasparini, 2008, Naturwissenschaften. 2008, 95(1):79-84. Epub 2007 Aug 22. http://www.ncbi.nlm.nih.gov/pubmed/17712540

Dwarf crocs from the Solnhofen limestone, page 36 in Wellnhofer, 2009, Archaeopteryx, Icon of Evolution, Verlag Dr. Friedrick Pfeil.

All pictures by Neal Immega except the Dino/Croc fight which is by Dr. Bakker.

Not having fun…Stick your head in it!

Museums are generally fascinating places to be and I, especially, love them.  Working at HMNS, I get to see dinosaur bones, snails’ teeth (yes, they have teeth –radula, actually), and spiffy seal-gut parkas on a daily basis. And let me just tell you, it never gets old!  However, on a recent Museum visit with my friends, I noticed that a few of them did not share my enthusiasm, to say the least.  It was a problem that demanded my immediate attention.

Being a huge proponent of edutainment, I turned to them with my camera and simply said, “Hey!  Wouldn’t putting our heads and/or selves INSIDE of some of these things be amazingly fantastic?”  I have found this perspective particularly conducive to a fun, creative learning atmosphere in the past. 

[NOTE: I do not recommend actually sticking your head inside most of what you find in a museum.  Drinking fountains?  Sure!  Large Plexiglas bubbles that make you feel like you are in a kitchen full of cockroaches?  I sure hope so!  (Actually, you can do this in the Brown Hall of Entomology!)  But things that may be extremely rare or fragile, have electric components and really anything sharp…definitely not. What you want to do is create the appearance of being inside the object making clever use of perspective – see below.]

My first ‘volunteer’ was somewhat reserved, but when she stuck her head “inside” that geode, BOY did her face light up!  I have included a few pictures of us as we rediscovered the Woodlands Xploration Station.  As a side note, if you see something particularly tantalizing, cranially speaking, but out of your reach, just take a picture!  All you need to do is frame the shot so it appears you are being devoured by an Allosaurus, without actually getting in his mouth, for example. 

By the end of our visit, everyone involved had a greater appreciation of all the wonders a Museum has to offer, as well as a new-found awareness of their fellow craniates and their shared vantages.

I suggest first trying this method in familiar territory.  Perhaps in some as-yet unexplored corner of your closet, or even stick your head briefly in the bottom shelf of your fridge!  Can you tell me what’s in there right now?  I sure can’t, and maybe I don’t want to know what happens when you leave a slice of buttermilk pie from Christmas dinner unopened for a month…but isn’t it an enticing proposal, nonetheless?  If neither of these suggestions float your boat, you can always put your face in a tree or next to the ground.  Getting that up close and personal with nature herself opens up all of the tiny worlds that surround us.

You now have the curiosity and the tools to become a modern-day Amerigo Vespucci; go forth and explore!