A Tale of Two Compys: What Jurassic Park got right — and wrong — about dino anatomy

Bakker - Dino Geek JP 1

A piece of unapproved Ivy League art. Title: Podokesaurus holyokensis, Triassic/Jurassic Dinosaur, on the head of Michelangelo’s David. Material: Collage of Xerox images, clipped by scissors, Scotch taped together.  Date: March, 1964.  Artist: Robert Thomas Bakker, Yale freshman.

OMG I was such a dino-geek in college.

I had other interests — I was enraptured by sculpture and took the fabled freshman History of Art course. The collage shown here was taped together during the lectures on the Renaissance renewal of anatomically correct human form made famous by Greek sculptors. Last month, I found the collage in an old notebook, in the garage, under my copy of American Battleships, a Design History. (That’s for a future blog on the U.S.S. Texas.)

The tiny dinosaur is Podokesaurusat the time, one of two famous bantam-weight predators of the Late Triassic and earliest Jurassic, the first chapters in dinosaur history. I knew the critter well because it was dug from the red beds of the Great Triassic/Jurassic Valley. Those fossil-rich sandstones and shales filled a rift valley that extended from Nova Scotia to the Carolinas. The rift was as big as the East African Rift we see today.

Smack dab in the middle of the Triassic/Jurassic Valley was New Jersey, where I grew up. Not far north from my house were the Palisades and Granton Quarry, where Triassic flying reptiles had been discovered, plus long-snouted phytosaurs like our HMNS Smilosuchus, plus dino footprints.

The reason I applied to Yale was mostly because it had a museum chock full of red beds specimens. When I visited in 1963, Yale had a cast of the podokesaur skeleton on display — sadly, the original was destroyed by fire 50 years previously. Next to the cast was a lively life-sized sculpture, done by the Yale curator Richard Swann Lull.

“Nifty!” I thought. “Art and paleontology combined! This is the place for me.” The Yale museum was super hospitable to freshmen. I got a job cleaning a Triassic red beds skull — not a dino, but a bizarre plant-eating reptile, woodchuck-sized, with spikes coming out of the head like a tricked-out horned toad. These fellows must have lived in colonies. A bunch were dug from a small area in New Jersey. Podokesaurs surely chased these prickly morsels.

Late Triassic, New Jersey. A colony of vegetarian Hypsognathus emerges from their burrow. Maybe they had been hiding from podokesaurs, Maybe they had been watching Jersey favorite “The Sopranos” on HBO. Texas was host to a similar reptile. Extra points if you can find it in our Triassic mural.

Late Triassic, New Jersey. A colony of vegetarian Hypsognathus emerges from its burrow. Maybe they had been hiding from podokesaurs. Maybe they had been watching Jersey favorite The Sopranos on HBO. Texas was host to a similar reptile. Extra points if you can find it in our Triassic mural.

Freshman year also introduced me to the tradition of the “mixer” — parties where Yalies and young women from nearby colleges co-mingled. At a Mt. Holyoke mixer, I got an earful from female geology students who were steamed, justifiably, about gender bias. Old fogey Yale profs grumbled that “girls can’t lift heavy rocks [...] can’t do serious fossil work.” Podokesaurus was a counterargument. It was discovered in 1910 by none other than Dr. Mignon Talbot, who was chair of the geology department. Talbot did her Yale Ph.D. on sea-lilies, crinoids, relatives of starfish that were abundant in Devonian rocks of New York State (we have some fab Jurassic crinoids in our hall). Dr. Talbot went on to become president of the college.

The Wikipedia portrait of Dr. Talbot. The label must’ve been written by a Yale Professor.

The Wikipedia portrait of Dr. Talbot. The label must’ve been written by a Yale professor.

Even though, as college president, she out-ranked most of the Yale faculty of her time, they insisted on calling her “Miss Talbot instead ofDr. Talbot. Yeesh. In 1965, the Yale director of graduate studies told me “Bob, we shouldn’t give Ph.D.s to girls … they’ll just get married and have babies.” Double yeesh!

But he didn’t know how famous her dinosaur would yet become! Dr. Talbot’s dinosaur influenced Jurassic Park — yes, that little novel (series) turned super-franchise

In the article naming the beast, she noted that a similar-sized dino had just been excavated from the Late Triassic of Germany. It would be christened Pro-compsognathus” in belief that the renowned Compsognathus of the Late Jurassic might be a descendant (it isn’t). 

Since the one and only skeleton of the pro-compy is missing key parts, Dr. Talbot’s graceful Podokesaurus was used to fill in the blanks and give a general portrait of the fox-sized predators of the Late Triassic. Talbot’s creature gained more fame when it became the inspiration for an entire family, the Podokesauridae.

Later in the twentieth century more species were added to the podoke clan, including Coelophysis from New Mexico. The New York museums scored a mass grave of Coelophysis in the 1940s and 1950s: dozens of skeletons from adults two yards long to babies as small as Podokesaurus and Procompsognathus. 

Proud members of the Family Podokesauridae. Coeolphysis grew to seven feet long. Check out the pubis in these guys!!

Proud members of the Family Podokesauridae. Coeolphysis grew to seven feet long. Check out the pubis in these guys!

IMPORTANT WARNING! The Jurassic Park franchise uses two names for tiny Triassic dinos: “pro-compy” and “compy”. There might be confusion among the dino-laity.

The true Compsognathus is Late Jurassic, with kin in the Early Cretaceous, and it doesn’t have podoke family values. As we’ll see in a bit, Crichton clearly meant his tiny carnivores to be classic Late Triassic/Early Jurassic carnivores — and that means podokesaurs.

The podokes had a near-monopoly in the meat-eating role in the Late Triassic/Early Jurassic. They were not only small and mid-sized carnivores, equivalent to kit foxes, coyotes and wolves, but they became the movers and shakers in the apex predator role. Big species attained lengths of 22 feet and weights approaching a ton — bigger than the biggest land meat-eaters today (grizzly and polar bears). All podoke species had that graceful build of Dr. Talbot’s Podokesaurus: supple neck, long torso, and outstandingly elongated tail.

And, for those of you who are pelvis-literate, you’ll notice another design feature: The pubis bone was outstanding in the forward slant and length.

Podoke attack! A ten-foot long podokesaur predator menaces the thin-necked herbivore Anchisaurus. Early Jurassic, Massachussetts, somewhere near Amherst College. 

Podoke attack! A 10-foot long podokesaur predator menaces the thin-necked herbivore Anchisaurus. Early Jurassic, Massachussetts, somewhere near Amherst College.

For Jurassic Park fans, Procompsognathus rings a bell. In Michael Crichton’s novel, the first dino we get to know is tweensey (but deadly) — a species identified as a pro-compy. These blood-thirsty characters are fond of jumping into perambulators and biting the faces of juvenile humans. They move in gangs. Crichton was dead-on here. Tracks from the Triassic/Jurassic do document podoke-packs, small carnivores cavorting in groups.

Podoke dance floor? Slab of shale with a dozen small predators cavorting. 

Podoke dance floor? Slab of shale with a dozen small predators cavorting.

In the Jurassic Park movie, the pro-compys are unstoppable nasties who confront the gifted character actor, Wayne Knight (Newman) of Seinfeld fame. (Knight’s best known for portraying portly and disreputable men, but we should remember that he was a dashing romantic lead in Third Rock from the Sun.)

In Jurassic Park, Knight’s character learns a lesson — the hard way. At first, he insults the pro-compys and tries to scare them away. Then they flash their threat-collars, a device cribbed from the Australian Frilled-Lizard. Then they hurl loogies of what seems to be venomous schmaltz. Nice scene. Scary.

However, dino-nerds: watch out. There are no bones in the lizard collar so preservation in a skeleton would be unlikely. Plus, threat collars are unknown among the many dinos now represented by fossils with skin. 

Plus, plus, no dino could spit. Spitting requires complex lip and face muscles of the sort a trombonist must have (didja know I was first-trombonist in the school band?). Reptiles can’t spit, birds can’t spit. Fossil dino faces show that the big, complicated lips just weren’t there.

Spitting cobras cheat. They don’t really spit. They have mouth muscles that squeeze the poison gland so the venom comes squirting out through the hollow fangs. Clever, but not a genuine spit.

Crichton used his dinos carefully. He fills Jurassic Park and Lost World novels with a lovely time-safari through the Mesozoic. He begins with the pro-compy, from the earliest slice of dino-time, about 210 million years ago. The long-necked brachiosaurs and stegos filled out the later Jurassic, some 145 million years ago. You could add a true Compsognathus here if you like. For the Early Cretaceous, 110 million years ago, we are given Deinonychus antirrhopus (labeled Velociraptor but actually Deinonychus). Triceratops, T. rex and the advanced ostrich-dinos fill out the last slice of Cretaceous, the Lancian Age, 66 million years ago. You can teach an entire paleo course with this fine selection of fossils. 

Remember, in the books and movies the label “pro-compy” and “compy” is synonymous with the podokesaurs. Crichton did not intend his Triassic dino to be a Compsognathus, the Late Jurassic animal quite different in body plan from the podokesaurs. Here’s where dilophosaurs come in.

Dilophosaurus, sensu stricto, is a Southwest Early Jurassic apex meat-eater — a big brother of Coelophysis and Podokesaurus. The first specimens were announced by the Berkeley museum in the 1950s. Size: near maximum for the podoke family, nearly 2,000 pounds soaking wet. Our Chinese colleagues excavated a super diloph of the same body mass. In each and every bony bump, the dilophosaur is built to the same basic plan used for Coelophysis, et al. Big difference, besides size, is the side-by-side bone crests on the head.

The Berkeley diloph. Black-n-white foto shows first restoration of head without crests. Color snapshot shows the crests added. Michelangelo’s David in for scale. Do note that this is a biggish predatory dino. 

The Berkeley diloph. Black and white photo shows first restoration of head without crests. Color snapshot shows the crests added. Michelangelo’s David in for scale. Do note that this is a biggish predatory dino.

In the books, Crichton does not describe any head ornaments for his pro-compys. The movie, on the other hand, gives the little fellows side-by-side crests, perfect miniatures of what true dilophs have. I go to screenings of the JP franchise every chance I get (“JP” is what we insiders call Jurassic Park). When I saw the 3D version on the HMNS Giant Screen, I was treated to massive vibrations that punctuated the scary parts. 

“Dilophosaurus … DILOPHOSAURUS!” shouted the five-year-old sitting behind me. He was kicking the back of my seat with unconstrained enthusiasm. Can’t blame the kid. He had his plastic diloph in his lap, evidently a cherished pet and quite accurate in most anatomical details (neck and ankle too long, too skinny). The extreme close-ups of the pro-compy head on the screen did look diloph-y. But … the size was as wrong as wrong can be and still stay within the podoke family.

Plastic dilophosaur, by Safari Ltd. About nine bucks at the museum gift shop, with your member discount.

Plastic dilophosaur, by Safari Ltd. About $9 at the Museum Store, with your member discount.

I was tempted to turn around and issue a correction: “Hey kid, that dino is a hundred times too small …” But I restrained myself. I estimated that the leader of the movie pro-compy pack was no more than 15 pounds, Boston Terrier-sized. With head crests, size matters. Small podokes don’t have much in the way of cranial protuberances. All the big crests are on big heads attached to big bodies.

Want to be a podkesaur? You must get a nose-notch. Coelophysis here has one.

Want to be a podokesaur? You must get a nose-notch. Coelophysis here has one.

And … there was something more, something missing from the schnoz in the movie compy. “No nose notch …” I said to myself. “Those guys in the movie have no nose notch … so … they aren’t members of the Family Podokesauridae!”

Notches below the hole for the nostril are a big deal in dinos and dino-kin. Land Croc-oids of the Triassic, second cousins of dinosaurs, usually are notched. But strong notches are rare amongst the carnivorous dinosaurians. T. rex is notch-less. So is Allosaurus and all the myriad raptors, from Micro-raptor to Meso-raptor to Mega-raptor. The bona fide Compsognthus is notch-less. The podoke family is the most consistently notched. Enjoy my own diagram of the Harvard skull from Coelophysis above. Please stare at the nose. There’s a notch here. Dilophosaurus has an even more emphatic notch.

No notch = no podokesaurid. Simple as that.

What about that long, slanty pubis, another hallmark of the podoke family? Study the movie dino as long as you like. You will find no unambiguous evidence of long, slanty pubic bones. None.

My conclusion: the movie artists did a great job with the pro-compys. They cobbled together a frightening chimaera from a bunch of critters, some lizards, some small meat-eating dinos, some big ones. These little dinos are the most imaginative, most mixed-up of all the JP creations. So enjoy them! But you cannot use the movie pro-compys to teach a lesson in dilophosaurs or any dilophosaur kin. The movie “compy/pro-compy” is NOT a crested podokesaur.

* Recently, some paleontologists have insisted using the name Family Coelophysidae to replace Podokesauridae, because we have so many skeletons of Coelophysis. These folks are well-meaning but, ahem, I am a Yalie and so I am sworn to defend the honor of Mt. Holyoke College and all its faculty and graduates. And its presidents. And its dinosaurs.

The guts stop here: Delve deeper into dinosaurian intestines with Dr. Bakker

Attention all Dino-Nerds! Put Your Anatomical Expertise to Work. Prestigious Careers Await in the Field of Gastroenterology.*”

Bakker Dino Guts 1

Where the guts fit in a T. rex. The pubic bone (yellow) sticks down and won’t let the intestines expand behind the hip socket.

Often, I get approached by parents who fret over their dino-fixated kid. “You gotta help us, Doc. All she wants to do is read about fossils. Will she ever find a respectable career in the real world?”

I can reassure Mom and Dad that studying dino anatomy can lead to well-paid and honorable occupations — for instance, as a professor of anatomy or a foot surgeon or a knee specialist. Or a gastroenterologist. Being a gut doctor is becoming especially attractive now because aging yuppies are suffering from decades of intestinal abuse from spicy nachos and a misplaced reliance on gluten-free pizza.

So, adults, encourage the children to delve deeply into the dinosaurian intestines. It’s fun. It’s educational. It might pay off — big time.

T. rex was a gut-less wonder

The first step toward a visceral understanding of dinos is to face the fact that T. rex was a gut-less wonder. Consider the rexian body cavity. The space available for guts is severely limited. That’s because the intestines must stop at the pubic bone, the big prong that points straight down from the hip socket. It’s inviolable anatomical law: No intestines can be behind the pubis!

In a rex, that means all the guts are in front of the hip socket and there just isn’t a lot of room here. You might argue that rexes were forced to be pure carnivores because they needed high protein food that could be digested with a minimum weight of gastric equipment.

(Vegan advice: A gentle admonition to all my vegan friends in Boulder, Colorado: High fiber plant food demands big, complicated gut compartments, a series of vats where the fodder is soaked and softened, worked upon by microbes that secrete the enzymes needed to break down fiber. That explains why Herefords and zebras, which are consummate digesters of grass, have naturally rotund tummies. Contrary to widespread myths, we humans, when we first evolved, were not adapted to high fiber, animal-free diets. When Australopithecus evolved into our genus Homo, the size of the gut shrank dramatically. So we had to specialize in protein-rich food, such as eggs, baby birds, grubs, turtles, bunnies and antelope carcasses scavenged from unwary saber-tooth tigers — plus, of course, nutritious fruits and nuts and tasty tubers excavated with digging sticks and roasted over the fire. Fire was domesticated at about the time our guts diminished in volume. Cooking releases food value otherwise unobtainable with our small-size intestines. Today, a modern human can indeed survive on a plant-based diet but you choose your veggies carefully. And cook ‘em.)

Bakker Dino Guts 2

Fowl guts.

Chickens that don’t fall over

Now that we’ve learned the basic laws of gut size, we are ready to unlock the mystery of the balanced chicken. You’ll remember from the previous post that barnyard fowl have exquisite balance on just two legs, despite the lack of a heavy tail.

Here’s another fowl mystery: Chickens have formidable digestion. They can extract food value out of raw grains and plant fiber far better than we humans can. The secrets to balance and digestion are one in the same — the gut-wrenching development of the pubic bone. When an embryonic bird in its egg is just beginning to develop a pelvic skeleton, the pubis points down, sorta like an adult T. rex pubis does. But when the chick hatches, the pubis has rotated completely around so it points backward and the guts expand behind the thigh.

Brilliant! The pubic re-alignment has doubled the potential room for intestines. And all that new weight of intestines is behind the hips, and therefore, confers perfect balance without any sort of ponderous tail.

Pubic-wrenching is a splendid osteological trick. Some dinosaurs did exactly the same thing. Stroll past our fine duckbill skeletons. Fix your gaze on the pubic bone. It’s rotated backward, just like a four-ton version of the barnyard fowl.

The duckbills go even further in gut expansion than do most birds. The pubis and ischium (the other lower hip bones) are so extended toward the rear that the guts gain another yard or two of length and allow another couple of chambers for microbial action on the food. All those extra digestive vats would let the duckbill G.I. tract break down even the toughest, most fibrous vegetables.

Duckbills win the award for longest gut tract of any dinosaur. And, probably, had the least constipation problems.

There’s a word every dino-nerd learns in the first grade: “ornithischians”. The simple meaning is “dinos with bird-style hips,” and that denotes the many species, like duckbills, that have undergone gut-wrenching. Stegosaurs wrenched their pubes, as did Triceratops.

Make a game of it! Go through our Fossil Hall with the children seeing how many different skeletons show the backwardly-bent pubes. Make the whole family pubo-literate!

Bakker Dino Guts 3

Before and after gut-wrenching experience: Top duckbill dinosaur shows how intestines would be limited if the animal had the primitive, vertical pubis. Bottom duckbill shows the real bent-back pubis and ischium.

When I skulk around our tour guides as they talk to school groups, my rib cage swells with pride. Our docents are the best! So I want to add an advanced bit of pubic-lore here. Stegosaurs and many other gut-wrenched herbivores do something tricky, pubis-wise.

After they evolved the backward-pointing pubis, these dinosaurs grew new pubic prongs — one on each side of the rib cage — that pointed forward and outward. This new set of prongs didn’t change the gut layout at all. The new prong lies outside the body cavity. The guts lay between the left and right new prongs.

What good did the new prong do? A stout muscle probably attached to it and ran back to the thigh to help swing the hind leg forward. If your child is considering med school, tell her that this muscle is what we call in humans the “psoas.

Bakker Dino Guts 4

Colorado State dino, Stegosaurus, showing the new prong of the pubis that points forward. Don’t confuse it with the true pubis!

And now, the ultimate Darwinian inquiry into gut-wrenching, the question that earns me sour stares from all my creationist relatives (37 full cousins on one side, 97% creationists)…

Here’s the query: When did pubic-twisting happen in the evolution of birds?

The chicken diagram I used earlier works pretty good for all modern day birds — every single one of the 10,000 species. From hummingbirds to ostriches, today’s avian species have the strongly wrenched pubic shaft and the attendant elongation of all things intestinal. No modern bird has the vertical pubis and short gut of a T. rex.

Bakker Dino Guts 5

Diagram of Archaeopteryx from Heilmann’s 1926 book “Origin of Birds”, modified by me in 1958. Heilmann explained the mix of bird and pre-bird features.

Archaeopteryx surprises

When first discovered in the 1860s, the Late Jurassic Archaeopteryx was an evolutionary celebrity, a missing link combining perfectly formed avian designs with archaic dinosaurian features. The first “Archie” skeleton excavated was jumbled but it certainly looked like the long, thin pubic bone was bent back in standard bird configuration. “Archie” also possessed another definitive bird device — the lagoonal, limestone-preserved imprints of fully-formed flight feathers.

Some dino characteristics were retained too: sharp little teeth, curved claws on the fingers, separate bones in the wrist (modern birds fuse up the individual bony units), and a long bony tail. The Archie was dubbed “Ur-Vogel” in German, an event which solidified the critter’s place in nature.

“Proof that creationism is wrong and Darwin is right!” shouted many an agnostic in 1868. In fact, the chap who coined the term “agnostic,” Thomas Henry Huxley, led the charge in proclaiming birds as descendants of wee dinos. Huxley’s favorite dinosaurian was Compsognathus, the original “Chicken-Dino,” a Late Jurassic carnivore extracted from the very same lagoonal rock that produced Archaeopteryx.

The Compy skeleton was cute as a button — so small that Huxley could imagine it perched on his shoulder during debates about Darwinism. When I began reading dinosaur books in the 1950s, the Compy was still the tweensiest dino known and several kids’ stories had a pet Compy following a second grader to school.

That image was just too cutesy-pootsy, too Disney, and the Compsognathus needed a makeover to give the species gravitas. The Jurassic Park franchise of the 1980s did just that. In the first Jurassic Park book, Compys are turd-eating pack-hunters that would jump up into a crib in a children’s hospital to bite off the kid’s nose and cheeks and rest of the face. That scene definitely stripped away the excess cutesy.

In the movie Jurassic Park, the Compys were upgraded to frilled little monsters that spat narcotizing pea-soup in the face of characters before biting off their noses, cheeks and rest of their faces. That scene ripped away the excess pootsy.

Movie villains can seem especially evil when they begin as pint-sized plush toys and then metamorphose into killers. Remember Gremlins and Chucky? (Maybe the writers of Jurassic Park scripts were trying to do to Compys what Miley Cyrus did for herself — take an adorable little star and remake the image so it seems more adult and more formidable. I believe that, when you go slow-motion through the Jurassic Park movie, you can see some of the Compys twerking.)

(Be advised: Jurassic Park books and film mix and match parts from three different dinos: (1) The true Compsognathus, beloved of agnostics; (2) The enigmatic pro-compsognathids known only from incomplete Triassic specimens; and (3) The distant compy cousin, the hefty 20-footer, Dilophosaurus, from the Early Jurassic. None were poisonous. None could spit. But recent discoveries from China reveal a raptor with teeth grooved like a gila monster’s — that means poison glands dripped venom down the grooves into wounds. Cool.)

Bakker Dino Guts 6In all three real dinos that inspired the Jurassic Park Compys, the pubis pointed downward and forward, the primitive configuration for carnivorous dinos and retained in our Texas Coelophysis. No gut expansion here.

Bakker Dino Guts 7

Bambiraptor, a little raptor-type dinosaur from the Late Cretaceous. Diagram done for Dr. David Burnham and me when Bambiraptor was named. Note that the pubis is bent back just a bit.

In the 1970s, Yale’s John Ostrom rediscovered Huxley’s insights. He used the recently discovered Deinonychus and its kin to prove that raptor-type dinos had hands, feet and a tail nearly identical to what Archaeopteryx possessed. But raptors still had primitive pubic bones that were bent back just a little bit. See the raptor-pubes for yourself in our “Julie-raptor” skeleton on display at HMNS or in the Bambiraptor skeleton in the lab (come by and take a look).

So, because of its superior pubic wrenching, Archaeopteryx was entitled to be hailed as more advanced than most raptors.

That made us all happy because we could make a nifty evolutionary scenario — an early raptor-like dino, a Jurassic version of Deinonychus, evolved into an Archaeopteryx-oid and then the Archie-oid evolved into a modern bird in the Early Cretaceous. Take that, my creationist-cousins!

(By the way, don’t let TV’s South Park mislead you; the plural of “pubis” is “pubes,” and it’s pronounced “pew-bays” and not “pewbs.”)

But then came the inevitable Oops Moment. That happens whenever we get too cocky.

Our friends at the Thermopolis Dinosaur Center in central Wyoming announced they had obtained a near perfect Archaeopteryx in 2006. I rushed up to ogle it, armed with a zillion photos of all the other Archie specimens. I stared at the pubes.

The new specimen and the other best specimens showed that the simple pelvic scenario was wrong. The real, undistorted Archaeopteryx pubis pointed straight down. No backward wrenching at all. In other words, Archies had no gut expansion whatever. The Ur-Vogel was no more advanced in this one key hip feature than an allosaur or a tyrannosaur.

Bakker Dino Guts 8

A very accurate diagram of Archaeopteryx, drawn by the magisterial paleontologist Peter Wellnhofer, who is the all-time expert on Jurassic pterosaurs and birds. Note the disturbingly vertical pubis.

Dang, dang, double dang

In this one famous feature, the backward wrenching of the pubis, Archaeopteryx turns out to be less like a modern bird than Bambiraptor or Deinonychus. Gosh … nearly every ornithischian dinosaur has more advanced pubic positions than does an Archaeopteryx.

We should’ve known. Evolution hardly ever goes in a neat, straight line. The origin of birds didn’t come about as one undivided line of dinos that gets better and better, more and more like a chicken, from the Triassic through the Jurassic and then into the Cretaceous. Darwinian family trees are much more complicated and much more confusing — more like tangled blackberry bushes, full of short branches going off in all directions. There are side branches and side branches coming off the side branches.

Archaeopteryx itself couldn’t survive by being a mere ancestor; it had to fit into its local environment; it had to be adapted to its immediate surroundings. The short gut and un-wrenched pelvis worked fine. A cluster of raptor-like dinos, with minor variations in pubic slant, shared the basic Archaeopteryx blueprint — and they too thrived for millions of generations. Even in the latest part of the Cretaceous, un-wrenched guts with vertical pubes contributed to the success of little Bambiraptor type predators.

Finally, after the Cretaceous ended, all the raptor-type dinos and all the birds with vertical pubes were extinct. Now, in today’s habitats all over the world, no bird or bird-like animal operates with the un-wrenched gut. Why? Did the short gut prove inadequate somehow in the long run? Could be. But we must remember that short-gutted birds and raptor-like dinos had done very well since the Mid Jurassic to Late Cretaceous, and that’s a full 100 million years. It’s not totally true, the old adage, “No guts, no glory.”

* It’s traditional for paleontologists to teach anatomy to pre-meds. I did that for years: at Harvard, then at Johns Hopkins. Thomas Henry Huxley, who worked out relations between little dinos and birds in the 1860s, also taught courses in basic dissection. It’s even more socially acceptable to be a genuine medical doctor who also digs fossils.

True story, not a Seinfeld episode: When I visit my mom at the retirement home, she introduces me as “my son, Dr. Bakker.” All the octogenarian ladies lean forward smiling. Then, politely, they begin to ask specific questions about certain medical conditions. Mom whispers, “He’s not a real doctor…” and all the ladies lean back with a slight curl of disapproval in their smiles.

Nota bene: The new book Ten Thousand Birds, (Princeton University Press), is wicked good — best ever done on our feathered species. Beautifully written. Everyone should get a copy.

Sea Rex 3D swims into IMAX!

Explore an amazing underwater universe inhabited by larger-than-life creatures that ruled the oceans millions of years ago in Sea Rex 3D – now showing in HMNS IMAX!.

Mosasaurus hoffmannii skeleton on display at the
Maastricht Natural History Museum,
The Netherlands

Guided by Georges Cuvier, considered by many to be the father of paleontology, viewers learn about predators such as the ichthyosaur, plesiosaur, and mosasaur. These ancient creatures could grow up to 50 feet and could weigh as much as 15 tons.

Learn about the Triassic, Jurassic, and Cretaceous eras and how life evolved in the deep oceans of Earth. See a mosasaur battle the Great White Shark’s ancestor and witness the mating habits of the plesiosaur.

You’re going to love the film’s time line of the history of the Earth, showing the evolution of the first single cell organisms to the mammals that evolved and began to walk on land. What I found fascinating is the amount of time each of the dinosaurs ruled the world in comparison to humans. Dinosaurs walked the earth for over 160 million years, while humans have only been around for about 200,000 years comparatively.

Evidence of giant marine predators were first discovered in a mine shaft in the Dutch city of Maastricht in 1770, when the partial skull of a Mosasaurus hoffmannii was uncovered. Sea Rex 3D takes you on a journey from the creation of earth until the meteor that killed off 95% of life 65 million years ago. Don’t miss this incredible story about our planet’s history and the monsters that ruled the sea for over 120 million years.

Can’t see the video? Click here.

Sea Rex 3D is now showing in the Wortham IMAX Theater. See show times on our Film Schedule.

The Ghost Sharks of The Jurassic

Fish Pieced Together by Committee

Our HMNS at Sugar land exhibition on Archaeopteryx is festooned with splendid finny fossils, the ichthyological gems of the Late Jurassic. Some of the Jurassic fish were new comers, recently evolved clans that were poised to conquer the watery ecosystem. Teleosts are one such progressive group.  But there are Jurassic living fossils. These are old, old clans that had evolved a hundred million years before the Jurassic, or more. And these groups had stalled out, in evolutionary terms, changing little.

Chimaeras, the “ghost sharks,” are the most exotic of the Jurassic living fossils. The label “Chimaera” evokes the mythological critter that was put together with spare parts from many species. The real chimaera fish do seem to be constructed that way. The huge eyes and  nibbling snout look like a rabbit’s, inspiring the label “Rabbit Fish.” The front fins are huge, resembling those of a butterfly-fish. The tail is long and thin, like a rodent’s – hence another nickname “Rat-Fish.”

In fact, Chimaeras are distant cousins of sharks and rays.

Chimaeras were already an antique group by the Jurassic, with an origin going back almost to 400 million years ago. The body form had been standardized by the Coal Age, 330 million years ago. The key feeding feature was the solid, strong, stiff heads. Teleost fish gained success by loosening up face and jaw bones, so the mouth could expand. Chimaera evolution went the other way. Their skulls were solidly knit together, with jaws, face and braincase units braced against each other.

Global paleogeographic reconstruction of the Earth in the late Carboniferous (“Pennsylvanian”)
period 300 million years ago.
Creative Commons License photo credit: Dr. Ron Blakey

The solid chimaera skull was co-evolved with flat, thick teeth that could crunch and crack crabs, clams and all sorts of other hard-shelled teeth. In other words, the chimaera was the fishy equivalent of a sea-otter. For protection, chimaeras were outfitted with a sharp, tall spine at the front of their dorsal fin.

Even though they hadn’t upgraded their adaptive equipment for a long time, Jurassic chimaeras continued to succeed as  bottom-hunting predators of shellfish. And they kept on going, and going, and going….

….surviving through Period after Period. They’re still around today. In their anatomy, the modern chimaeras are barely different from the Jurassic species. But habitats have changed dramatically. Jurassic chimeras thrived in shallow water of the Solnhofen lagoons and reefs. And the earlier chimaeras too were mostly inhabitants of the shallows. Most species alive now are  deep-water specialists. The same slide from shallow to deep water happened to one group of bony fish, the coelacanths.

That’s a general evolutionary principle: fish that ranged through upper waters in the past tend to get restricted to the deep today.  Why? Maybe new predators and competitors tend to evolve first in shallow water. And thus shallow water becomes the most dangerous place for old clans who don’t evolve fast. Going deep may free the old-style fish from many of the exuberant new clans.

Maybe….

Learn more about evolution by visiting our unique collection of fossils in Archaeopteryx: Icon of Evolution, now on display at HMNS at Sugar Land.