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.

Cracking the coelacanth code: Living version of HMNS fossil has genome sequenced

The coelacanth — a “living fossil” believed to have hardly changed over the last 300 million years — has finally had its genome sequenced by European researchers.

courtesy of wiki media
The deep-sea fish was the inspiration for the famous 1954 film Creature from the Black Lagoon and is well-represented here at HMNS, where we have three examples on display: a Devonian fossil, a Cretaceous specimen and a model like the one sequenced.

Researchers sorted through nearly 3 billion DNA bases to conclude that the coelacanth’s four fleshy fins were likely the early predecessors of limbs.

Although the coealcanth is related to early tetrapods — the first creatures to make the transition from the ocean to land — a comparison of the coelacanth genome with the DNA profiles of lungfish and other modern land-based animals led scientists to conclude that lungfish were the closer relative.

Coelacanths have been notoriously difficult to study, having been assumed extinct until an African fisherman caught the living fossil in 1938. Since then, only a few hundred specimens have been found.

Continue the investigation yourself at our Morian Hall of Paleontology, and see why this mysterious fish has kept researchers rapt for so long.

Your questions, answered: Do we know when chimaeras shifted to deep-water habitats?

Earlier this month we received a question on one of our past posts, The Ghost Sharks of the Jurassic, asking:

“Do we know when these chimaeras shifted to deep-water habitats? If predation and, in particular, the evolution and diversification of predatory species prompted their geographic transition, at what point would a sort of critical level have been reached to drive them into the deep? How many predators are too many?”

Why do “living fossils of the deep sea” so often represent lingering survivors of groups that long ago flourished in shallow water?

 
Rabbitfish

Examples: Rabbitfish (aka chimaeras), Coelacanths, Goblin Sharks, Giant Squid.

Excellent question – one that keeps evolutionary biologists awake at 2 a.m.

First thing: we never know when a clan of species invades deep water. This is why:

Sediments deposited on top of oceanic crust in deep-water – thousands of feet deep – rarely come to the surface where the layers can be seen by fossil-hunting paleontologists. Mud does form at the bottom of deep seas and fossils do form here. But such deep specimens have a low chance of being found by us.

Deep sea bottom mud is raised above sea level when continents collide and abyssal sediment is squeezed up and thrust across slabs of continental crust. There are narrow zones of such squeezed sediments – for example, in the Taconic Mountains of New York State. Here are slices of deep crust and sediment with deep-water trilobites. However, very few vertebrate and squid fossils are known from squeezed deposits.

Medium-deep sediment, up to 200 meters deep,  do form in the bottom of “epi-continental seas” like the famous  “Cretaceous Ocean of Kansas” that covered much of the central areas of North America. Such epi-continental seas  do drain away, and the bottom sediment becomes lifted hundreds or thousands of feet, so wind and water can erode valleys into the rock layers, exposing fossils. Epi-continental sea bottoms have given us 90% of our marine vertebrate and cephalopod fossils.

Coelacanth fossils are common in shallow-water and medium-deep sediments beginning in the Early Devonian, over 400 million years ago. From then on, coelacanths remain widespread and often common. Were they in deep water too? We don’t know – we don’t have enough deep sediment exposed for study.

Abruptly, coelacanths disappear from epi-continental sea deposits in the Late Cretaceous. Naturally, we thought they were extinct. But then the fish show up alive and well, hanging around at 130 meters to 700 meters.

Ditto for the Goblin Shark: common as a fossil along New Jersey in shallow sediment but now restricted to much deeper waters. Ditto for the giant squid, who left their shells in the Cretaceous epi-continental sea sediment but now prefer deeper water.

Goblin Shark

Is there a common explanation for all the survivors in deep waters?

The most popular theory is: 1) Most new types of fish and cephalopods first evolve in shallow water. 2) It takes time for evolution to modify a fish or cephalopod so the beast can survive at 200m + depths. So the early coelacanths couldn’t colonize the great depths for tens of millions of years. As more and more clans of fish evolved in shallow water, some began their adaptive descent too – but the coelacanth had a head start. Being fully adapted to great depth already may have protected the fish from predators and competitors who are behind in the degree of their transition.

There are holes in the theory. Coelacanths do have predators – they show up in shark stomachs. They must have competitors too – teleost fish with more complex jaws.

Deep Sea Refuges continue to irritate our neat little hypotheses.

WAnt more? See the past post on ghost sharks and full comment.

100 Years – 100 Objects: Life Through Time Mural

The Houston Museum of Natural Science was founded in 1909 - meaning that the curators of the Houston Museum of Natural Science have been collecting and preserving natural and cultural treasures for a hundred years now. For this yearlong series, our current curators have chosen one hundred exceptional objects from the Museum’s immense storehouse of specimens and artifacts—one for each year of our history. Check back here frequently to learn more about this diverse selection of behind-the-scenes curiosities—we will post the image and description of a new object every few days.

This description is from David Temple, the museum’s curator of paleontology. He’s chosen a selection of objects that represent the most fascinating fossils in the Museum’s collections, that we’ll be sharing here – and at 100.hmns.org/ – throughout the year.

life through time muralTimelines are an important element to telling a story through exhibits. At the Houston Museum of Natural Science, early life on Earth is recreated in a linear timeline, with the fossils themselves as the “stops.” The time represented is collectively grouped as the Paleozoic period, and accounts for around 300 million years of the history of life.

The fossils displayed on the wall form the stops on the time line, grouped by famous localities that historically defined the sub eras: Pre-Cambrian, Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. This is appropriate as, prior the development of technology that allows paleontologists  to compute absolute dates, the divisions between the geologic periods were defined by the fossils present in geologic layers. At first glance, the fossils in the case may appear similar, but they are very different, and come from many of the type localities that created the boundaries.

To bring this timeline to life, a vibrant visual motif was created. Mounted behind the fossils is a brightly lit graphic that unfreezes the animals from their rock prisons and remembers them as best we can, alive and in their natural environments. This motif came from an original oil painting commissioned by the Houston Museum of Natural Science. The Paleozoic diptych, painted by acclaimed paleontology artist William Stout, is titled “Life Before the Dinosaurs.” The original oils have never been exhibited publicly, but grace the walls of a conference room.

Wander among prehistoric beasts in the Paleontology Hall, a permanent exhibition at the Houston Museum of Natural Science.

You can see more images of this fascinating artifact – as well as the others we’ve posted so far this year – in the 100 Objects section at 100.hmns.org.