A Q&A to the Diplodocus degree: HMNS skeletons still inspire after 110 years

Editor’s Note: Sometimes, you ask us questions on Facebook or Twitter that require a bit more than just a pithy response. So .. we wrangle the experts to get to the heart of the matter for you. You’re welcome.

Q: A write-up on another Diplodocus says that the forelimbs and hands on all the Carnegie casts are all based on a Diplodocus specimen from the Houston Museum of Natural Science. Is this the one known as “Dipsy,” first mounted in 1975? Or a different one? There’s a reference online to one excavated in 1902, but again, I don’t know if this is the same specimen. -Andrew Armstrong

bob.bakkerA: Yes indeed, our Dipsy has unusually fine feet.

Our skeleton is a composite of the two famous ones dug by Utterback near Hole in the Wall, Red Fork of the Powder River, Wyoming, way back in 1902-1903. Butch Cassidy and the Sundance Kid had their secret camp not far away. The Dipsy Duo skeletons were originally numbered as 307 and 662 in the Carnegie Museum catalog.

Not only are the forefeet and hind feet quite splendid, but the braincase — the biggest, most complicated unit in the entire skull — is still the most perfect one for all diplodocines. Matt Mossbrucker at the Morrison Museum and I are publishing a paper using the Dipsy Duo to re-think how long-necked dinos used their heads.

Here’s a close-up of our braincase, set on the first two neck vertebrae:

jm_dippy_carn_art_bcase-axis

And a shot of the excellent Denver skeleton with our entire neck and head, so you can see the proportions of skull and cervical vertebrae:

jm_dippy_carn_grey_neck_dnvr

Stay tuned: the Dipsy Duo head and neck are about to start a Diplodocus Renaissance.

-Dr. Bob Bakker

Nota bene: As of September 2013, our darling Dipsy the Diplodocus has been de-installed and is currently on vacation in Black Hills, being cleaned and repositioned. She will return to us and take up permanent residence in our Morian Hall of Paleontology in the next year or so.

Dinosaurs in three dimensions: See Jurassic Park 3D on Houston’s biggest screen — complete with a Jurassic Paleo Hall tour

It’s the cult classic that launched a thousand fascinations with fossils. Influenced a generation of dinosaur devotees. Made you forever fear wilderness toilets, whether stranded on a prehistoric amusement park/island or just camping in Pedernales.

jurassicpark3dNow Jurassic Park is back in 3D, and this, well, this you’ve got to see. And where else than at HMNS’ Giant Screen Theatre, also known as the single largest screen in town?

So perhaps you already know we have an expansive screen. But need we mention our new, not-even-a-year-old, monstrous Morian Hall of Paleontology? Yeah. It’s only what the Huffington Post called one of the top dinosaur exhibits in the entire country. No big deal.

But to add to our Jurassic fierceness, our docents are guiding special <i>Jurassic</i> tours of that new Paleo Hall — spotlighting the real specimens featured in the film and separating scientific fact from fiction. Oh, yeaaaaah, we did.

For more information on our guided tours, call the Box Office at 713-639-4629 or click here to reserve your Jurassic Park 3D tickets!

Bakker blogs: Murder by hickey — or a dinner date with a meat head

We’ve been pondering  the problem of Dimetrodon-on-Dimetrodon violence. It’s a Red Beds tragedy; fin-back reptiles were nibbling each other’s brain bones and gouging each others’ cheeks.

But now, maybe, we have some evidence for the softer side of fin-backs: hickeys and love-bites.

Here’s a scientifically precise reconstruction of one fin-back smooching another on the back of the neck, sort of like the cover for a Permian romance novel: Fifty Shades of Red (Beds).

Murder by hickey: Dr. Bob explores another side of Dimetrodon-on-Dimetrodon violence in the latest Bakker blog

Neck-nibbling is quite the thing among living species of predators, both large and small. Cats do it. Go to Animal Planet and see male lions grabbing the lioness by the nape.  Or come visit our Seymour digs in north Texas and meet “Elton,” the male Mountain-Boomer Lizard. Male Mountain Boomers, aka “collared lizards,” are the brightest lizards in all of the Lone Star State.  Not “bright” as in “smart,” but as in wearing “fabulous iridescent blues and pinks and yellows in the mating season.” Elton stakes out a wide, flat area in our quarry where he struts his stuff, doing Marine-style push-ups to attract females and frighten away younger males. Every spring he succeeds in enticing a healthy female, almost as muscular and buff as he is.

Here’s a portrait of Elton, snapped by David Temple, Curator and Herpeto-photographer extraordinaire.

Murder by hickey: Dr. Bob explores another side of Dimetrodon-on-Dimetrodon violence in the latest Bakker blog

(Warning: If you keep Boomers in captivity, never have two males together in a small cage. They’ll beat the coprolites out of each other. The same warning often applies to keeping two curators together.)

Actual Boomer mating includes neck-grabbing. Elton has an extraordinarily wide forehead housing mighty jaw muscles, so the love-nibble has force behind it. If she’s willing, the female displays a hunkered-down posture and shows off her red dots. Therefore, when the female Boomer signals “Bite me!” it’s in fact a “Come hither!” message.

Here’s a fine snap of a female Boomer, from Mike Cong Wild Photography.

Murder by hickey: Dr. Bob explores another side of Dimetrodon-on-Dimetrodon violence in the latest Bakker blog

Elton does NOT view us humans as a higher species. He’ll race to where we’re digging under the shade of a tarp and give us the hairy eyeball, lizard-style, cocking his head right and left. Then out he goes to ascend his viewing stand, a foot-tall sandstone block 20 feet away.  I think he’s checking us out to make sure we are not competition for his favorite lizard-love.

Given such behavior by Elton, we expect that our 400-pound Dimetrodons engaged in some sort of gnathic-cervical love-grabbing. Do we have petrified evidence? You bet. Here’s a cervical vertebra number two, the big bone right behind the head. It belongs to a full grown  D. loomisi, a species nicknamed the “Keira Knightly Finback” because of the excessively long, slender neck. The arrow points to a bite — a  powerful nibble that actually removed a piece of bone.

Murder by hickey: Dr. Bob explores another side of Dimetrodon-on-Dimetrodon violence in the latest Bakker blog

But that’s a bit too big of an ouch. There would be thick muscles running from the vertebra to the back of the skull that flex the head up and down, side to side, and twist the head around. This bite would have gone right through the thick part of the muscles, leading to massive trauma, blood loss and death.

Murder by hickey!

Check out this diagram: On the right you’ll see some of the massive and meaty muscles that are located around the head and neck.

Murder by hickey: Dr. Bob explores another side of Dimetrodon-on-Dimetrodon violence in the latest Bakker blog

It was a sad day when we realized that our love nibble was instead hard evidence of cannibalism. But the head-neck bites also prove something elegant and marvelous about Dimetrodons. We mammals are, supposedly, the Highest Class. We have the most advanced, most efficient anatomical tools for cutting up our food and digesting it quickly. We are far better than the cold-blooded class Reptilia, or so the textbooks say.

Cold-blooded reptiles today do seem sloppy and inefficient. Nile crocodiles and komodo dragon lizards kill zebra, wildebeest and goats — but once their prey is dead, their table manners are primitive. The big reptiles bite their prey anywhere and everywhere, chomping down on bony snouts and chins where there’s not much meat.

Mammal top predators display far greater precision. The tiger examines his prey carefully before removing bite-sized pieces off the meaty zones. The rear teeth slice meat as efficiently as your neighborhood butcher making prosciutto.

You can do this experiment  at home: buy some delicious Texas beef jerky and present a big piece to your hungry dog (or your friend’s). The pup will position the jerky between its rear teeth and slice, slice, slice, GULP. The quick slicing action comes from special features of those rear teeth.

Scrutinize these photos of a wolverine. See the big rear teeth?  When the wolverine bites meat, the upper rear tooth slides against the lower tooth, and the teeth hone each other like metal shears. That’s why mammal meat-eaters can cut even tough meat and tendons swiftly.

Murder by hickey: Dr. Bob explores another side of Dimetrodon-on-Dimetrodon violence in the latest Bakker blog

Fossil predator lairs from the Age of Mammals show that these precision-slicers are old adaptations. When we excavate prey carcasses left by saber-toothed predators like Dinictis and Hoplophoneus (both on display in our new Morian Hall of Paleontology), we see bite marks on the skull bones where there was lots of meat — the rear of the skull, the brain case and the tops of neck vertebrae. The extinct mammals ate like the highly efficient carnivores in today’s world. Saber-toothed cats did not waste much time and energy gnawing bony, meat-poor zones of chin and snout. Neither did the extinct dog-like Hyenodon.

Our Dimetrodon was a very, very primitive reptile. In fact, in most ways, D’don was even more primitive than a crocodile or komodo dragon. One big deficiency was the set of meat-slicing teeth. Dimetrodons didn’t have the enlarged self-sharpening chompers. The upper rear teeth could not slide past the lowers in a honing action. Therefore, so the theory goes, a Dimetrodon would have been sloppy and slow and inefficient when dismembering big carcasses.

If D’dons were really as sloppy as crocs and komodo dragons, then we’d find bite marks all over skulls and necks. But if D’dons were careful and efficient, they would have left tooth marks concentrated on the meaty zones of heads and necks.

When we analyzed bite marks on all the necks and heads from our digs, I was flabbergasted. (Talk to anyone in the lab — Dr. Bob hardly ever gets gabberflasted.) Our supposedly primitive Dimetrodon did not bite a la lizard. Or a la crocodile. Or a la gator.  Bite marks were targeted with consummate precision. Little energy had been wasted gnawing at non-meaty parts. Bony snouts and chins were not chewed upon. Instead, the tooth marks had been concentrated on all the most meaty zones of the head and cervical region. Bites on the braincase are exactly where big, thick muscles attached. Bites on the cheek are where the jaw muscles attached. Bites on the neck are where the thickest cervical flesh was located.

I have new respect for the Texas Red Beds Dimetrodon. Whenever we unearth another D’don victim, I doff my hat in honor of its masticatory prowess.  Our modern mammal efficiency began a hundred million years earlier than we had thought. And now, when we do lunch at Smokey Bros Barbecue and we chew succulent brisket and bring a doggy-bag back to Skippy, we thank our fin-back ancestors.

Extra! Extra! Our dinosaur bath makes front page news and Dr. Bakker’s back in town

Check, check it out:

The Morian Hall of Paleontology gets some front-page love

That’s right, the long-deceased residents of our Morian Hall of Paleontology got some front page attention Tuesday after a weekend cleaning courtesy of Associate Curator of Paleontology David Temple and artist-cum-dino-installer John Barber. You think cleaning your living room is hard? Try cleaning dinosaur bones. It takes delicacy, focus and a steady hand. Just listen to Houston Chronicle reporter Allan Turner’s account of the meticulous process:

In their arsenal are a compressor capable of blasting air at 60 pounds per square inch and its 6-foot wand, a tool designed for the purpose by Barber.

For the most delicate work, the men use makeup brushes, as well as brushes designed for the application of wallpaper paste and gold leaf.

Our hall has seen 350,000 people since June and accumulated plenty of dirt and residue from dander, dust mites and clothing fibers. In order to keep our specimens looking spotless, Temple undertakes several three to four after-hours cleaning sessions per year.

Want to learn more about the inhabitants of our Morian Hall of Paleontology — and how they came to perish? Our distinguished Curator of Paleontology, Dr. Bob Bakker, hosts a lecture on Tuesday, Oct. 30 called “Life After the Dinosaurs: Darwinian Saga of the Mammalia.

Bakker will explain how climate change helped mammals overtake dinosaurs approximately 65 million years ago. To purchase tickets, click here.