Friday, July 22, 2016

South Dakota School of Mines Museum of Geology

Recently completed a field camp course hosted by the South Dakota School of Mines and Technology. There were many magnificent sights to see out there in Wyoming and South Dakota, but having to regularly scramble up and down rock outcrops did not encourage the use of my good camera. Additionally, photography tends to take a backseat when you are being graded for your field work, the net result being that I only have a handful of relatively low-quality photos from field camp proper. However, once the course was done, I got the chance to visit SDSMT's own Museum of Geology, at which I was free to be more shutter-happy. Despite the small size of the display area, the museum's collection was quite impressive. It was also nice to see an exhibit on conservation paleontology.

A row of skulls showcases the evolution of that iconic North American megabeast, the American bison.

Most of the specimens displayed here were discovered at local fossil sites (some of which we worked at during field camp). Here is a skull of the nimravid Hoplophoneus with a painful-looking bite mark.

Smilodon compared to living cats, including (clockwise from top left) a house cat, a bobcat, a clouded leopard, and a mountain lion.

More Hoplophoneus skulls.

This is a specimen that had to travel some ways to get here, a juvenile Mauisaurus.

The centerpiece of the museum was a mount of another plesiosaur, Styxosaurus. It was so big that it was essentially impossible to fit it all in one shot.

The skull of Archaeotherium, a hell pig (but not really a pig).

The foot of the hornless rhino Subhyracodon.

The skull of Subhyracodon.

Protoceras, a member of an extinct radiation of North American artiodactyls with bizarre headgear.

How many universities have their own Tyrannosaurus rex?

A Mosasaurus mount. Spot the palatal teeth!

The skull of the amphicyonid Daphoenus.

A glass case showcased brontothere sculptures by Charles Knight.

A partial skeleton of an Oligocene snake.

A full-body mount of Archaeotherium.

Leptomeryx, a small ruminant.

An oreodont mounted with unborn young in its womb.

A gomphothere skull.

The brontothere Brontops.

Ah, a maniraptor! Procrax, a fossil cracid fowl.

A mount of Edmontosaurus (or is it Anatosaurus?).

Glad that they acknowledged that the mount is in an outdated posture.

Should be "femora"!

The skull of Triceratops.

Mosasaur stomach contents.

Considering the ubiquity of cannibalism among modern carnivores, "mosasaurs probably were NOT cannibalistic" is a bold claim to make.

A partial skull of the mosasaur Hainosaurus.

Mesosaurus, not a mosasaur.

There was a screen playing Valley of the T-Rex [sic]. Ehh.

Friday, June 3, 2016

Dinosaurs Among Us at the AMNH

Upon learning the American Museum of Natural History was opening a temporary exhibition on bird origins, my first instinct was that I had to go. Fortunately, Maryland is in close enough proximity to New York that I was able to make that a reality.

A fair amount of space is devoted to the evolution of avian reproduction, including characteristics shared with their closest living relatives (crocodylians) as well as our understanding of reproduction in Mesozoic theropods. Here is the oviraptorosaur embryo "Baby Louie".

A model of a giant oviraptorosaur nest with a restoration of the probable parent, Gigantoraptor. The dinosaur restorations at this exhibit are (thankfully and expectedly) above average, but a few pennaraptors still suffer from primary-eating feather mites. It's time to stop, please.

The famous "Big Mama", a Citipati preserved brooding on its nest.

An oviraptorosaur with unlaid eggs still in its body cavity! The paired eggs indicate that non-avialan theropods still had two functional ovaries, unlike the single one in modern birds.

A gallery of bird eggs, including both extant and extinct species.

A gallery of pennaraptor skulls and endocasts, showing the evolution of the avian brain. I was glad to see Dr. Eugenia Gold as one of the talking heads on a nearby video screen, considering that her recent research has focused on avian endocranial anatomy. Notice the "bird-o-meter" next to the labels of the fossil dinosaurs, indicating how closely related each one is to modern birds.

A wonderfully-preserved pair of Khaan that were found in close proximity to one another. The wording on the signage was sensibly cautious about interpreting them as a male and female. (Hint: dimorphism cannot be demonstrated with a sample size of two...)

Another excellent fossil, this time of Velociraptor. This may be the "sleeping" Velociraptor specimen I've heard rumors about.

A gallery of furculae. The largest one belongs to Tyrannosaurus.

I was impressed by how up to date some of the displayed information was. Here, recent discoveries of one-way breathing in crocodylians, monitor lizards, and iguanas are used to explain the evolution of the avian respiratory system.

There were a number of life-sized models of representative feathered dinosaurs, including this Beipiaosaurus.

In fact, a virtual parade of life-sized models and partial mounts made up the centerpiece of the exhibit. Here is a fairly nice Velociraptor. (Additionally, I overheard more than a few expressions of surprise from other visitors who were learning that non-avialan dinosaurs had feathers, both a reminder that this fact is not common knowledge outside of the paleontology community as well as real-time demonstration of the value of exhibitions like this one.)

As the largest dinosaurs with direct preservation of feathers, Yutyrannus stole the show.

A fossil cast of Yutyrannus in all its glory.

Some interesting speculation on the presence of feathers in large dinosaurs.

Fluffy ornithischian Tianyulong. Shame about the pronated hands.

An Archaeopteryx that looks like a real animal and not a half-lizard freak. Good job.

A cast of the Berlin Archaeopteryx and the original holotype feather.

An oviraptorid with young. The oviraptorids (there are others not pictured here) were the best models on display, in my opinion. I should have taken more pictures of them.

On the origin of flight, here is an Anchiornis performing wing-assisted incline running.

A cast of "Dave" the (possible) Sinornithosaurus.

A cast of Caudipteryx.

A cast of Tianyulong.

Feathers did not evolve in an aerodynamic context.

This... is one of the few parts of the exhibition that I had issue with. It's fair enough to point out that the developmental homologs of feathers originated long before the evolution of birds, but it does not thus follow that feathers themselves arose at the base of Archosauria (as implied by the accompanying restoration). On top of that, picking Effigia, a pseudosuchian that happens to have several other convergently bird-like characteristics, to clothe in feathers may come across as more than a little misleading. It would be cool if crocodylians were ancestrally feathered. However, we do not have the data to claim they were as of yet.

A lithornithid with fossilized feathers (and Effigia skull at top left).

A cast of Anchiornis. Are we seeing some of the original color pattern on those wings?

Juravenator shows that feathers and scales are not mutually exclusive.

Microraptor represents early experimentation with aerial locomotion in paravians.

Confuciusornis (left) and Xiaotingia (right) may have also had varying degrees of flying ability.

Look, it's Yi!

Jeholornis shows that feathers can function in display, too.

I liked the fact that some space is dedicated to Cenozoic birds as well. Here is another lithornithid.

That's stem-roller Paracoracias on the left and... another lithornithid on the right? My memory fails me on this one.

The skull of Gastornis.

A comparison of flying vertebrates.

An entire wall showing the stepwise acquisition of "avian" traits and the nebulousness of the term "bird". Unfortunately, some workers were repairing the interactive "test how well each dinosaur can fly" game, so I could neither get a better picture of the wall nor observe how the game worked.

The final display case contained a currently unnamed troodont, reportedly soon to be described.

A small gift shop directly followed the exhibition. One of the creatures on this shirt is not a dinosaur. (Surely, it would have made a better tie-in to the exhibit if they had included at least one bird on the shirt?)

Half of these titles belongs. The other half... doesn't.

Despite some minor quibbles about life restorations and feathered pseudosuchians, I found "Dinosaurs Among Us" to be excellent. It presents our understanding of avian origins in an incredibly current and multifaceted manner, and there is little I would add or change if I were in charge of making such decisions. Check it out if you have the chance! (It is open until January 2nd of next year.) It was well worth the long train ride to and from New York, and that's a trip I wouldn't make again in a hurry.

... What do you mean, there is also a pseudosuchian exhibit now?