Ankylosaurs aren’t very aerodynamic*

But they can still fly!

Ankylosaur Flying! [1.21.11]
Quite a view! See the entire set from the move on Flickr.

If you’ve never seen a dinosaur fly, then you weren’t in the vicinity of the museum around 11 am last Friday – at which time it was almost impossible to miss our airborne ankylosaur.

Pretty cool! The ankylosaur – an original created for the 1964 World’s Fair – has been a much loved part of our paleontology hall for decades. As part of the ongoing construction associated with our current expansion, the ankylosaur – along with several other displays from the hall – was de-installed and will be stored until it re-emerges in our new paleo hall in 2012!

Carolyn recorded this video – it’s amazing how fast this big guy hopscotched over our entire new wing!

More on the Ankylosaur!

HMNS Flickr Set“Warwick Towers Survive Dinosaur Attack” on Swamplot | Flickr set from allison362

*Excellent point, via twitter from @laelaps

Archimedes, Atoms and Archaeopteryx

Peter L. Larson, paleontologist and geologist, is a paleontologist and the president of Black Hills Institute of Geological Research in Hill City, South Dakota. Larson is on the research team investigating Archaeopteryx and other fossils at the SLAC National Accelerator Laboratory. Today he blogs about the fossil Archaeopteryx and how high powered X-rays helps us learn new things about this unique fossil.

  
Paleontologist. Pete Larson (left) at the SLAC National Accelerator Laboratory.

The discovery, sale and subsequent scientific examination of the sole surviving thousand year old palimpsest recording the work of Archimedes (who died in 212 B.C.) has made it possible to study fossils using high energy x-rays to map the distribution of elements across the surface of the rocks containing their remains. A group of scientists gathered at the Stanford Synchrotron Laboratory in Menlo Park California to study one of the iconic “missing links” of evolutionary biology, Archaeopteryx. This investigation was able to show that not only was there original material from the living Archaeopteryx preserved in the dino-bird skeleton, but that the “feather impressions” were not impressions of feathers, but the feathers themselves, preserved in the limestone matrix for more than 145 million years. This research has opened a door to a new dimension for the study of fossils. It gives us a new way to study soft tissue, the chemistry of preservation, and details that everyone thought were lost in time.

For details about the X-ray Fluorescence imaging of the Thermopolis specimen of Archaeopteryx, see the May 10, 2010 issue of the Proceedings of the National Academy of Sciences.

Take a tour of our current Archaeopteryx: Icon of Evolution exhibit with Pete in the video below, and don’t miss your opportunity to ask him questions during our upcoming online webinar session. Join us on June 17 at 10 a.m. as Larson answers questions about Archaeopteryx, the exhibition and his own research. Register here, or see instructions below.

Archaeopteryx: Tour the Exhibit with Pete Larson from HMNS on Vimeo.

To register for our online webinar with Pete Larson
1)      Click here.
2)      Click “Register.”
3)      On the registration form, enter your information and then click “Submit.”


How To Make a Perfect Fish – Two Views

Ed Note: Many fossils from the periods discussed and the Solnhofen locality are currently on display in Archaeopteryx: Icon of Evolution. Join a live online discussion about the latest research into the title fossil with paleontologist Pete Larson on June 17.

Intelligent Design – For Jurassic Fish

Louis Agassiz

Right now,  in the 21st Century, the “Intelligent Design” is the latest development in arguments about Creation versus Evolution. Bur it’s not a new idea. The Father of Fossil Fish Science, Louis Agassiz, used Intelligent Design to explain Solnhofen sharks and bony fish in the 1840’s and 1850’s.

Here’s how Agassiz laid out the argument:

Expert Engineering in Fins and Jaws
Fish today have bodies that fit their environment. Bottom-living sharks and rays have flat bodies. Fins and teeth are “designed” to crush clams and crustaceans these predators find hiding in the sea bottom. In the open sea water, fast-swimming mackerel have thin scales, plump, streamlined bodies, and tall, narrow tail fins that seem ‘designed’ to catch small fish in fast attacks.

Jurassic Fish Were Built For their World
Each and every slice of geological time had fish shaped just right to fit their ancient habitats. The Solnhofen Gyrodus had the deep body ideal for hovering in quiet water near a reef. It carried incredibly strong teeth, dental tools that let the fish bite off chunks of coral and snatch clams embedded in the reef.

In Every Period, Fish Habitats Were Balanced
Each extinct habitat was balanced by precisely the right sort of predators and prey. Gyrodus pruned the reef, eating away excess algae, crabs and coral growth. That way the reef stayed healthy and no species became over-abundant. The aggressive reef predator Aspidorhynchus hunted the Gyrodus and kept its numbers down to just the right levels – not too rare, not too common. The big, fast teleost predators, like Thrissops, did their job in keeping Aspidorhynchus numbers in check.”

According to Jurassic Intelligent Design, the entire Solnhofen reef ecosystem was crafted by an unseen Creative mind that planned every detail.

Serial Creation, Agassiz’s view of Creation was not static. The entire World Ecosystem was revolutionized by change every million years or so. At the end of the Jurassic, many fish species went extinct. New species appeared. More extinctions and more waves of new species appeared at the end of the Cretaceous. More and more extinction-replacements occurred all through the next  Period, the Tertiary.

These revolutions were necessary because the World Climate changed fundamentally. Jurassic seas were tropical and Jurassic lands were as steamy as hot-houses. But the climate got cooler in later Periods. The fish that were perfectly designed for the Jurassic were not optimized for the Tertiary Period. Each new wave of extinction and replacement was required to maintain the exquisite balance in reef and coral-biter, coral-biters and Apex Predators.

The Theory of Natural Selection

Charles Darwin

Darwin and the Perfect Fish
Charles Darwin too was worried about perfectly designed fish. He recognized the extraordinary adaptations in predators that let them catch prey and the delicate balance among species in most habitats. But Darwin argued that natural processes could make ecosystems perfect, or nearly so. His theory had only a few simple steps:

All jaws and fins and bodies vary in all species
When a naturalist studied hundreds of specimens of Gyrodus or a living species, jaws and teeth and fins varied within the the species. Studies of domestic animals – Darwin liked pigeons – proved that much of the variation was genetic. Breed a tall pigeon female with a tall male and the chicks were, on average, tall. Breed a bigger than average goldfish with another big goldfish, and their young will be bigger than average.

Variations Pop Up All the Time
In 1859, when he wrote “The Origin of Species”, Darwin didn’t know where variations came from. The understanding of genes wouldn’t come until after 1900. But Darwin did know that new genetic variations arose in every population.

Nature is Cruel and Most Individuals Die Young
A big reef fish might spawn a hundred youngsters each summer. Few would live beyond six months. Only 1% or less would survive to breed. That’s the basic calculus of ecosystems.

Nature “Selects” the Genetically Fortunate
If a fish or wild pigeon hatches out with just the right genes, it gets an advantage. It can live longer, grow faster, and reproduce earlier than its relatives. Generation after generation, the lucky genes accumulate. In a thousand generations, a fish or bird species can be transformed.

Natural Selection Works All the Time to Keep Systems Nearly Perfect
Nature keeps selecting the lucky genes and keeps most of the species ideally “designed” most of the time.  That’s how Jurassic predators were kept fine-tuned to their prey. When climate changed abruptly, old species died out and new ones evolved.

Whole Hole Catalogue – How to be a Dino-Skull Sleuth

Last month we had a great question about what was inside a dinosaurs head. Today, we look at a dinosaur skull and answer “What are all those openings in the head for?”  Dino skulls do seem totally, wholly hole-y.

Check out our exploded Archosaurus head. The appearance in life is at the top – we don’t really know the color but this fellow had to hide in the bushes, so we painted him green. Archosaurs is INCREDIBLY important in dino evolution. He’s way ancient – from the latest Permian Period of Russia, about 248 million years ago.

The holes in the Archosaurus head are the clues to how it and its close kin were about to evolve into genuine dinosaurs. There weren’t any true dinosaurs in the Late Permian – that would come later, in the Late Triassic, about 220 million years ago. But the basic proto-dino head architecture had been fixed in Archosaurus.

Some holes are easy – the nostril is at the front. The eardrum was in a little notch at the back. The eyeball was in the big oval hole, second hole from the rear. Now for the good part…..

….there are two big holes for jaw muscles behind the eye, one low on the side, the other high up on the top. These jaw-muscle holes are temporal fenestrae – they mark a huge clan of critters that include lizards, snakes, crocs and dinosaurs. We mammals have only one hole on each side, low on the skull.

But wait, there’s more: between eye and nostril  in Archosaurus is a big aperture that you WON”T find in a mammal,  a lizard or a snake. It was packed with a special air-chamber connected to the throat and lungs. When Archosaurus breathed, air went around through these chambers, keeping the head cool.

Many Early Triassic creatures, descendants of Archosaurus, carried these holes, and so did early crocodilians. We call the snout-hole group “Ruling Reptiles” which in Latin is “Archosauria.” Archosaurs took over the land ecosystem during the Triassic, monopolizing the roles of large predator and large herbivore. There was something in that head design that gave Archosaurs a competitive edge.

Then came dinosaurs. All early dinos had the same blueprint – two muscle holes behind the head, one big air-chamber twixt nose and eye. Don’t take my word for it. Go to our galleries and find the holes in our T. rex. You’ll find the same layout in stegosaurs and raptors, duck-bills and ostrich dinos.

That’s the end of the first hole lesson. Do your homework. Find photos of dino skulls and label the openings.