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.

Homeosaurus a Living Fossil

Beasts of land and skies and the winner of the longevity award

The descendants  of Homeosaurus are alive and well today in New Zealand.

Homeosaurs looked like plump lizards from the outside. But their inner structure was distinctive. The skull was rigid so the snout couldn’t flex the way a lizard’s can. Plus, the teeth worked like self-sharpening scissors to slice through tough-skinned prey.

Tuatara, Nga Manu, Waikanae, New Zealand, 15 April 2006
Tuatara
Creative Commons License photo credit: PhillipC

Homeosaurs were the Ultimate Jurassic Survivors. They came from an old group that first evolved far back in the preceding Period, the Triassic. Today a homeosaur descendant, the Tuatara, still lives along the coast of New Zealand. No other family of Jurassic reptile has lasted so long with such little change.

How did they do it? What’s the secret behind homeosaur survival? We don’t know….yet. What do you think?

The Animals of Solnhofen – Geosaurus

Our Archaeopteryx show has bedazzling fossils – the only Archaeopteryx skeleton in the New World, complete with clear impressions of feathers. Plus frog-mouthed pterodactyls, fast-swimming Sea Crocs, and slinky land lizards. Today we learn about the Geosaurus.

Geosaurus – Shark-Tailed Sea Croc
Speediest of the ocean-going crocodilians

Some creatures of the Late Jurassic lagoon were up & coming evolutionary clans – the teleosts, for example, were just beginning their takeover of the marine ecosystem. Other groups were Darwinian ultra-conservatives, living fossils in the Jurassic, changing slowly or not at all. The Chimaeras are a fine example.

And then there were a few very special cases – Late Jurassic critters that had reached the apogee of Natural Selection, the highest development of their race. Best representative of this phenomenon:

The Super-Swimmer Croc, Geosaurus.

The earliest crocs of the Triassic were land animals, roughly fox-sized with long legs. In the Early Jurassic, crocs went into rivers and lagoons.  That’s not a surprise. All living crocodilians swim well in freshwater, and a few – the Florida Croc and the Australian Salt Water Croc – will go out beyond the surf and navigate between oceanic islands.

But…..no modern-day croc is super-specialized for life in the high seas. None have the double-lobed tail of the sort we see in big, fast sharks, like the White Shark. Open-water sharks have a characteristic double-lobe tail. The vertebral column takes a sharp bend upwards to support the upper lobe of the tail. The lower lobe is made of tough skin and connective tissue. You can see the double-lobed tail configuration in our Archaeopteryx show in the hybodont sharks, a family common in the Jurassic.

To compete with such speedy sharks, a croc would have to evolve a double lobed tail. No crocs did – except one extraordinarily graceful clan, the geosaurs.

Our exhibit is graced with one of the finest geosaur specimens ever dug. This awesome Solnhofen skeleton demonstrates how evolution had transformed a “normal” river & lagoon crocodile into a reptilian torpedo, an open water predator that matches a shark in efficiency.

Geosaur evolution made a sacrifice unusual among the crocodilians – it traded in armor for velocity. All early crocs from the Triassic  and earliest Jurassic had thick bone plates over the back and neck and all over the throat and belly. All modern day crocs too carry extensive armor plate. This armor is useful when crocs are attacked by land predators or by other crocs. Most of the sea-going crocs of the Jurassic and Cretaceous kept some armor. Case in point: armor was carried by the teleosaurs, big  sea-crocs who were the apex predators at Solnhofen and most other sites in the Mid and Late Jurassic.  There is excellent evidence that large Jurassic dinosaur meat-eaters did indeed attack teleosaurs.

The geosaurs went a different way. They went skinny-dipping.

Geosaur skin was totally devoid of bone armor plates. They were naked. This development made the geosaur body lighter and more flexible.

Fast-swimming demands a specialized flipper for steering. The “normal” croc has long front legs and very long hind legs. The hind legs have wide webbed feet and assist the tail in propulsion underwater. All modern crocodilians and most fossil species keep this arrangement.

The geosaur limb equipment evolved in a unique way. Those long, strong hind legs were retained. But the fore-limbs were transformed into short flippers that worked like the diving planes of a submarine. No other croc clan did this with their front limb.

Impressive….but the outstanding geosaur specialization was the tail. “Normal crocs” have a deep, strong tail that bends down just a little bit at the end. The geosaurs went far beyond “normal” – they evolved a tail almost identical in profile to that of a modern tiger shark or a Jurassic hybodont. The geosaur tail possessed  two lobes, one bigger than the other in shark-fashion. 

Take a good look at our geosaur…..notice something strange?

The tail is upside down!  The vertebral column bends down, not up the way it does in sharks. Mummified geosaurs show that the upper lobe was made from tough skin and connective tissue, just like the lower lobe of sharks. The hydrodynamics of the upside-down tail worked just as well as the right-side-up shark tail.

Here’s a wonderful example of how evolution works: Natural Selection is opportunistic. It operates on what is already there. “Normal crocs” already had a slight down bend of the vertebral column.  For “normal crocs” to evolve a right-side-up version of a shark tail was almost impossible. But evolution took the simpler path by emphasizing the downward bend and then adding the upper lobe.

No croc of any age matched the swimming efficiency of geosaurs (although the Cretaceous Hyposaurus, from my home state of New Jersey came close). Most other croc groups are distant seconds. Therefore, the Late Jurassic was the high point of croc-natatory prowess (look it up;  “natatory”, a good adjective).

Why? Why didn’t some later croc group evolve upside-down shark tails as specialized as those of geosaurs?  We don’t know. My guess is that sharks evolved so fast in the Cretaceous that crocs were pushed out of the open-water/fast-swimming niches.

One more thought – geosaurs probably had to crawl onto sandy beaches to build nests and lay eggs. Their tiny flipper-like fore limbs would have been a big disadvantage – mom geosaurs must have been far more vulnerable to land predators than “normal crocs.”

Jurassic Puckering – Kissing Fish and Salt Water Evolution

Our Archaeopteryx show has bedazzling fossils – the only Archaeopteryx skeleton in the New World, complete with clear impressions of feathers. Plus frog-mouthed pterodactyls, fast-swimming Sea Crocs, and slinky land lizards.

But wait…….there’s more!

The exhibit has spectacular Jurassic fish!

By “spectacular” I don’t mean gigantic. Most of the Jurassic finny species were small to mid-sized, salmon to tuna in bulk. The extraordinary thing about our Jurassic fish is that the fossils capture the single most dramatic moment in all of fishy evolution….

….The Teleost Takeover!!
Teleosts are the unrivaled Rulers of Fish-Dom. Teleosts make up three-quarters of today’s fish species. When you eat fish, chances are you’re eating teleosts: tuna are teleosts, and so are mahi-mahi, swordfish, bluefish, salmon, red snappers, trout, bass, eels, herring and anchovies…

Gefilte Fish?  Yep. Teleost. So are white fish, smoked or non-smoked. Sail fish, tarpon, guppies…..

Teleosts belong to the “Bony Fish Clan,” one of the two huge branches on the fish family tree. The other big branch is for sharks, rays and skates

Pucker Faces
What makes teleosts so great? Pucker skulls. Go to an aquarium or a really big fish store. Watch the feeding. Teleosts protrude their faces, pushing out the jaw bones so the mouth cavity expands. Water rushes in, carrying food. Large mouth bass expand their mouths so wide they can suck in an entire duck.

Teleosts can use their pucker faces to reach out and nibble. Parrot fish do that when they gnaw away coral polyps. Catfish use their suction-mouths to vacuum worms from a muddy bottom. Remoras use their pucker-sucker mouths to get a free ride from a big shark.

Ok – all fish anatomists (people who dissect fish, not guppies who get PhD’s) agree: the pucker-swing-out, expanded face & jaws is the key innovation that opens the door to thousands of potential ecological niches.

Pucker Free Times
It wasn’t always so. The first bony fish comes in at about 400 million years ago. For the next 200 million years, there was no puckering. Jaw bones were firmly attached to the rest of the skull. Today, we have one Texas fish that still is no-pucker – the garfish. It grabs prey the way a gator does, with a simple snap.

First Tentative Pucker
In Triassic times, about 220 million years ago, some bony fish evolved a semi-moveable set of jaw bones that let the mouth expand sideways. Bowfins today are at this stage of evolution. Our Jurassic fish show has some nifty bowfin fossils.

Teleost Shock Troops
Bowfins didn’t go far enough. In the Late Triassic and Jurassic the first teleosts evolved. Face and jaw bones became mobile. Sucker-pucker faces started to diversify. That’s just the stage we catch in our Archaeopteryx display. The Late Jurassic lagoon beds from Solnhofen, Germany, abound with this first wave of teleosts. Don’t take my word for it. Come close to the glass cases with Thrissops, Pholidophorus and other early teleosts. Check out the jaws.

Teleosts would continue to expand into the next Period, the Cretaceous, and the through the following Age of Mammals.

so…..come to the Archaeopteryx show for the feathers…stay for the fish-faces.