What’s up with dinosaurs?

What would the summer be without a dinosaur film? This year it’s Jurassic Park III–testimony to the continuing fascination these ancient creatures hold for modern humans.

But there’s more news in the world of dinosaurs than the latest special effects. In fact, in the past little while there have been several dynamite dino-developments.

The most recent is the discovery of the second-largest dinosaur ever discovered, the 94-million-year-old Paralititan stromeri, around the Bahariya Oasis, about 200 miles southwest of Cairo in the heart of the Western Desert of Egypt.

German Ernst Stromer first exacavated the site in the early 1900s and took a number of fossils of smaller dinosaurs to Munich, but in 1944, Allied bombing essentially destroyed his collection. Then, two years ago, University of Pennsylvania Ph.D. candidate Joshua Smith went back to the site, with funding from film company MPH Entertainment (watch for “The Lost Dinosaurs of Egypt” on A&E.)

Paralititan stromeri is huge: its fossilized humerus, or upper arm bone, is 1.7 metres long, which indicates the dinosaur measured 24 to 30 metres in length and weighed 55 to 65 tonnes. But more importantly, it’s not only a previously unknown species of dinosaur, but the first member of a whole new genus.

As well, the bones were found with the fossilized remains of fish, turtles, crocodiles and fern trees, and geological evidence the site was near the seashore. It appears Paralititan stromeri lived in a mangrove wetland similar to the Florida Everglades. It’s the first time dinosaur fossils have been definitely placed in such an environment.

Some scientists have felt that present-day South America and Madagascar were linked during the Cretaceous Period, while Africa was not, mainly because giant plant-eating dinosaurs had been found in South America and Madagascar, but not Africa–until now.

The most recent giant plant-eater found in South America was even bigger than Paralititan stromeri. Argentinosaurus, found, as you might have guessed, in Argentina, was a full 10 metres longer. Its shoulder blade alone was bigger than a Volkswagen Beetle. (To put it another way, both Paralititan stromeri and Argentinosaurus could easily have straddled a modern-day elephant.)

How could a creature that large survive? Study of these giant dinosaurs has revealed backbones that interlocked in a special way to create a bridge of bone strong enough to support the creature’s weight. As well, the bones were hollow, a strategy that maximizes size and strength while minimizing weight.

The same region of South America that gave us Argentinosaurus has also yielded the fossils of the carnivorous Gigantosaurus, bigger even than the more famous Tyrannosaurus rex. And last year, researchers–including Philip Currie of the Royal Tyrrell Museum in Drumheller–announced they had found and even bigger carnivore–not just one, but a whole herd, some adults, some babies. That could mean large carnivorous dinosaurs–including T. Rex–hunted in packs, rather than being solitary as has long been thought. Such a pack would have been fully capable of killing and bringing down even a dinosaur as large as Argentinosaurus.

Meanwhile, in China, other discoveries are adding evidence to the claim that dinosaurs, far from dying out when an asteroid hit the Earth 65 million years ago, are still with us–as birds.

There are many similarities between the skeletons of birds and dinosaurs such as the tyrannosaurs and the “raptors” of Jurassic Park fame. And recent discoveries in China seem to indicate that at least some dinosaurs already had feathers long before birds appeared. The most recent evidence is a fossil unearthed in the Chinese province of Liaoning. As yet unnamed, the 65-centimetre carnivore had limbs that reminded researchers of a duck’s, except its arms ended in three-fingered, clawed hands. The well-preserved fossil includes the imprint of what appear to be down feathers covering the body and long, thin feathers covering the arms.

This bolsters the idea that feathers first appeared as insulation, and only later were adapted for flying. Insulation, in turn, is evidence that these dinosaurs were warm-blooded, not cold-blooded.

The majority of scientists seem ready to accept that birds are direct descendants of dinosaurs, but there are still some critics who deny that the feathery imprints are of feathers at all. They suggest they could have been left by decaying skin or feathery mineral crystals.

The debate continues. In the field of paleontology there are always more questions–but also, as this week’s news from Egypt proves, always more discoveries, too.

Permanent link to this article: https://edwardwillett.com/2001/06/whats-up-with-dinosaurs/

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