AboutDavid Prus Expertise I can answer any general questions about dinosaurs and on prehistoric mammals in the Cenozoic. I also know a bit about the media's various depictions of dinosaurs and their inaccuracies. I don't know much about "microfauna"-small animals, or about Paleozoic besides some knowledge about Permian animals. Plants are right out, I'm afraid.
Experience I have been interested in dinosaurs for most of my life, own a large collection of scientific papers and books on the subject, and am a member of the Field Museum in Chicago.
Education/Credentials I am in college, but studied biology and geology both in high school and as a personal effort.
Question Thank you for answering all my questions:
1)Which dinosaur had the most powerful jaws for its size, and what structures made this jaws so powerful??
2)Can you tell me the length and weight of the following animals:
Kelenken
Dinofelis
Amphicyon
Epicyon
Saurophaganax
3)Which extinct cat had the most powerful forelimbs??
4)Can you describe me how the skull of Xenosmilus was built like??
5)If Smilodon fatalis was introduced in Yellowstone national park, what would happen??
Thank you.
Answer 1. Hard to tell, but probably our old friend Tyrannosaurus (although hadrosaurs and ceratopsians came very close). Its secret was the bones connecting the maxilla, or upper jaw with the fused nasal bones on top of it and the lacrimal bones to the rear of the skull. That way, the entire force of the bite could be distributed all around the head, and the heavy build of the head allowed this force to distribute without hurting the animal.
2. Kelenken was 9 feet tall at the head, and weighed between 300 and 400 lbs
Dinofelis was the size of a large jaguar, and so probably weighed 300 lbs and was five feet long
Amphicyon was more than six feet long and weighed more than 1200 lbs
Epicyon was five feet long and weighed 170 lbs
Saurophaganax was forty feet long and weighed 3 short tons
3. Hard to tell. It was either the bearlike Barbourofelis or the largest true sabertooth Smilodon
4. Xenosmilus' skull was more heavily built than Smilodon, with short, broad teeth, a shorter skull, and a thicker, more robust lower jaw. This cat was a real bruiser
5) It would probably do well hunting bison and elk. It would be an ambush predator and less successful that wolves, but would probably displace the puma like jaguars do in South America. It would have no humans to act as competition, but would have to eat smaller food. I can imagine an animal smaller and rarer than the extinct Smilodon, but it would survive.
