The Secret Weapon that Allowed Dinosaurs to Take Over the Planet Becomes Official Ted Talk
Leslie Capo, Director of Informational Services
A TEDxLSU Talk given by Emma Schachner, PhD, assistant professor of cell biology and anatomy, has now been published as an official TED Talk, available here. In it, Dr. Schachner explains a possible reason why dinosaurs were not only able to survive, but to thrive during the Triassic period more than 200 million years ago. And it's not what you think.
“When people think about why dinosaurs were so amazing, they usually think about the biggest or the smallest dinosaur, or who was the fastest, or who had the most feathers, the most ridiculous armor, spikes or teeth,” Dr. Schachner notes. “But perhaps the answer had to do with their internal anatomy -- a secret weapon, so to speak. My colleagues and I, we think it was their lungs.”
During the Triassic period, oxygen levels have been estimated to have been as low as 15% compared to today's 21%, so lungs capable of better handling a low-oxygen environment would confer a significant advantage. But since all that is left of dinosaurs is fossilized skeletons, what kind of information could scientists have about their lungs?
Schachner, who is a paleontologist as well as a comparative anatomist, explains. “The method that we use is called ‘extant phylogenetic bracketing.' This is a fancy way of saying that we study the anatomy -- specifically in this case, the lungs and skeleton -- of the living descendants of dinosaurs on the evolutionary tree. So we would look at the anatomy of birds, who are the direct descendants of dinosaurs, and of crocodilians, who are their closest living relatives, and then we would look at the anatomy of lizards and turtles, who we can think of like their cousins. And then we apply these anatomical data to the fossil record, and then we can use that to reconstruct the lungs of dinosaurs. And in this specific instance, the skeleton of dinosaurs most closely resembles that of modern birds.”
Schachner goes on to detail her conclusions about the anatomy of the dinosaurs' lungs and why they would have been able to function better than those of early mammals who were competing for the same resources.
So what bearing can what happened 200 million years ago to an extinct species have on us?
“Understanding the impacts of atmospheric O2 and CO2 on the evolution, diversification, and extinction of animals is extremely important for humans as we face impending impacts of climate change on our future survival and success,” Schachner concludes.
TED is a nonprofit devoted to spreading ideas, usually in the form of short, powerful talks (18 minutes or less). TED began in 1984 as a conference where technology, entertainment and design converged, and today covers almost all topics — from science to business to global issues — in more than 100 languages. Meanwhile, independently run TEDx events help share ideas in communities around the world.