AC professor give final Lunch Lecture of Dino Days


Austin College Physics Chair David Baker gave a diverse group of dinosaur enthusiasts the final Lunch Lecture of the Sherman Museum’s Dino Days exhibit Friday.

Baker’s presentation, titled “Extreme Changes: What Killed the Dinosaurs,” gave the leading hypotheses for the extinction of the dinosaurs and led the audience through them to determine the one that was most likely. Baker’s audience was an eclectic group of children and adults who had many questions for the Austin College professor following the presentation.

“This particular audience was interesting,” Baker said. “Ages six to retired folks, and there were palentologists in the audience and people that were just interested. I tried to make a presentation where somebody could walk away with something regardless of your expertise.”

The lecture took the audience through the Cretaceous Period — 145 million to 65 million year ago — and into the Tertiary Period — 65 million to 55 million years ago. Baker explained that the K-T Boundary is the layer in the Earth’s surface associated with the demise of the dinosaurs. During the time that layer was exposed, 80 percent of all species on the planet died.

He then presented the first hypothesis for the extinction, volcanism. Baker explained that the prominence of heavy volcanic activity led to a global cooling of roughly four degrees, which would have severely hampered life on the planet. The other hypothesis was an asteroid impact at the Chicxulub crater near the Yucatán Peninsula. While the asteroid impact is the general consensus from researchers for the cause of the extinction of the dinosaurs, Baker said both hypotheses likely had some impact on it.

Doug Hoover, one of the local dinosaur enthusiasts to attend the lecture, said that he enjoyed the presentation and picked up some fine points he hadn’t learned from television documentaries.

“It was great,” Hoover said. “I watch so many documentaries they pretty much touch on everything.”

Sherman Museum volunteer Michael Cuthbertson, who will be starting the seventh grade at S&S in a few weeks, also enjoyed the lecture and said he found out things he didn’t know.

“It left me wanting more because I didn’t get the chance to get past the volcanism,” Museum Executive Director Dan Steelman said. “I had to go upstairs because there were a lot of kids up there. I really enjoyed the fact that he laid out the criteria — this is what happened, what would have occurred for this to happen? Then you start working it out like a puzzle. I think that was probably the best way to go about doing it.

Steelman said he was hoping to get Austin College involved in Dino Days and was thrilled to discover Baker had a presentation that tied in perfectly with the exhibit. The physics professor was impressed with the museum’s exhibit and said he was happy to be associated with it.

“In fact one of the neatest things, I think, are these fossils that you can touch — these ammonites,” Baker said. “Yes, the dinosaurs didn’t survive, but these things didn’t survive either. In fact, they’re more representative. Ninety percent of marine species were wiped out and this was one of them. You can go fossil hunting in Lake Texoma for these.”