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Albany, NY – This week on The Academic Minute, we are honoring the winners of our First Annual Academic Minute Senior Superlatives.
Today's Academic Minute is from Dr. Tim Rowe of the University of Texas at Austin. The University of Texas public relations team, led by Robert Meckel, was awarded the Best Press award for providing timely responses to requests and presenting listeners with wonderful ideas from their institution.
Timothy Rowe is a professor in the Department of Geological Sciences in the Jackson School of Geosciences at the University of Texas at Austin. Dr. Rowe also directs the Vertebrate Paleontology Laboratory of the Texas Memorial Museum. His research focuses on the evolutionary development of the extinct Mesozoic vertebrates of Texas and the American Southwest.
Dr. Tim Rowe - Evolution of the Mammalian Brain
Among living animals, mammals have the largest brains relative to their body size. This holds true for big mammals like whales for medium sized ones like you and me, for dogs and cats and small ones like mice. Even the earliest mammals had big brains.
For years, I and a lot of other scientists have wondered why. We know they weren't doing calculus. So what were they doing with those bigger brains? And how did big brain size evolve and what were the driving mechanisms?
We've had fossil skulls of early mammals for many years, but they're rare and we couldn't tell much about their brains because the fossils were too rare and valuable to slice open. Then along came CT scanners. They were used in hospitals to make images inside patients' bodies. We founded a lab here at the University of Texas [at Austin] to use high resolution versions of these scanners to peek inside fossils without destroying them.
My colleagues and I scanned more than two dozen early fossil mammals and more than 200 living mammal species over the last 20 years or so and we compared them to understand why mammals had such big brains. We were surprised to find that as proto-mammals evolved into mammals, the first parts of the brain to expand were those related to the sense of smell. Compared to their more primitive ancestors, these first mammals were super smellers.
It makes sense that this stronger sense of smell would catch on in terms of evolution. It probably gave the first mammals the ability to sniff out bugs at night while allowing them to avoid being seen and eaten by dinosaurs. And once mammals had that head start - they were off and running. Even though we don't always show it, we all have bigger brains today thanks to those early super smellers.