Did certain primates evolve good eyesight as a mechanism to deal with venomous snakes?

The keynote speaker at William and Mary’s 2007 Neuroscience Spring Symposium believes it’s probable. Lynne Isbell, an anthropology professor at University of California, Davis, will discuss “Eve’s Legacy: Snakes, Vision and the Origins of Primates” at the symposium, to be held from 3-5:30 p.m. on Thursday, March 29, at the University Center, Tidewater A. Isbell will join two presenters from William and Mary’s interdisciplinary neuroscience program.

Isbell believes that a survival-based need to spot snakes triggered evolution of visual-acuity systems in African primates. She said that very early anthropoid primates species, ancestors of modern apes, were small enough to be prey for snakes.

“Primates as a whole have evolved really good visual systems—compared to other mammals—because they had the necessary preadaptations for going in that direction in response to snakes,” she said. “But having said that, I think that primates also vary in their visual acuity because they have spent different amounts of time with venomous snakes.”

Isbell points out that Malagasy lemurs never had to live with venomous snakes and happen to have the simplest visual systems of all primates. On the other hand, monkeys and apes of snake-rich Africa and Asia have the best vision in the primate world. In between, she says, are New World monkeys, with visual systems that are more variable, “perhaps because they’ve had intermittent exposure to venomous snakes.”

Two presentations from William and Mary’s neuroscience faculty will precede the keynote. Pam Hunt, from the psychology department, will speak at 3:00 p.m. on “Modeling the behavioral phenotype of fetal alcohol spectrum disorders in the rat: Highlights from my students’ research.” John Griffin, from biology, will speak at 3:20 p.m. on “Hypothermia Happens.” Isbell’s keynote will be at 4 p.m.

“We’re covering all the bases—and then some—with this symposium,” said Griffin, director of the neuroscience program. “We have presenters from two of the five departments participating, plus adding an anthropology factor. This ought to be interesting to just about anyone.”

The program is jointly sponsored by the Neuroscience Program and the Department of Anthropology.