Comparative Genetics and Neurobiology of Nematode Feeding

University Of Texas Southwestern Medical Center, Dallas TX

Investigators

Abstract

The goal of this project is to understand how animal behavior changes during evolution. Closely related animals often have very different behavior that allows them to thrive in their environments. For instance, finches on the Galapogos islands have evolved to eat different kinds of seeds. These changes in behavior are puzzling, because, although behavior is the product of the nervous system, animals with different behavior often have nervous systems that look practically identical. This project studies feeding behavior in bacteria eating soil nematodes. Feeding in these very small worms is controlled by a tiny nervous system of just 20 neurons, which are the same in different species, even though they show obvious differences in feeding behavior. To learn how the feeding nervous system produces different behaviors, individual neurons are killed with a laser, and the resulting changes in behavior watched. Although the neurons look similar, they turn out to function differently. In the long term the project seeks to find genes that cause differences in behavior, concentrating on two species. Students will carry out this work as part of their training as research scientists. It will contribute to our understanding of the evolutionary relationships among soil nematodes, a huge and ecologically crucial group of animals, and of how they are adapted to their environments. More broadly, it seeks to learn why some things change in evolution, while others stay the same. Such understanding could be helpful in understanding when results from one sort of animal can be applied to another (mouse to human, for example).