Most animals display innate behaviors - behaviors that are strongly influenced by genetics and are not strictly taught or learned. These innate behaviors can evolve if they contribute to differential reproductive success of individuals that display the behavior. The focus of this project is to examine how genetic changes lead to differences in innate burrowing behavior between two species of mice. Deer mice (Peromyscus maniculatus) build small burrows with only a single, short entrance tunnel, while their sister species, oldfield mice (P. polionotus), construct long burrows with both an entrance and an escape tunnel. The long entrance tunnel and addition of an escape tunnel are probably adaptations for avoiding predators in the sparsely vegetated habitat that oldfield mice occupy. By interbreeding these two species and examining the behavior of hybrid offspring with molecular and statistical tools, this research will answer two primary questions: how many and which genes contribute to the increased length and escape tunnels seen in oldfield mouse burrows? Preliminary results suggest that changes in only a few genes may explain most of the differences in burrow shape and size. Overall, this research aims to dissect the genetic basis of an ecologically-relevant behavior in natural populations of mice.
A detailed understanding of the genetics underlying burrowing in these two species will provide an empirical framework for studying the genetics and evolution adaptive behaviors in general. The broader impacts of this research include: (1) engaging undergraduate students in research, and (2) explaining both the methods of behavioral and genetic research and its importance to the public through museum exhibits.
