EAGER: Social Context and Functions of Testosterone Pulses in wild California mice

University Of North Carolina Greensboro, Greensboro NC

Investigators

Abstract

In nature, animals need to respond rapidly to changes in their environment. This is especially true for males of species in which both males and females help to raise young because males have to both defend territories and care for young. One mechanism that might explain this quick change is the rapid release of testosterone (T). When T is released, animals show a preference for the place in which they were located at the time of T release. We will test whether, in nature, the context (defending a territory at a home range boundary or being a caring parent at a nest) of the T release has an influence on behavior. We predict that when T release occurs near the territory boundary, the animal will interact with intruders, likely in conjunction with ultrasound vocalizations. On the other hand, we predict that when T release occurs near the nest, the animal will focus its attention on its mate and offspring. We will test our predictions by injecting T into monogamous California mouse males at their territory boundary and at their nest and look for behavioral responses using remote sensing methods that include automated radio-telemetry, acoustic recording, and thermal-imaging. Our results are expected to provide evidence that T is an important hormone for regulating relatively rapid tradeoffs among behaviors involving competition and those involving the mate and offspring. This project is an important collaboration between an R1 and small research campus in which all participants will be uniquely trained in innovative approaches that address cutting edge yet fundamental issues in animal behavior. All aspects of this project will reach the broader public through our community outreach program entitled Bats and Mice In Your Backyard and our widely accessed www-based streaming content and field blog. We will broaden participation in this project through recruitment efforts for the field assistant at a local California State University campus near our field site. We also have exercises in place to formally assess our broader impacts.