Adams's CV


Adam Nelson


Research Interests

I am interested in how the social environment affects the evolution of populations. Like many other organisms, house mice experience both high and low density populations. In fact, a mouse population can go from low density (a few mice per acre) to high density (hundreds of mice per acre) in just a couple of months. How does selection differ between these two environments?

House mice live in a remarkably complex social environment: they form dominance hierarchies, communally nest and nurse their young, and choose mates based on genetically and physiologically determined traits. Mice also communicate to each other with an elaborate system of scent-marking and pheromones.

Traits that are beneficial during social competition and sexual selection are often very costly to produce, so we predict that selection will tend to down-regulate or eliminate such traits in low-density populations. Conversely, selection should favor such traits in high-density populations, where there is greater opportunity for social and sexual selection. We are also interested in determining whether mice always have the genetic and phenotypic capacity to meet the demands of these two environments, or whether selection favors alternative genotypes and phenotypes as population density fluctuates.

We are using a selection experiment to address these questions. Specifically, the “Selected” lineage competes for mating success and social dominance in semi-natural populations of 30 individuals. On the other hand, the “Nonselected” lineage is bred under enforced monogamy and is therefore representative of a low-density population where there is no opportunity for social and sexual selection. Comparisons between Selected and Nonselected mice have shown that profound behavioral differences arose in as little as two generations. Using a candidate gene approach, our current research focuses on the genetic basis of these phenotypic differences. We are also collaborating with Emma Whitelaw of the Queensland Institute of Medical Research to investigate the role of epigenetics in this experiment.

My research is currently supported through the University of Utah Training Program in Genetics, funded by the National Institutes of Health. I am also supported by a doctoral dissertation improvement grant from the National Science Foundation.