9724037 Stevens Behaviors affect life, death and reproductive characters of individuals and populations and it is important to understand their expression and evolution. Understanding the expression of a behavior requires understanding the genetic basis of the behavior, the physiological basis of the behavior, the relationship between the behavior and fitness as well as effect of natural selection on the behavior. This research will use an insect model system to understand the role of genetics, physiology and selection in the expression of a behavior - cannibalism behavior in the confused flour beetle Tribolium confusum. Because behaviors are likely to be determined by or highly correlated with other traits - including basic physiological processes such as metabolic rate or respiration rate - the genetic basis of and selection on respiration rate and surface behavior (i.e., the tendency of beetles to be on the flour surface rather than tunneling in the flour media) will also be examined. Using high and low cannibalism strains, experiments will determine if there is single optimum expression of a behavior in a given environment, by creating populations with differing allele frequencies of cannibalism genes and tracking the change in allele frequencies over time. Statistical analysis will be used to determine the relative importance of selection vs random processes in behavior evolution. The proposed research will also examine the controversial, virtually untested portion of Wright's shifting balance theory, namely the plausibility of a population moving from one adaptive behavior stratagy to another by migration among populations. The genetic analysis will be done using recent developments in molecular genetics including quantitative trait loci (QTL) analysis. A molecular genetic map of the genome of T. confusum will be constructed and used to identify regions of the genome associated with the behavioral and physiological traits. This rese arch is an important contribution to both behavior genetics and evolutionary biology because it tests common assumptions made about the adaptive significance of behaviors, as well as their genetic basis and evolution.