American Society of Naturalists

A membership society whose goal is to advance and to diffuse knowledge of organic evolution and other broad biological principles so as to enhance the conceptual unification of the biological sciences.

“Re-examining the causes and meaning of the risk allocation hypothesis”

Posted on

Barney Luttbeg

Prey have to balance avoiding predators and finding food. Periods of lower predation risk can provide prey with the opportunity to forage intensely while risk is relatively low. Lima and Bednekoff in 1999 presented their risk allocation model and showed that as the frequency of high-risk periods increases prey are expected to increase their foraging efforts during both low- and high-risk periods. In a new article appearing in The American Naturalist, Barney Luttbeg of Oklahoma State University presents a model that explores how the predicted behavior of prey is affected by receiving imperfect information about the current state of their environment. Imperfect information has two main effects. It causes mistakes in prey behavior because individuals incorrectly assess the current state of their environment, and this weakens the risk allocation prediction. Long-term evolutionary exposure to imperfect information also changes how much individuals should rely on information they receive. The researcher finds that prey that have evolved in the presence of imperfect information can show a decrease in foraging efforts as the frequency of high-risk periods increases, which is a reversal of the risk allocation prediction. As environments continue to be quickly altered by human activities, a critical question is how individuals will behave and perform in altered environments. Luttbeg’s work highlights that the answer to this question will depend on how past environments have shaped the expectations and cognitive rules of individuals. Read the Article