Optimal behavior: can foragers balance two conflicting demands?

According to much current theory, organisms should be able to balance the conflicting demands of the need to feed efficiently and the need to avoid preadtors while feeding. In an experimental conflict situation, it was possible to evaluate the relative fitnesses associated with the available choices and to compare the observed behaviors with predictions derived from fitness considerations. A backswimmer, Notonecta hoffmanni, was capable of balancing these two conflicting factors adaptively.