The first challenge for biologists is characterizing morality in terms amenable to science. Abstract concepts of 'right' and 'wrong', or virtuous motives and good intentions, must be expressed in terms of what can be observed or measured. First, then, biologists address morality concretely as a form of behavior. As such, it fits in a context of other behaviors: foraging, mating and nesting, securing territory, play, grooming and other social interactions.