Behavioural Ecology

Abstract

Behavioural ecology is a branch of biology that seeks to understand how an animal's response to a particular situation or stimulus is influenced by its ecology and evolutionary history. Areas of research in behavioural ecology are varied, and include mate choice, brood parasitism, co-operative breeding, foraging behaviour, dispersal, territoriality and the manipulation of offspring sex ratios. As with other fields of ecological research, the study of behavioural ecology was traditionally based on either laboratory or fieldwork. Laboratory work has made many important contributions because it allows us to manipulate organisms under controlled conditions and observe them at close quarters. At the same time, laboratory-based research is limited because many species cannot be kept in captivity; of those that can, observations must often be interpreted in context because captive conditions can never exactly mimic those in the wild. Observations and experiments involving wild populations have also been a valuable source of information, although again there are limitations; for example, it may not be possible to identify individuals or to follow and observe them for prolonged periods. In addition, even if researchers are able to faithfully observe individuals for a prolonged period, they still may be missing part of the story: if a female is copulating with multiple males, for example, observations cannot tell us how many, or which, of these copulations led to fertilization.In recent years, molecular data have often been used to supplement the more traditional approaches, particularly when studying individuals in the wild. From small amounts of blood, hair, feathers or other biological samples (recall noninvasive sampling from Chapter 1) we can generate genotypes that can tell us the genetic relationships among individuals, or identify from which individual a particular sample originated. In this chapter we shall first concentrate on how molecular data have greatly enhanced our understanding of mating systems, kin selection and adaptive sex ratios. We shall then look at some of the ways in which population genetic data can help us understand sex-biased dispersal, a crucial behaviour that has profound impacts on how genetic diversity is distributed around Molecular Ecology, Second Edition