Mammal Societies

Abstract

The core of Darwin’s theory of natural selection is the realisation (based on Malthus’s demographic projec? tions) that the rate of population increase will inevitably lead to competition between individuals for resources and reproductive opportunities, and that competition will favour individuals that are well adapted to the environments they live in, with the result that their heritable characteristics will increase in future genera? tions. Empirical research on population ecology since Malthus has provided extensive evidence to support Darwin’s argument, while research in evolutionary biol? ogy and population genetics has confirmed that favour- able mutations are likely to spread. Natural selection adapts animals to the ecological niches that they occupy. Early explorations of animal adaptation mostly examined relationships between ana? tomical traits and the challenges imposed on different species by their physical environments. More recently, research has documented the impact of the social envi? ronment on the selection pressures operating on both sexes and on the evolution of behavioural, physiological and anatomical adaptations. In addition, an increasing range of studies have explored the consequences of contrasts in social organisation and the adaptations they generate for ecological processes within and between species, as well as for other areas of biology, including population genetics, epidemiology and conser? vation