his book on Animal Contests represents a landmark in evolutionary biology that is greater than its immediate title suggests. The adaptive interpretation of fighting behaviour in animals has been a catalyst in the study of evolutionary adaptation: first, it was influential in changing concepts about the mechanism of selection (from implicit group selection to individual selection), and second, it was the focus for shaping our understanding of frequency-dependent optimisation in biology through the evolutionarily stable strategy (ESS) approach. I regard it a great privilege and honour to have been invited by the Editors to write a Foreword, and I would like to use this opportunity to recount some of the history of these roles of contest theory in evolutionary biology, including my personal recollections of the events during that very exciting decade, the 1970s.

Before 1970

The way we now think of animal fighting behaviour owes most to the development of the first theoretical models of animal contests, developed in the 1970s. Before this time, with a few notable exceptions (e.g. Williams 1966, Lack 1968),most researchers in the disciplines of ethology and ecology routinely (and usually implicitly) applied group or species selection interpretations to what they saw. This ethos did not generally apply to evolutionary biologists or population geneticists, whose analyses were usually founded on principles derived from Darwinian natural selection.