Abstract: This book explores the Trinidadian guppy's unique contributions to evolutionary ecology. Ever since Caryl Haskins — working in the 1940s and 1950s — described guppy populations as a natural laboratory because of the way predation pressure varies over a small geographical area, generations of researchers have been drawn to Trinidad to investigate evolution in the wild. The species continues to provide classic examples of natural selection in action, and elegantly illustrates how ecology, evolution, and behaviour are interlinked. This account of the evolutionary ecology of the guppy integrates historical breakthroughs with new research in this fast-moving field. It reveals how guppies provided some of the first evidence of sperm competition and sexual selection, and how they continue to inform scientific thought on mating systems and cryptic choice. The consequences of variation in predation risk — as well as a host of other biotic and abiotic factors — are described and evaluated at all life stages from conception to death. The book discusses behavioural responses to ecological conditions and examines life history evolution. The potential for ecological speciation is considered alongside new insights into how reproductive isolation becomes established in promiscuous mating systems. Conservation issues are also highlighted, both in terms of protecting the irreplaceable Trinidadian guppy systems and in the context of invasion ecology.

Keywords: natural selection, evolution, freshwater fish, tropical ecology, predation risk, sexual selection, reproductive isolation, Trinidad