Amphipoda

Abstract

The biology of amphipods that inhabit inland waters is reviewed. Topics considered include biodiversity, evolution, geographical and ecological distribution, diet, behavior, population dynamics, life histories, ecological interactions, environmental tolerance, and use as bioindicators. A comprehensive, topical list of sources on these and other aspects of amphipod biology is provided in an appendix table. Amphipods are important components of many aquatic ecosystems, especially in Temperate Zones where they are often the most abundant macroinvertebrates in alkaline springs, spring-fed streams, and subterranean waters. Their generalized feeding habits and high food quality contribute to the major ecological impact that they make in habitats where they are abundant. Amphipods brood their offspring and often engage in precopulatory mate guarding, behaviors that facilitate studies of life-history evolution, and sexual selection. Many amphipods live in isolated aquatic habitats where they often exhibit considerable population differentiation that has often led to the evolution of unique local species. In caves, amphipods have evolved troglomorphic adaptations, including loss or reduction of eyes and body pigment. Swarms of amphipod species have evolved in some deep lakes. The diversification of amphipods in Lake Baikal of Siberia represents one of the most spectacular examples of adaptive radiation in the animal world. Recently, many species of amphipods have expanded their geographical distribution, often as a result of human activity. Invasive amphipod species are impacting numerous freshwater ecosystems, especially in Eurasia and North America. Furthermore, amphipods are frequently used as bioindicators of pollution and other environmental stressors in a variety of aquatic ecosystems.