Determinants of Life History Variations

Studies of life histories of fishes are critical to both applied and fundamental science. The theoretical basis for consideration of life histories (sometime loosely referred to as “life history theory”) is relatively well developed with examples ranging from plants to invertebrate and vertebrate animals. Those theoretical considerations have given rise to a number of important predictions that have practical implications and applications. Those predictions range from sex ratio to age at maturation, fecundity, migration, and foraging for individuals and populations. That approach is generally focused on ultimate, evolutionary mechanisms (sometimes referred to as “why” questions). Despite the sophistication of our theoretical framework, studies of proximate mechanisms (referred to as “how” questions) are generally absent or seriously limited. For example, theory might predict that individuals should migrate in relation to potential growth in alternative habitats, but it does not predict the proximate cues to which the fish responds, or the linkage between proximate and ultimate mechanisms. In this symposium scientific colleagues from across North America, Japan, and Europe will present information about links between ultimate and proximate mechanisms from the level of genes and genetic activity to landscape ecology for both marine and freshwater fishes.