EVOLUTION OF LIFE-HISTORY PATTERNS IN THREE GENERA OF SPINY LOBSTERS

摘要

The life-history patterns and probable evolutionary pathways of three extant genera of spiny lobsters are compared. The deep-water genus Palinurus and the shallow-water genus Panulirus are members of the Stridentes (sound-producing) lineage, while the cool-temperate shallow-water genus Jasus belongs to the Silentes group. The Stridentes and Silentes lineages evolved independently for over 150 million years, yet species of the two lineages still share a number of common characteristics, including a lcng-lived phyllosoma larval phase and remarkably similar adult morphology. Species of the two shallow-water genera, Jasus and Panulirus, differ from each other, and from the deeper-water Palinurus species, in certain aspects of reproduction. A post-Miocene shift from deep to shallow waters in the former two genera has apparently been accompanied by changes in mechanisms of fertilization and increased egg production. These adaptations are likely to have evolved in response to higher natural mortality rates and greater environmental variability in shallower waters.