COMPARING LIFE HISTORIES USING PHYLOGENIES

The comparative method as recently developed can be used to identify statistically independent instances of life-history evolution. When life-history traits show evidence for correlated evolutionary change with each other or with ecological differences, it is often possible to single out the trade-offs and selective forces responsible for the evolution of life-history diversity. Suites of life-history characters often evolve in concert, and recent optimality models incorporating few variables show promise for interpreting that evolution in terms of few selective forces. Because hosts provide well-defined environments for their parasites, when host-parasite phylogenies are congruent it is possible to test ideas about the evolution of particular life-history and size-related traits.