| Popis: |
The equilibrium theory of island biogeography may be viewed in both ecological and evolutionary time. The isolated Hawaiian Archipelago is at the outer limit of the dispersal range for land bird taxa. Thus, autochthonous speciation has exceeded the rate of immigration from outside the archipelago, leading to high endemicity. The endemic family Drepanididae has achieved species-area saturation through adaptive radiation in evolutionary time. Varia- tion in island area accounts for 99% of the observed variation in species diversity within the archipelago. An equilibrium situation is further suggested by the slope of the species-area relationship which conforms to theory. Pleistocene changes |
