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| Although the role that Pleistocene glacial cycles have played in shaping the present
biota of oceanic islands world-wide has long been recognized, their geographical,
biogeographical and ecological implications have not yet been fully incorporated
within existing biogeographical models. Here we summarize the different types of
impacts that g lacial cycles may have had on oceanic islands, including cyclic
changes in climate, shifts in marine currents and wind regimes and, especially,
cycles of sea level change. The latter have affected geographical parameters such as
island area, isolation and elevation. They have also in?uenced the con?gurations of
archipelagos via island fusion and ?ssion, and cycles of seamount emergence and
submergence. We hypothesize that these sea le vel cycles have had signi?cant
impacts on the biogeographical processes shaping oceanic island biotas, in?uencing
the rates and patterns of immigration and extinction and hence species r ichness.
Here we provide a ?rst step toward the development of a glacial-sensitive model of
island biogeography, representing the tentative temporal evolution of those bio-
geographical parameters during the last glacial cycle. From this reasoning we
attempt to derive predictions regarding the imprint of sea level cycles on genetic,
demographic or biogeographical patterns within remote island biotas. | |
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