[Taxacom] Pacific biogeography

[Karl Magnacca]

Jason Mate wrote:
> The email feels like it was meant for someone else. Although our
> improved understanding of the geological history of the Pacific has
> helped to solve some problems (i.e. taxa older than the islands they
> currently inhabit) it is not very clear to me how seafloor
> subsidence (a well known phenomenon BTW) would significantly alter
> the biogeographical status quo or how this can be invoked to support
> panbiogeographical theories. Any ideas?

In short, they wouldn't alter it at all.  In addition to what others
have said about seafloor subsidence, the seamounts that Michael is
referring to (mainly the Musicians and extensions of the Line
Islands) all date to 50-120 million years ago.  So even if he is
correct that they were ever high islands, 1) the emergent Hawaiian
island at the time would have been around Suiko in the Emperor
chain, not much closer than the Marquesas are to the current
Hawaiian Islands or even further; and 2) this predates the period
before Kure around 30 million years ago, when there were no high
islands and probably no emergent islands in the Hawaiian chain at
all.

Karl