I was just reading over another recent paper that may also prove relevant to this post as well as the previous one, so I thought I would post an update.
Site fidelity in cetaceans is not new, but a recent paper by Valenzuela et al (2009) does an excellent job showing that for at least some large mysticetes, site fidelity is a matter of cultural inheritance, and can cause a lack of flexibility (at least in the geologically speaking 'short term') of feeding grounds for some taxa even in bad years.
Obviously, this report does not bode well for balaenids in the oncoming global warming situation, though it may be another facet worth exploring when considering prehistoric cetacean distributions. It may ultimately be outside the realm of possibility to answer such questions, particularly when we still don't have good estimates of simple things like body size of fossil groups (though I know one person is working on that) or how far different taxa may have regularly migrated (which may or may not be consistently related to body size).
FOSSIL SITES OF THE OKANAGAN HIGHLANDS
21 hours ago
Certainly from the middle Miocene to the late Miocene/early Pliocene there are some interesting trends with mysticetes. There is a dramatic drop in diversity along with a simultaneous increase in body size. I don't know if these two trends are related, but I've long suspected that they may be related to the climate changes at the same time.
ReplyDeleteI suspect that the work Nick Pyenson did during his dissertation might be useful in getting at this. I don't know when the papers from that will be out, but I hope he gets some of the body size estimation work out soon.
ReplyDeleteI wonder, perhaps with some other faunal details (including micropaleo), do you think a better understanding of the water temperature could be estimated for some of these localities? It might take a coordinated effort of many people, but it would be worth doing.
Some micropaleontology should definitely help, ideally at least some of the sediment surrounding a fossil should be saved for such an analysis. And like you mention it should be coordinated by several people, it is a lot of work for one person, I've tried doing it, but after a while I realized looking for tiny invertebrates was not my favorite thing to do.
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