[extropy-chat] Bowhead Whales May be the World's Oldest Mammals
robert.bradbury at gmail.com
Fri Mar 30 19:26:00 UTC 2007
On 3/28/07, Russell Wallace <russell.wallace at gmail.com> wrote:
> The two kinds of mammals I previously knew of with anomalously long
> lifespans are bats and humans, and in both cases the reason is slow
> reproduction creating a selection pressure for long life. Do bowhead whales
> reproduce unusually slowly for some reason?
To the best of my knowledge all long-lived mammals tend to be K-selected
(long pregnancy periods, long nurture periods). But it may be difficult to
disentagle this from the survival advantages of social groups and
intelligence which are semi-independent vectors enabling the evolution of
longevity. Fascinating that I'm sitting here staring a report (Hakeem, AY
et al 2006) on NMR studies of African elephants and they are citing "an
unusually large and convoluted hippocampus compared to primates and
especially to cetaceans". Given a several hundred year history of
slaughtering elephants, I question whether humans should ever enable a
direct elephant to independent "moral" robot link.
Slow reproduction and fewer offspring go hand-in-hand with K-selection which
is associated with putting more resources into single offspring because the
individual hazard function is lower. For R-selected species the hazard
function is higher, esp. for uneducated young'ns, so its a case of simply
crank em out and let the chips fall where they may.
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