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Re: On predation.
Bill Burnett (bbur@wpo.nerc.ac.uk)
Thu, 2 Nov 1995 10:00:44
(H. M. Hubey) writes:
>chris brochu <gator@mail.utexas.edu> writes:
>>Miocene, they must have used transoceanic routes for dispersal. There is
>>no other way to explain their presence in South America, Africa, and
>>Australia.
>The case for Ausralia is believable because aborigines did
>something similar. It's hard for me to believe crocs swimming
>across the Atlantic. If it wasn't a freak accident of some
>croc surviving for a year or so while the current drifted it over,
>it's hard to see how else it could have happened.
Actually the Australian aborigines entered the continent via a land bridge
from PNG somewhere between 40000 and 100000 years ago, depending on who you
talk to, the evidence for the later date is (I think) from a deep core from
the southern Great Barrier Reef which indicates a change from deciduous to
fire tolerant eucalypt forests with the arrival of fire using humans. I was
fascinated by this, does anyone know more? (Oooh, could be a non AAT s.a.p.
thread???)
Saltwater crocodiles have been observed swimming happily several hundred km
from the mainland, they can be expected to cross the Torres Straits reasonably
easily (IMunsupportedO). We were always way more scared of them than we were
of sharks when working there (just through the horror factor...), I'll stay
in the water with most warm water sharks (tigers excepted) but crocs...
noooo! You're right though, the trans-Atlantic thing seems unlikely but I
didn't see the original post... again I'd love to know more. I can say that
crocs in Australia are undergoing a boom now that hunting pressure is way
down, and they seem to 'reinfest' areas (ugly word, they're _supposed_ to be
there) very rapidly, and have no trouble crossing dry areas between river
systems. BUT as I've said before, the pro and anti-AAT predator threads are
both way out of proportion, personally I don't think they'd be that important.
Bill
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