Re: Repost on predation
Paul Crowley (Paul@crowleyp.demon.co.uk)
Thu, 23 Nov 95 14:56:13 GMT
In article <48tvsk$9ia@geraldo.cc.utexas.edu>
gator@mail.utexas.edu "chris brochu" writes:
> Paul@crowleyp.demon.co.uk writes:
> >Hunt what? Most prey will see them and run. Maybe from clear
> >waters crocodiles can catch prey at night, or grab desperately
> >thirsty or sick animals. But daytime hunting in clear waters
> >could not normally provide a means of sustenance.
>
> Then explain the large birds I've seen them catch in clear water in broad
> daylight. For that matter, I've seen film of C. porosus in clear water
> catch wallabies.
The only explanations that makes any sense to me are (a) the birds
were on migration and forced down to unfamiliar waters, or (b) that
this kind of predation was so unusual and unexpected that the prey
was not alert. What were the birds? ducks?
I stand by my general argument. Predators are not super-efficient.
Their fail much more often than they succeed. Lions do not
generally hunt by day, because the prey can see them and can run
faster. Crocodiles do not *generally* hunt in clear water by day
for the same reasons. They lie up in murky waters. Crocodiles do
not inhabit the Great Barrier Reef, nor lagoons in coral atolls,
nor the Red Sea - for reasons that should not need spelling out.
> >"Deposits in the region" are irrelevant unless they're actually
> >in that valley. And they're not.
>
> Actually, they are. Perhaps not submerged today, but within the rift.
The Red Sea Rift could have started a bit like the East African Rift
today - with some fresh water lakes. Although being so straight and
deep, it would have opened to the sea much more quickly. Any early
lakes would have had crocodiles. But we are looking at >30Myr.
Do you have information of the dates of the deposits?
Paul.
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