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Re: Forty years of predation on Serengeti.



On Wed, 24 Sep 2003, John Bois wrote:
> Important paper with some relevance (perhaps) to dinosaurs: Sinclair,
> A.R.E., Simon Mduma and Justin S. Brashares 2003 Patterns of predation in
> a diverse predator--prey system. _Nature_ Vol 425, pp.288-290.
> Concludes that smaller prey are target of diverse predators (many preying
> opportunistically) and are limited by predation.  Larger prey--at a
> threshold of around 150 kg (e.g., giraffes, rhinos, and elephants)--are
> somewhat immune and are instead limited by food availability.  Rhinos and
> elephants suffer almost no predation and even their juveniles are prey
> "only rarely".
> 
> This must be a huge contrast with dinosaurs--even very large
> dinosaurs--whose very small juveniles must have been fodder for diverse
> predators.  Because of this, Mesozoic ecosystems were entirely different;
> reproductive dynamics, pred/prey ratios, etc., etc.
> 
> Interesting that when, during time of heavy poaching predators were
> removed  from Serengeti system, numbers of small prey went up...but large
> animals remained limited by food supply!  How does this affect the vaunted
> advantage of large size: ability to process large quantities of food?
> I mean, who cares if one can process vast amounts of
> food, if vast amounts of food are unavailable?  One would have to argue
> there was more food in the Mesozoic.  Otherwise, like the elephants,
> predator-resistance seems its prime value.
> 
> Enough rumination.

Just out of curiousity, wouldn't predator teeth show more effects from
crunching parge bones than small ones? Is such usage detectable?