Re: Dinosaurs vs. mammals: a hypothetical scenario

[Dann Pigdon <dannj@alphalink.com.au>]

On Fri, Apr 8th, 2011 at 1:05 PM, Augusto Haro <augustoharo@gmail.com> wrote:

> Perhaps large mammals would be very challenged by the larger
> dinosaurs, with faster reproductive and growth rates. In addition to
> competition with herbivorous dinosaurs, they would suffer predation
> they were not adapted to deal from large theropods.

Unless mammals indulged in 'egg feasts'. I doubt there were any mammals in the 
Mesozoic that 
could dig up a dinosaur egg and carry it off while the parents were otherwise 
distracted. The 
dinosaurs may have had an initial advantage in this hypothetical scenario, but 
if their reproductive 
success was severely compromised then it would only be a matter of time before 
the balance 
swung back in favour of the mammals. 

Look what happens when even small mammals like rats or mice are introduced to 
islands where 
birds have no experience of mammalian carnivores - bird numbers tend to plummet 
dramatically. 
Introduce a single cat to a small island and it can wipe out an entirely bird 
species in short order. 
The dinosaurian behavioural repertoir would most likely not have included 
appropriate responses 
to large mammals, so they may have been in a similar situation to that of 
modern birds that 
evolved on mammal-free islands.

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Dann Pigdon
Spatial Data Analyst               Australian Dinosaurs
Melbourne, Australia               http://home.alphalink.com.au/~dannj
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