Re: Theropod "migrations"

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

Berislav Krzic wrote:
> 
> However, I still have trouble in figuring out how meat eaters  moved on
> leaving behind their (conservative - "immobile") herbivorous prey, just to
> find eventual new prey "on the other side of the hill , across the desert,
> across the river", etc. 

Most carnivores tend to be extremely territorial, given the large
home ranges they tend to require. Colonisation of new areas could
have been the result of juvenile or older individuals being pushed
into marginal areas. If there is new territory to expand into
(such as a land bridge or island chain) then territorial animals
will probably end up filling the vacuum, whether they want to or
not. Such bottle necks ("less fit" animals) could also explain the
differences between ancestoral and migrant populations. So was
T.rex descended from "wimp" Tarbosaurs? Triceratops from "sissy"
protoceratopians?

-- 
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        Dann Pigdon
        GIS Archaeologist
        Melbourne, Australia

        Australian Dinosaurs:
        http://www.geocities.com/capecanaveral/4459/
        http://www.alphalink.com.au/~dannj
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