Re: Triceratops

[Brian Choo <bchoo@cyllene.uwa.edu.au>]

Steve  Brusatte wrote:
>I find it hard to believe, in a strict biological sense, that four
>different species of the same genera would inhabit the same area.  I do
>know that some of the Psittacosaurus species are from different times, but
>this notion is still hard to believe.  Dodson, in his book, repeats the
>fact that there is only one species of giraffe, one species of hippo, and
>one species of rhino in Africa today.  If there were 8 or 10, then all of
>the species would be competing for the same general foods and something
>would go extinct.


Well, such a high diversity of one species is unusual but far from
unprecedented. Using extant macropod marsupials as an analogy, the
following species of Macropus (large grazing wallaby/kangaroo species -
similar in size or larger than Psittacosaurus) can be found in
warm-temperate east-coastal Australia, not always co-habiting but present
in the same general region...

Macropus agilis (agile wallaby), M. dorsalis (black-stripe wallaby), M.
giganteus (Eastern Grey Roo), M. parryi (Whiptail Wallaby), M. robustus
(Wallaroo), M. rufogriseus (red-necked Wallaby).

Similarly diverse collections of this genus can be found in other parts of Oz.

A more impressive but perhaps less relevant example: A single stretch of
Indo-Pacific coral reef may contain over thirty species of Chaetodon
(invert-grazing butterflyfish)


Cheerio
Brian