Re: Forster's papers on Triceratops

[Ronald Orenstein <ornstn@inforamp.net>]

>  Would it make more sense to say that in an animal with a harem-type
>herding system, females would be more numerous >in herd situations<
>than males, unless they followed something along the lines of
>elephants with male herds and female herds?

>Betty Cunningham
>illustrator, animator, and likes to collect dead things

While I can't answer this directly, there is another aspect to the issue.
In many species with harem-type mating systems or lek-type polygamy, the
point is not that females outnumber males but that females and young males
outnumber adult males.  That is, acqusition of male secondary sexual
characteristics is delayed, often for years (for example, birds of paradise
can take four or five years to acquire full male breeding plumage, an
unusually long time for a songbird).  The reasons usually advanced for this
are that as the top males do the bulk of the breeding anyway, young males
would be at a disadvantage if they acquired characteristics that might
expose them either to increased predation or increased aggression from other
males before they could "put them to use" with females.

Thus is Triceratops had such a system (and who knows?), I might expect to
find a "male" morph outnumbered by a "female" morph which actually consists
of females and younger males.
--
Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
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