RE: mosasaur babies/no marine dinos

[Ronald Orenstein <ornstn@rogers.com>]

At 07:22 PM 01/01/02 -0800, Tracy L. Ford wrote:
> A related phenomenon is the distribution of penguins.  Given their great
> fishing ability, they should be competitive in all parts of the world.  But
> their distribution is primarily southern.  I believe nest sites are the
> limiting factor here; that is, nest sites and predator abundance--which
> amounts to the same thing--nest sites without predators are much more common
> in the Southern H. than the Northern.

Penguins actually have a broad latitudinal range, from the Equator (the 
Galapagos Penguin) to the coast of Antarctica.  They may have been excluded 
in the north not by predators (after all, one of the world's largest 
penguin colonies is on the Valdez Peninsula of Argentina which is certainly 
not predator-free, and Black-footed Penguins nest on the mainland of South 
Africa where they face heavy predation by genets - not to mention predation 
at other sites by skuas and caracaras) but by the presence of the 
convergent auks (including the extinct flightless Mancallid auks of the 
Pacific Coast).  There are certainly plenty of seabird islands in the 
Northern Hemisphere, some with huge populations (eg the Pribilofs), and in 
its heyday the extinct and flightless Great Auk, which was quite 
penguin-like, had large breeding colonies at numerous sites on both sides 
of the North Atlantic.


--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court
Mississauga, Ontario, Canada L5L 3W2          mailto:ornstn@rogers.com