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RE: Dino coloration and more...



Betty Cunningham wrote:

>Zebras are 1) still hard to spot in their environment from a distance as   
>the stripes will blur their shape to a fuzzy grey.  It  works quite   
>nicely to hide zebras from human sight as well as color-blind animals.   
>and 2) the quagga (a striped zebra relative removed from existance by   
>the Victorian era) is now extinct by being predated upon by   
>color-perceptors that could see stripes from a closer distance just fine,   
>than you.

Er - not quite.  The observation about stripes blurring works for grevy's
Zebra but certainly not, in my experience, for the other two species - and
the current thinking is that the stripes are a social facilitator, not a
predator defence, at least in Plains Zebra (they like to stand next to
striped signs, for example - this has been tested).  As for the quagga - it
was unique among zebras in that it was, by and large, NOT striped.  Stripes
were confined to the head, neck and part of the forequarters.

>>It's interesting to note that very few predators have
>>high-visibility color schemes -- the coral snake is the first that
>>comes to mind, and that's defensive.
>
> I won't argue with you, but will mention wasps, spiders, and other   
>carnivorous insects that are brightly colored. And have other means of   
>defense other than looking colorful.

Not to mention fishes (like piranhas), many lizards and frogs (eg the large
horned frogs of the genus Ceratophrys).

>>Finally, since flowering plants didn't show up until the Cretaceous, I'd   
>>expect most creatures to be more in the drab shades until then.
>
>     Plants don't have to be flowering to be brightly colored.  The fall   
>coloration of decidous trees makes a very nice place for the red bat and   
>the red fox to hide in and they're amongst the brightest colored of   
>mammals

There is no reason to suppose that bright colours in animals are necessarily
linked to flowers (think of fishes, for example, or poison arrow frogs).
Further, there is no reason to suppose that non-flowering plants lacked
bright colours - besides leaves of many flowering plants, consider fungi
(yes, true, they aren't realy plants) or the cones of cycads, the arils of
some conifers etc.
--
Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
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