On Sat, 3 May 1997, Barry Cadwgan wrote:

Based on my minimal knowledge of biology, it would depend on whether the
animal in question is nocturnal or a carnivore vs herbivore.

The Rods are the light/dark sensors and are much more sensitive in low
light, so night creatures will have more and so minimal if any colour
vision.  Predators like big cats also have a lot of rods, as it makes
camoflage less effective (I seem to remember that is the reasoning
anyway)

Herbivores and omnivores tend to need good colour vision to be able to
identify their food.  It would be important to be able to distinguish
between green and ripe fruit _before_ you eat it.

Actually, among carnivores, it would also depend upon the manner in which
they hunted. For instance, lizards and some birds have good color vision.
This is because lizards and birds are sight hunters, relying much less
upon hearing or smell than mammals do. Also, since all mammals were
initially nocturnal some time along the evolutionary line, sight really
took a back seat to the other senses. There are some notable exceptions,
such as african cheetahs which have adapted to be sight hunters...(also
lost the rectractable claws too, i think. Needed to grip the ground
better, i guess...)

Herbivores and ominivores do not necessairily have good color vision, as
most fruits can be distinguished in ripeness by smell, although you are
correct about one particular branch of mammals. Primates, on the whole,
rely much more on vision than the other mammals. Probably the reason that
they have large brains, as complex visual information is difficult to
process and interpret. Still, on the whole, i'd agree that herbivores/
omnivores would have better color vision than carnivores, as color vision
generally goes hand-in-hand with visual acuity, and most of the things
that herbivores eat don't draw attention to themselves by trying to run
away...

In the case of the pig, i would go with the increased rod count, giving it
reasonably good, if grainy, night vision, and very low color recognition
ability, as i think that boars are mostly nocturnal, aren't they? This is
all conjecture, as i'm not even drawing on biology, but rather, some
cursory knowledge of physical anthropology, and lots of wildlife
shows...

~Eimii