Why do squirrels in different places have differing coloring ?? Ex. USA EAST - GREY, Canada - black?

In Council Bluffs Iowa they have 3 kinds. Black Grey and red. In Minnesota they have flying squirrels. It is just where they have been introduced into those areas and have thrived. Squirrels can't buy airline or bus tickets to travel so they are where they are unless humans intervene and move them which they do from time to time. That's how the black squirrel got to Iowa.Why do squirrels in different places have differing coloring ?? Ex. USA EAST - GREY, Canada - black?
Because there are different species all over North America, end their areas overlap given you the sense they are just a single species. There are local color patterns in different areas, and changes due to evolutive reasons, giving some individuals advantages over neighbors with a color not so well suited.Why do squirrels in different places have differing coloring ?? Ex. USA EAST - GREY, Canada - black?
There are different species of squirrels. The ones where I live are gray and there are some that are brown.
I grew up in southern ontario and the Eastern grey squirrel (Sciurus carolinensis) has two color phases there, grey and black (same species, just different coat colors). It has a wide distribution in the east of NA.


http://www.unity.edu/webdesign/tmorgan/s鈥?/a>


The eastern fox squirrel (Sciurus niger) also has a broad distribution in the east.


http://www.discoverlife.org/nh/tx/Verteb鈥?/a>


It is more brown in color, and at least where I am in Texas is smaller than the grey squirrels in Ontario, but that may just be a latitude difference. I have not seen grey squirrels here, apparently they are more common in east Texas.





In terms of why there is the color polymorphism in the eastern grey squirrel, I have never seen a study that tried to explain it, though I haven't looked carefully (try google scholar). I don't think it causes nonrandom mating (grey with grey, etc) but I may be wrong about that. There may be a selective difference that varies over geographical area.
Evolution! I am not positive that the squirrels in different areas of the country are actually different species, as many species of animals like the ';grey'; squirrel have been misnamed before. Humans have many different hair colors, but we are all the same species. However, you see certain combinations in certain environments as a result of natural selection. Very fair-skinned people in Africa or the Middle East would be susceptible to sunburns and skin cancer, and might even be easier to spot against dark sand and dirt. Therefore, you see fair-skinned Scandinavians, dark-skinned Middle Easterners, and almost black-skinned Africans. The very homogenous look that Asians have is largely due to geographic isolation (ie Japan).





Evolution drives variation different ways. For example, in the eastern US any squirrels that are black might be immediately more noticeable to predators and the black coloration is therefore evolutionarily less favorable. Perhaps the same is true for grey squirrels in Canada. Or, to make things even more compliated, maybe there's genes linked to coat color. Even if grey squirrels are EASIER for predators to spot than black squirrels, they may still dominate an area. Maybe certain immunities are associated with being grey. Let's say grey squirrels are resistant to parasite or disease X, and disease X is present in the eastern US. Grey squirrels will therefore be infected less and could have more grey offspring than black squirrels have black offspring (disease often lowers reproductive output). However, in Canada, this disease may not be present, so the advantages conferred by not being seen by predators outweighs the lack of immunity.





Evolution and genetics is an endlessly fascinating (and complex) subject. To me at least! :)
Many things can influence different coloring in types of squirrels, such as geographic isolation, or the environment in witch they live in. Coloration may also assist in attracting a mate??? I'm no expert, but I know a little bit about them.
Probably has something to do with the color of their surrounding environment. They would evolve different fur colors to blend in.