AppId is over the quota
AppId is over the quota
While gray and red squirrels are distinct species, black squirrels are not, said John E. McDonald, a wildlife biologist for the U.S. Fish and Wildlife Service's Northeast division.
"A lot of people think of them as a separate species from the gray squirrel. But they are gray squirrels, only a different color phase," he said.
Photo by David Molnar/The Republican Homer G. Perkins, who was on the board of directors of Stanley Park in Westfield for more than 50 years, holds a photograph of the park's carillon.
Gray and black squirrels do mate, said Marion E. Larson, a wildlife biologist with the state Division of Fisheries and Wildlife. The offspring can be either gray or black, and when two grays mate, the offspring can occasionally be black.
"And two black squirrels could produce black or gray colored squirrels," she said.
So why haven't black squirrels become as common as their gray cousins in this area? One reason is that the gene for black fur is recessive, meaning that it takes an uncommon pairing of parents to produce a coat of that color, Larson said.
As with all animals, including human beings, the features of the offspring are determined by the genes of the parents. A child gets genes from both its mother and father, and in some of those pairings of genes, one gene may be dominant, meaning it's the one that determines the feature, while another may be recessive, meaning that it gives way to the dominant gene. Only when two recessive genes are paired will the feature coded by that gene show up in the offspring. So it takes getting that recessive gene from both parents for the fur to be black. If either gene is the dominant gray gene, the fur will be gray.
Article excerpt via MassLive.com
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