If you take a look around the lush forests, green wetlands, and tranquil suburbs of Toronto, it’s no doubt you’ll find black squirrels around. They may even seem to be in the majority, outnumbering grey and red squirrels.
But the fact of the matter is, black squirrels are the same species as the eastern grey squirrel. They can even mate with each other. The only major difference is their colour. So why do black squirrels look black?
Research conducted by scientists in 2014 found that black squirrels are just grey squirrels with two types of pigment genes that cause their fur to become jet black. This genetic mutation likely arose from interbreeding with the fox squirrel, which has a similar mutation in its genes.
Differing from grey squirrels, which have only one of these pigment genes, being a black squirrel may offer an evolutionary advantage as well.
During the cold Toronto winters, black squirrels will retain heat better than their grey cousins. They also have been reported to have more testosterone than their grey counterparts, attracting females more. However, this research is yet to be verified.
Black squirrels are so common in Toronto that they were requested to be shipped to the National Zoo in Washington, D.C. over 100 years ago due to their assumed rarity. Nowadays, Washington D.C. is also overrun by black squirrels.
Toronto citizens may feel that black squirrels aren’t special at all. However, it’s no doubt that many visitors to Toronto are surprised to see black squirrels.