Why are some black bears brown?
American black bears are not all black. They come in brown, blonde, and blue-grey. The colour variations have genetic causes.
Mutation in the pigment gene
American black bears are not all black. They come in various colours, including brown, blonde, and blue-grey. New research findings have found the answer in the genome of the black bear: a mutation in the pigment gene TYRP1. The research was published in Current Biology .
Melanin is the pigment that gives mammals their coat colour. There are two types: eumelanin (black or brown) and phaeomelanin (red or yellow). The researchers found that cinnamon-coloured black bears produce lower amounts of eumelanin.
9’360-year-old mutation
The TYRP1R153C mutation arose spontaneously approximately 9’360 years ago in black bears in the western United States. “The TYRP1R153C mutation has likely given cinnamon-coloured bears an advantage in their current range,” says Dr. Puckett.
The research team proposes a new explanation: crypsis, the ability of an animal to conceal itself through colouration similar to its background. More on the topic of Wildlife.
| You can help all animals and our planet with compassion. Choose empathy on your plate and in your glass. Go vegan. |
More on the subject of recreational hunting: The scientific evidence is presented in the overview Studies on the Effects of Recreational Hunting.
The position of IG Wild beim Wild: IG Wild beim Wild rejects recreational hunting. Our model is the canton of Geneva, which has managed without recreational hunting since 1974: without hunting seasons, without hunting dogs, without driven hunts, without high seats, without the animal cruelty and crime that go hand in hand with hunting season elsewhere. What has worked there for over fifty years disproves every position paper by JagdSchweiz. An association that bases its policy on claims it refutes in its own documents is not a professional organisation, but a factory for misinformation.
