Foxes That Endure Despite a Lack of Genetic Diversity
Marlene Breverman stashed this in Animal Genetic Diversity
The Channel Islands, off the coast of Southern California, are a natural laboratory for a particularly adorable experiment in evolution.
A unique species called the island fox has lived there for several thousand years, shrinking over the generations until now each is smaller than a house cat. Adult island foxes weigh as little as 2.35 pounds.
Now a team of scientists has discovered another way in which island foxes are extraordinary: Genetically, they are nearly identical to one another. In fact, a fox community on one island has set a record for the least genetic variation in a sexually reproducing species.
Oliver A. Ryder, the director of genetics at the San Diego Zoo Institute for Conservation Research, said the new research posed a biological puzzle.
It’s an axiom of evolutionary biology that low levels of genetic variation put species at risk of extinction. Yet the delicate island foxes are still racing across meadows and bounding up trees.