California ground squirrels and rock squirrels chew up rattlesnake skin and smear it on their fur to mask their scent from predators, according to a new study by researchers at UC Davis.

Barbara Clucas, a graduate student in animal behavior at UC Davis, observed ground squirrels (Spermophilus beecheyi) and rock squirrels (Spermophilus variegates) applying snake scent to themselves by picking up pieces of shed snakeskin, chewing it and then licking their fur.

Adult female squirrels and juveniles apply snake scent more often than adult males, which are less vulnerable to predation by snakes, Clucas said. The scent probably helps to mask the squirrel's own scent, especially when the animals are asleep in their burrows at night, or to persuade a snake that another snake is in the burrow
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