Sand fiddler crabs that reside in a burrow usually prevail if challenged by another, intruding crab, provided their claw pinching strength is similar to that of the competing crab, a study suggests.

Burrowing owls aren’t your average owls: They don’t live in trees, and they’re not nocturnal. They make their nests underground — usually in abandoned rodent burrows — and are active both day and ...