It’s International Bat Week! These animals are an incredible success story: of the 5,400 known living species of mammals, more than 1,000 are bats. The one pictured here is the infamous vampire bat, named because of its spooky feeding habits: these bats often crawl undetected onto the bodies of their sleeping prey to bite them and sip their blood. But unlike in a horror film, vampire bats rarely kill, and their “victims” (typically birds or livestock) seldom realize they’ve been bitten.