While you probably saw many Cleveland Metroparks Zoo visitors glued to their cell phones this summer, you might not have realized that some were burning their minutes to learn something. This summer, the zoo launched an audio tour, available by calling (216) 453-3962 and punching in numbers displayed on signs throughout the zoo. Admit it, you want to know how far a polar bear walks in its lifetime (more than 9,000 miles) or which chase-but-won’t-kill breed of dog is used in Namibia to defend livestock from cheetahs (the Anatolian shepherd). The initiative aims to educate visitors about animal conservation. The zoo says around 2,600 people called during the program’s June and July launch.