Chimps help Lincoln Park Zoo vet study their hearts

1 of 6: In this May 7, 2012 photo, primate caretakers, from left, Cindy Swisher, Jill Moyse, Maureen Leahy, and veterinarian Dr. Kathryn Gamble, check the heart of Keyo, a 54-year-old chimpanzee at the Lincoln Park Zoo in Chicago. Eight chimps at the zoo have had small heart monitors implanted and so far three of the animals have been trained to present their chests to a scanner to upload data from the monitors. (AP Photo/M. Spencer Green) (AP Photo/ M. Spencer Green)

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