Its a gibbon, Siamang (Symphalangus syndactylus), kept captive in Los Angeles Zoo. This tail-less, black-furred primate has been brought from its native Sumatra. We were amused to hear a loud resonating call produced by it. As I probed the net, found the sound was emanated due to the inflatable gular pouch at the throat. It was sad, due to poaching for pet trade and extensive habitat loss, this primate is in IUCN's endangered list.