These vocal primates are the biggest of all the New World monkeys. Unlike Old World monkeys, howlers and other New World species have wide, side-opening ... helpful to howler monkeys because ...

The monkeys' "ultra-yodels" had frequency leaps that were five times larger than human frequency changes, often exceeding ...

Lisa Corewyn, associate professor in the Department of Biology and coordinator of the anthropology minor at Ithaca College, ...