Fossils show that howler monkey ancestors were eating leaves 13 million years ago, shaping body size and evolution.

The “big truck, small man” phenomenon is also seen in the animal kingdom. The loudest howler monkeys were found to have the smallest packages. Hyoid bone size, which is responsible for vocalizations, ...

An extinct relative of the howler monkey may have been the first leaf-eating primate in South and Central America ...

In southern Mexico, the deep and raspy roars of howler monkeys reverberate through the lush jungles enveloping the city of Comalcalco. The sound — akin to the rumble of distant thunder or the grumble ...

Part I. Introduction. 1. Why is it important to continue studying the behavioral ecology and conservation management of howler monkeys? / Martín M. Kowalewski, Paul A. Garber, Liliana Cortés-Ortiz, ...