An ongoing study of the cause of death of howler monkeys on Barro Colorado has identified the howler monkey bot fly Cuterebra baeri as the single most important factor. Very young monkeys are the ...

They can use this tail as an extra arm to grip or even hang from branches—no Old World monkeys have such a tail. A gripping tail is particularly helpful to howler monkeys because they rarely ...

“But no, the truth is that babies are very delicate, they can’t be in a house where there are dogs or cats, because they have pathogens that can potentially be fatal for howler monkeys,” he ...

It’s so hot in Mexico that howler monkeys are falling dead from ... the agency said. The baby monkey business in the U.S., he says, is fueled by buyers who think the baby monkeys “are cute.” ...

My adventure of a lifetime began in 2015 when I was asked to follow the tree-top lives of Costa Rica’s gravity-defying howler monkeys (Alouatta palliata palliata). Image by Justine Allan.