Extinction threatens 60 percent of primates

From gorillas to gibbons, about 60 percent of primates, the closest biological relatives to human beings, are threatened by extinction due largely to human activities, a study has found.

"This truly is the eleventh hour for many of these creatures," said Paul Garber, anthropology professor at University of Illinois, who co-wrote the study published on Wednesday.

Researchers also reported that around 75 percent of primate species have declining populations.