Add Yahoo as a preferred source to see more of our stories on Google. As our closest non-human relatives, primates remain some of the smartest creatures in the animal kingdom. And they continue to ...

If you liked this story, share it with other people. New research based on more than a decade of field observations indicates that wild Sumatran orangutans balance their sleep needs much like humans ...

The orangutan can be seen carefully making his way along the rope structure, which was put up two years ago to provide the ...