Orangutans are known for an impressive feat of engineering: They carefully weave an intricate nest from branches and leafy twigs in the forest canopy daily, building and rebuilding for cozy nights and shady midday naps. Some nests, particularly those made by older and more experienced orangutans, feature pillows, linings, blankets, and sometimes even a roof fashioned from broad leaves—and all must be well protected from the elements and strong enough to hold 100-plus pounds of slumbering ape. Now a study published in Animal Behaviour reveals that young orangutans perfect this vital task over the course of seven years.
"The fact that it takes them so long to acquire this skill shows us that it's much more complex than we realized before," says the study's lead author Andrea Permana, a primatologist at the University of Warwick in England. To understand this behavior, researchers followed 45 orangutans at Indonesia's Gunung Leuser National..
. Sierra Bouchér.
