Gibbons are arboreal animals which means that they spend the majority of their lives in the trees. Living in the trees has it's advantages for the gibbon as the gibbon has plenty of food and is also a safe distance above ground from predators. read more
The gibbons spend much of their lives on tree branches 60 to 100 feet off the ground. But when they spotted the models, which were usually just a few feet off the ground, they descended to within 15 or 30 feet of the predators and sang at them. read more