Symbiotic ants defend acacia hosts from elephants

In the savannas of East Africa, tiny symbiotic ants depend on an acacia tree to provide them with housing and food. In return, the ants provide protection to the tree from the world's largest terrestrial herbivore, the African elephant. How can these tiny ants provide effective defense from an animal that is a billion times more massive? Watch the video to find out! Check out the paper at http://www.cell.com/current-biology/f.... And read more great research at http://www.cell.com/current-biology/home.