Ants defend African savannah against hungry elephants

Science Daily - Ants take on Goliath role in protecting trees in the savannah from elephants

The East-African savannah houses a variety of herbivores and the elephant plays a significant role in its deforestation. As the drought-prone region becomes more so due to global warming, there is a risk the region will be converted to grassland from savannah as hungry elephants eat most of the trees. Researchers observed that elephants largely avoided one species of tree, the Acacia drepanolobium, though in a nursery with controlled conditions ate it as freely as other species. In the savannah, the tree houses colonies of ants, who use its cover and feed off its nectar. The ants aggressively swarm animals that get near the tree, and in the case of elephants, crawl up their trunks and bite the insides. Ants weren't able to affect the giraffe as easily, which uses its tongue to swipe away the ants. But the ant/tree defense against the elephant was shown to play a role in keeping trees in the savannah while other trees were eaten. It appears the elephants know to avoid the trees due to smelling the ants, which raises the possibility of using an ant-odor to repel elephants from human crops.