(Exhibit 617) - Birds engage in a behavior called anting, where they allow ants to crawl on them or rub ants on their feathers and skin: Passive anting: The bird fluffs out its feathers, probes its bill into an ant nest, and then sits on the mound to let the ants crawl on it. Crows are known to use this method almost exclusively. Active anting: The bird picks up ants in its beak and rubs them on its feathers. The reasons why birds ant are not fully understood, but some theories include: Parasite