Why Crows Cover Themselves in Ants
Crows and many other birds deliberately cover their feathers with ants, a behavior called anting, but scientists still do not know exactly why.
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Some birds have a surprisingly strange grooming habit: they deliberately put ants on their bodies. This behavior is known as anting, and it has been observed in more than 200 bird species. Birds may pick up ants and rub them through their feathers, or they may settle on or near an ant colony and let the insects crawl over them. Crows have been photographed doing this in a particularly striking way, with one bird spreading its wings and allowing ants to cover its feathers. Scientists have several ideas about why birds do it, but there is no single confirmed explanation. One leading possibility is that birds are taking advantage of chemicals released by ants for defense. These chemicals may have effects against some insects, mites, fungi, or other organisms. Another possibility is that the chemicals provide a soothing sensation during molting, when birds replace old feathers and their skin can become irritated. Other proposed explanations include grooming, preparing insects before eating them, or simply enjoying the physical sensation. Research has not settled the question. Experiments have found that the specific ant chemicals tested do not always produce the parasite-killing effects that might be expected, so the common idea that anting is simply a form of self-medication remains uncertain. The behavior is therefore a good example of how scientists can observe a repeated animal behavior while still lacking a definitive explanation for its purpose.
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