Do blue jays use ants as deodorant? It was once hypothesized that blue jays (and other jay species) would use the formic acid from ants to clean their feathers of parasites or as a form of chemosignalling. However, a study in Chemoecology tested this hypothesis by providing jays with ants with or without formic acid. Turns out that blue jays manipulate the ants to remove the bitter taste of the formic acid, allowing them to now eat a food source that was unpalatable before! So although the self-cleaning hypothesis was debunked, we can imagine a world where blue jay marketing still tries to sell ant acids as deodorant! 

Sketch and fact contributed by Victoria Farrar

Source: Eisner, T. & Aneshansley, D. (2008). “Anting” in blue jays: evidence in support of food-preparatory function. Chemoecology, 18(4), 197-203. doi:10.1007/s00049-008-0406-3