In the early 1960s, biologists Carl and Marian Rettenmeyer began a decades-long study of army ant colonies in Central America. One major focus of their work was the abundance of mites, lice, beetles, and other invertebrates that live symbiotically with the ants, either in their nests or on the bodies of the insects themselves. The Rettenmeyers discovered many new and fascinating species, such as a mite that takes the place of an ant’s foot and feeds on its blood, or other mites that live solely on an ant’s eye or…