The Case of the Human Bone

Cemeteries are known locations of an abundance of human bones. But cemeteries are not the only site where human bones have been deposited, in both modern and ancient times, and investigations of such bones, wherever they are found, can often tell us a lot about traumatic injuries, environmental changes, cultural histories, and a number of other phenomenon that might interest anthropologists, including forensic anthropologists. However, interpreting bones can be difficult. Various destructive factors can change the shape and other features of bones over time, and thus the more we know about processes of bone destruction, the more we can know about the other phenomena associated with the bones.

And here’s where the ants come in. A paper published earlier this year, in Forensic Entomology, formally reports a discovery that previously had only been the subject of speculation and anecdotes: direct modification of human bones… by ants.

Right ankle joint with ant damage, from Figure 4 in Go (2018)

The researcher, UIUC doctoral candidate Matthew Go, discovered the bones from an individual interned at a public cemetery in Manila, Philippines. It turns out that this 80.6-year-old male was blessed in the afterlife, as his bones served as a postmortem home for premortem ants! These ants, in the genus Nylanderia, appear to have created, and/or expanded, holes in the bone, as evidenced by “minutely scalloped edges, with some holes displaying radiating shallow striae, possibly due to ant gnawing” (Go 2018, pp. 119-120). Go suggests that the damage done by the ants to these bones resembles that of a caterpillar feeding on a leaf, and that the possibility of the ants using their formic acid alongside this chewing behavior “should be considered”.

Thus, at long last, anthropology is made worthy of its name.