Watch these African ants treat comrades injured on the field of battle

Ants may seem expendable, especially when colonies swarm with thousands of individuals. But Africa’s Matabele ants (Megaponera analis) go out of their way to save nest-mates injured on the field of battle. The sub-Saharan ants have a strict termite-only diet, and some of their ranks sustain injuries when they conduct raids to capture and kill the insects. Last year, a study found that after each raid, Matabele ants carry comrades with nonfatal injuries back to the nest. Now, a new study shows that their heroism extends even further. Scientists excavated six Matabele ant colonies and brought them back to the lab. Some ants were experimentally wounded by pulling off two of their legs, which triggered healthy nest-mates to haul those individuals back to the colony’s artificial nest. Once there, healthy ants cleaned the open wound with their mouth for up to 4 minutes at a time, the team reports today in the Proceedings of the Royal Society B. Most of the treated ants—90%—survived for 24 hours, but only 20% survived if researchers prevented them from being groomed by nest-mates. It’s not clear what the grooming does exactly, but the researchers think the ants clear away dirt and apply antimicrobial chemicals to the wounds to guard against infection.