Rescuing a nestmate from a predatory antlion enables ants of Tetramorium sp. E to avoid antlions, Myrmeleontidae spp., in subsequent encounters
Tetramorium sp. E, commonly known as pavement ants, have shown the ability to rescue conspecifics as well as the capacity to learn. Given that pavement ants have these capabilities, the goal of the present study was to investigate whether an ant, after engaging in rescue behavior of a distressed nestmate captured by a predatory antlion, Myrmeleontidae, would learn to avoid the predator’s conical pit trap. Four different experimental conditions, including the presence or absence of an actual antlion in the pit during the test phase, and the opportunity to confront the same or a different pit, allowed us to test various explanations of how ants might avoid antlions. Both rescue behaviors and latency to fall into the antlion pit were analyzed. The results showed that, compared to ants that did not rescue nestmates, ants that engaged in rescue behavior subsequently tended to avoid antlion pits. This avoidance indicates that ants were able to learn about antlion pits to avoid them, which is important because in nature antlion pits occur very close together, so an ant that rescues a nestmate has to carefully navigate to get out of clusters of antlion pits, called pit fields. Furthermore, the dynamic between these two species, and their abilities to learn, lend insight into how they have coevolved and adapted over evolutionary time.