In a paper published this month in PLoS One, Elise Nowbahari, Alexandra Scohier, Jean-Luc Durand, and Karen L. Hollis reveal some exciting work in an oddly under-studied area - rescue behavior in animals. Humans clearly engage in rescue behavior, often to our own detriment, and we make complex decisions about whom we choose to try and rescue. You'd rescue your own kid. Would you try to rescue a cousin? A neighbor? A total stranger?
In this work, ants of the species Cataglyphis cursor were faced with a series of potential rescue situations, including:
- A trapped Cataglyphis cursor from their own colony
- A trapped Cataglyphis cursor from another colony
- A trapped ant from another species
- A trapped prey animal
- A trapped Cataglyphis cursor from their colony, chilled into inactivity
- No trapped animals
The results were quite specific: The ants only attempt to rescue active members of their own colony. They do this by digging away at surrounding sand, tugging on limbs (but not antennae!), and biting at the nylon snare trapping the ants.
This is fascinating work that brings up even more exciting future directions for research. As the authors conclude:
In sum, our findings establish that, in Cataglyphis cursor, rescue behavior not only is directed exclusively toward nestmates but also the nestmate must be active. Thus, rescue behavior necessarily depends on some form of actively produced eliciting stimulus, already known to be a pheromone in several ant species but one that contains a component unique to each colony.
What is the "help me" signal? Is that snare biting highly specific, or part of a general clearing of foreign matter from the problem area? How complex (versus, say, programmed) is this behavior?
I've also reposted their supporting videos to YouTube under PLoS One's Creative Commons license. They're worth a look:
You can read the original article by clicking here.