HANKIES at the ready. Heroic Brazilian ants wander off to die after sealing in their colony at night – the first time insects have been seen sacrificing themselves in the absence of a direct threat.
Adam Tofilski of the Agricultural University of Cracow, Poland, and his colleagues examined Forelius pusillus colonies in São Paulo, Brazil. They found that up to eight ants per colony locked themselves out by kicking sand over the entrance to hide it from predators (The American Naturalist, DOI: 10.1086/591688).
The behaviour is unique to this situation, suggesting the ants were not just late stragglers. However,…
