ananyo (2519492) writes "A species of termite found in the rainforests of French Guiana takes altruism seriously: aged workers grow sacks of toxic blue liquid that they explode onto their enemies in an act of suicidal self-sacrifice to help their colonies.
The “explosive backpacks” of Neocapritermes taracua grow throughout the lifetimes of the worker termites, filling with blue crystals secreted by a pair of glands on the insects' abdomens. Older workers carry the largest and most toxic backpacks. Those individuals also, not coincidentally, are the least able to forage and tend for the colony: their mandibles become dull and worn as the termites age, because they cannot be sharpened by moulting (abstract)."
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