>Very simply, animals learn to avoid such insects. The same simple explanation - absent much of any concept of selfish or altruistic behavior - probably applies

>Very simply, animals learn to avoid such insects. The same simple explanation - absent much of any concept of selfish or altruistic behavior - probably applies to bees as well, regardless of their colony structure. Once an animal is stung by a bee, it learns to avoid bees, which reduces predatory pressure on all bees (including bee mimic species). In a thread full of Not Even Wrong answers, I would say this is at least the right kind of answer. It stands to reason, I think, that barbed stinger + tear-off of stinger really does serve the purpose of inflicting maximal pain plus pheromone signalling. It's a bit unsatisfying as an answer however, as it would stand to reason that the same can be achieved without necessarily needing to trigger the death of the bee itself. Regarding it being an accident of evolution, I would say I find it implausible that this one is accidental - a barbed stinger is specific and seemingly tailored (in a manner of speaking, not literally) toward a tear-off. With the example of humans having large brains which make childbirth difficult, by contrast, it's easy to see it as an unintended downstream consequence.