Universal "Death Stench" Repels Bugs of All Types

Hugh Pickens writes "Wired reports that scientists have discovered that insects from cockroaches to caterpillars all emit the same stinky blend of fatty acids when they die and that the death mix may represent a universal, ancient warning signal to avoid their dead or injured. 'Recognizing and avoiding the dead could reduce the chances of catching the disease,' says Biologist David Rollo of McMaster University 'or allow you to get away with just enough exposure to activate your immunity.' Researchers isolated unsaturated fatty acids containing oleic and linoleic acids from the corpses of dead cockroaches and found that their concoction repelled not just cockroaches, but ants and caterpillars. 'It was amazing to find that the cockroaches avoided places treated with these extracts like the plague,' says Rollo. Even crustaceans like woodlice and pillbugs, which diverged from insects 400 million years ago, were repelled leading scientists to think the death mix represents a universal warning signal. Scientists hope the right concoction of death smells might protect crops. Thankfully, human noses can't detect the fatty acid extracts. 'I've tried smelling papers treated with them and don't smell anything strong and certainly not repellent,' writes Rollo in an e-mail. 'Not like the rotting of corpses that occurs later and is detectable from great distances.'"

Comments

How does this play into natural selection?

[Chameleon Man]

Am I missing something, or does the evolutionary process in developing this not line up? I was always under the impression that individual species were in constant competition with each other (with the exception of living in a society where symbiotic relationships occur). Accounting for natural selection, how can the "death stage" be improved generation by generation when the species that develops this ability is...well...dead?

Re:This is nonsense

[MBGMorden]

It also seems to not jive with the currently understood mechanics of evolution. DETECTING such a stench would lead to a survival advantage, but actually emitting it is something done after death - so there is no natural selection at work to lead to the unification of a "death scent" to evolve towards.