Recent studies suggest that ants may be constantly sending a chemical signal indicating that they are dead -- even while they are still alive! According to Dong-Hwan Choe of the University of California, Riverside, ants begin producing the compound in question from the beginning of their adult lives, and must rely on further chemical measures to avoid colony-wide confusion. Apparently, to keep their fellow hivemates from hauling them to the graveyard, living ants constantly produce another set of chemicals that mark them as alive and well. Upon death, these "alive" signals cease to be produced and dissipate quickly, leaving only the long-lasting "dead" chemical on the body and alerting other ants that cleanup is necessary.

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