When trekking through a forest in French Guiana to study termites, a group of biologists noticed unique spots of blue on the backs of the insects in one nest. Curious, one scientist reached down to pick up one of these termites with a pair of forceps. It exploded. The blue spots, the team discovered, contain explosive crystals, and they’re found only on the backs of the oldest termites in the colony. The aged termites carry out suicide missions on behalf of their nest mates.