David Attenborough's Life in the Undergrowth (which I've mentioned at least twice before) has a parasite story that is so amazing that it's hard to believe it is true. The six-minute, third-two second segment is on-line at YouTube and should be embedded below.
The key to the success of the caterpillar and the wasp is chemical signaling — the caterpillar smelling like an ant larva and wasp causing ants to turn on their nest-mates. Humans can also sometimes exploit these chemicals. A 2006 story in the San Francisco Chronicle tells of research on the chemical signals used by Argentine ants (the bane of many a Californian), with one of the goals being discovery of a chemical that will cause the ants to attack each other (perhaps by making them smell like invaders). Another interesting story about ants and chemicals can be found in one of Radiolab's short pieces, a conversation between host Robert Krulwich and legendary entomologist E.O. Wilson. Wilson tells of some of his ant experiments, including a rather devious one where he dabbed ants with the chemical given off by a dead ant. When a worker detects the 'dead ant scent,' it carries the corpse out of the nest to the trash heap. And so, the live ant got the same treatment and was carried out of the nest several times until it was able to clean itself.
Random link from the archive: Recipe - Roman style carrots
Technorati tags: Insects : Ants : Nature