Balls of fire – group defense against predators

Came across a very interesting report in the Science News – Honeybees swarm a predatory Killer Wasp and collectively raise their body temperatures to a point where the Wasp gets killed. Extremely interesting. In general, the smaller the size the harder it is to ward off bigger predators.  Some insects, fishes etc. have evolved what are known as aposematic displays to warn predators.  The wikipedia entry on aposematism has some excellent links. Social Caterpillars entry in the Wikipedia has some interesting material on group defense:

It is generally thought that aposematic coloration is most effective in deterring predators when insects group together. Indeed, the most common mode of active defense among social caterpillars is aposematic display, often combined with synchronous body rearing, flicking, and “en masse” regurgitation of toxic or unpalatable chemicals. Studies indicate that the spread of alarm through colonies of social caterpillars is mediated largely by tactile and, possibly, visual cues. Caterpillars can detect the airborne sounds generated by the beating wings of flying wasps and flies and respond with rapidly jerking movements. Vibrational signals set up by the agitated caterpillars and propagated by the communal web would appear the most likely means of alerting the colony to danger.