> So what we found that instead of this being some collective, cooperative
> behaviour, what we have in fact is a forced march. Every cricket is
> trying to eat the one ahead and prevent itself from being eaten from
> behind. We found that they were very aggressive with each other,
> attacking an immobile insect within 17 seconds and really jumping on it
> and biting it. So one may then ask questions; why, if it's so dangerous
> to be in a swarm, why don't they leave? But another colleague at the
> University of Sydney, Greg Sword, using tiny little radio transmitters
> on these crickets found that it's even more dangerous to leave the group
> because they get eaten by predators. So really they're making the best
> of a rather bad situation.
Kind of explains radical melees with the police during militant protests. The swarm of the crowd can be very effective in protecting the protesters from the predators (the cops). The predators can beat on and arrest a few members of the swarm, but you can literally participate in many of these "swarms" without ever being affected by the predators.
The members of the swarm save their cannibalistic behavior for meetings and Internet discussion lists. ;-)
Chuck