Ideal free distribution

This is one way in which animals distribute themselves according to available resources. Twice as many individuals will occupy a habitat patch that contains double the food of another, as long as the animals know what is available elsewhere and are free to choose between the two. You can see the effect for yourself if you go to the seaside: find a friend, buy some chips, stand 10m apart then throw a chip in the air every 10 or 20 seconds, respectively, and count the seagulls that inevitably gather. SB