Lecture 9: social behaviour of female lions, territory defence: territory defence can be quite vicious, they defend feeding territories, against other prides of lions. And they need large areas in order to feed the offsprings in their pride: they had models of lions, and produced playbacks of roars. Lions are good at estimating of how many roars there are at the same, so they can estimated the number of individuals coming in as a threat. there is a variation in defence behaviour. there are leaders: they approach playback first and more rapidly. Laggards: lag enough for the leaders to get attacked, and the laggards avoid being attacked. I t was always the leader that was injured : leading is a risky behaviour. where does lagging come from: altruism : groups of related individuals. But we don"t see typical relationship we see with altruism. I t is not the case that anyone is defecting.