Question

In vertebrate societies, what are the costs to an individual who makes an alarm call? Based on research in ground squirrels, which individuals are most likely to make alarm calls, and what benefits do they receive by doing so?

Answer 1

Kin selection is an evolutionary strategy that favours the reproductive success in an organism'srelatives, even at the cost of it's own survival and reproduction.

According to Hamilton's rule an individual show altruistic behavior only when rB>C

r=the genetic relatedness of the recipient to the actor.

B=the additional reproductive benefit gained by the recipient of the altruistic act,

C=the reproductive cost to the individual performing the act.

Ground squirrels were live in dense colonies. The females mate with one or more males and she raises her offsprings inside the burrow.

As per Hamilton's rule they show self sacrificing behavior. When they spot a predator they produce an alarm call so that the other females can pop down their burrows to safety and can escape from the predator. But the squirrel that produce alarm call easily catches predators attention and likely to be killed by the predator.

Females, who have nearby relatives, give alarm calls more often. Males who have no near kin call less often.  females with only their mother or sister in the area are more likely to call than females with no relatives.