Question

Q5.28. Imagine two wolves, a sister and her full-sibling brother, are working together to raise the sister's litter of 10 pups, fathered by an unrelated male. The brother could strike out on his own, in which case he would father 7 pups. However, if he leaves, only 5 pups of his sister's brood will survive. Given that Hamilton's rule says a helping behavior is favored if rB-C>0, what should the brother do to maximize his fitness? (Hint: Click here to review values of r for relationships in diploid species like wolves. ) He should stay and help his sister raise her pups. He should leave to seek a mate and father his own litter. His expected fitness is the same no matter which choice he makes. Hamilton's rule doesn't apply in this scenario. Submit

Answer 1

He should leave to seek a mate and father his own litter.

In case of helping his sister, the B value is 10(pups) and the cost or C value will be 7 offsprings that he will have to let go.

According to Hamilton's rule

rB - C > 0

r value between the brother and his sister's offspring(niece/nephew) is .25 and with his own offspring is .5.

So,

(.25×10) - (.5×7) = -1

-1<0 Hence option b is right.