Kin selection

Kin selection is simply changes in gene frequencies across generations that are driven in part by interactions between related individuals, and it is also known as the theory of social evolution. Many cases of evolution can be studied by examining how someones relatives can influence another persons fitness. You can see many examples of this in animals and in humans. Eusociality (true sociality) is used to describe social systems with three characteristics: an overlap in generations between parents and their offspring, cooperative child care, specialized heredity of non-reproductive individuals. A great example of kin selected traits can be seen in monkey communities. Data shows that maternal kin, kin related to by mothers, behaved more preferentially towards each other. However, once kin was beyond half-siblings or further relatives, this dropped significantly. Alarm calls in ground squirrels is another example. While they may alert others of the same species of danger, they draw attention to the caller and expose it to increased risk of predation. It has been observed that calls occurred most frequently when the caller had relatives nearby. This is a fascinating example because it is as if they are looking out for their family members. A similar example can be seen in the courtship behavior of the wild turkey.  A subordinate turkey may help his dominant brother put on an impressive team display that is only of direct benefit to the dominant member. Let me give you a question a think about. If your mother, sister, brother, father, even grandfather, what have you, was in need of something, for this example we will say help moving from an old home to a brand new home, but oh darn on this same weekend your best friend is having their birthday party! Which would you choose? Me personally, I would choose helping my family member. Because (as bad as it sounds) family is more important. Studies have been done on this, and the majority of people will help a kin relative opposed to their non kin friend. Studies have demonstrated that relatedness is often important for human altruism (unselfish regard for or devotion to the welfare of others) in that humans are inclined to behave more altruistically toward kin than toward unrelated individuals. Many people choose to live near relatives, exchange sizable gifts with relatives, and favor relatives in wills in proportion to their relatedness. Chapter 12 was an interesting chapter to read because my family is very important to me. I was raised in a southern family, and I know that no matter what challenges I go through in life, my family will always be there for me. I knew this occurred in humans off course, but it is assuring and compelling that it also occurs in animals.
This video explains kin selection and gives many good examples of altruism:

Also, check out these links for more information on kin selection:

http://link.springer.com/article/10.1007%2FBF01065540?LI=true

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/K/KinSelection.html