A question that remains about natural selection is altruism. Why do we, and many animals, do good things for others when the results seem to offer no direct benefit to us? According to research, altruism is instinctive behavior that forms without cultural training in babies [source: CBC]. Other primates also display patterns of altruistic behavior. The explanation for this may lie in the idea of kinship. Blood-related family members share many genes, so helping your relatives could work to ensure some of your genes are passed down. Imagine two families of early people competing for the same food and resources. One of the families has alleles for altruism, helping each other hunt. The other family does not have those alleles, and they hunt separately and don't share food with each other. The first group is more on track to have reproductive success, passing on the altruism alleles.
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