Final answer:
Kin selection refers to the preferential survival and reproduction of individuals who share genes with each other. The adoption of a kitten by female red squirrels can be considered an example of kin selection as it benefits the shared genetic lineage.
Step-by-step explanation:
Kin selection is a concept in biology that refers to the preferential survival and reproduction of individuals who share genes with each other, even if it means sacrificing their own reproductive success. In the case of female red squirrels adopting a kitten, this behavior can be considered an example of kin selection. By adopting and caring for a kitten, the female squirrel increases the survival chances of the kitten, which shares some of her genes. This behavior benefits the shared genetic lineage and increases the overall reproductive success of the genes carried by both the female squirrel and the kitten.