This refers to the investment that a parent makes to raise an offspring. While parental investment can lower the chances of survival of the parent, it helps in the reproductive success of a species by facilitating the passing of its genes to the next generation. The amount of parental investment can differ between the male and female of a species and this has been used to explain various mating preferences, most notably by American biologist Robert Trivers. The idea of parental investment was first proposed by the British biologist Ronald Fisher in his 1930 book The Genetical Theory of Natural Selection.
