Parental investment is defined as “any investment made by the parent in an individual offspring that increases the offsprings chance of survival.” There are differences in how much each gender invests in their offspring, according to evolutionary theories.
Female investment in a child is usually greater. This is because female’s can have limited offspring, whereas men can have potentially an unlimited offspring, as well as this, females also make a greater pre and post natal commitment. The female must carry and nourish the child for 9 months, and then continue breastfeeding and care for the baby once it is born, as the child cannot get this care from the male, the male’s investment is much less, as the male can “opt out” where the mother cannot. The investment made by mothers is also great, as human babies are more dependant and require more care, as they are born less developed than other species.
A reason why male investment is less of that than females is because males are always at risk of cuckoldry – investing resources in another man’s child – where females are always certain the child is theirs. Therefore the males invest less in the child, to reduce the risk of cuckoldry and therefore reduce potential resource wasting. Additionally, the risk of cuckoldry means there is more concern from the males over the sexual fidelity of mates, so as their investment is well spent. Conversely, a women’s concern is more prominently over emotional fidelity, as they want to increase the male investment in the child, so the child has good resources, which increases the chance of offspring survival.
However there are some problems with this explanation of sex differences. One key flaw is that is offers no explanation for why some women desert their children after birth or in some cases commit infanticide, these two situations demonstrate that the mother is not always keen to