Pál Koudela: Fertility and Evolution. Changes in Reproductional Strategies in the Information Age

Article

The first demographic transition can be interpreted as a change in reproduction strategies. Under bad conditions the safest way for humans to ensure their offspring is to increase their number; under good conditions it is easier to have fewer offspring with more parental investment. The further decreasing of fertility in the second demographic transition can be explained by the reduction of the size of the primary group. In the first and longest period of human evolution, the separated, face-to-face groups were typical. In such a competitive situation the pressure for under selection loyalty became a very adaptive feature. From the evolving societies original groups eroded. Tribes became clans, clans became extended families and later nuclear families. Now the final group size is the one-person group. People help their group to be successful when they have a career, and they give up their personal interests when not having children.