Family dynamics and age-related patterns in marriage probability

Publication date: Available online 9 October 2019Source: Evolution and Human BehaviorAuthor(s): Jenni E. Pettay, Simon N. Chapman, Mirkka Lahdenperä, Virpi LummaaAbstractIn cooperatively breeding species, extended living in natal families after maturity is often associated with limited breeding possibilities and the ability to gain indirect fitness from helping relatives, with family dynamics, such as parental presence and relatedness between family members, playing a key role in determining the timing of own reproduction. How family dynamics affect marriage and the onset of reproduction in humans is complex and less well-understood. While paternal absence can be associated with both earlier puberty and reproductive behaviour, or with delayed reproduction if marriage requires parental resources, in step-parent families, half-siblings could further decrease the benefits from helping and delaying own reproduction compared to families with only full-siblings. Such costs and benefits are likely age-dependent, but have not been addressed in previous studies. Using data from pre-industrial agrarian Finland, we investigated if parental loss and remarriage affected marriage probabilities of their differently-aged sons and daughters. We found that parental composition had divergent effects across adulthood: loss of a parent resulted in a higher probability to marry in early adulthood, whereas parental presence increased later adulthood marriage probability. Whilst the death of either...

Source: Evolution and Human Behavior - October 10, 2019 Category: Psychiatry & Psychology Source Type: research