The influence of wealth class in modifying selection for female life-history traits was studied using demographic data collected from Finnish population registers of the pre-industrial era. The Lutheran Church has kept census, birth/baptism, marriage and death/burial registers of each parish in the country since the 17th century, covering the whole population of Finland from 1749 onwards. We used demographic data collected from five Finnish parishes (Hiittinen, Kustavi, Pulkkila, Rymättylä, and Ikaalinen) of the 18–19th century [37] –[38] . We recorded complete life histories for mothers and for one generation of their all reproductive female offspring (n = 704). During the study period these populations depended on farming and fishing for their livelihood [16] , [27] and experienced high mortality and fertility due to the lack of modern medical care and contraceptive methods.
We classified individuals according to their socio-economic status. Because we had no direct knowledge of the actual wealth of the families, such as taxes paid or farm size, and since women at our study period rarely had an occupation of their own, we used a husband's occupation as a reference to wealth and social status of women. We divided women to three wealth classes; rich, middle-class, and poor. The Rich class included noblemen, priests and free farmers, the Middle-class included mainly tenant farmers and craftsmen, while the Poor included servants and dependent lodgers. This categorization was based on the historical studies of Finnish populations [37] –[38] . Inheritance of wealth class for females was moderately high: in these data, 54% of the Rich women's daughters had the same wealth class as their mothers. For the Middle-class and the Poor, the inheritance of wealth class was 62% and 39%, respectively.
We studied the following female life-history traits:
We classified individuals according to their socio-economic status. Because we had no direct knowledge of the actual wealth of the families, such as taxes paid or farm size, and since women at our study period rarely had an occupation of their own, we used a husband's occupation as a reference to wealth and social status of women. We divided women to three wealth classes; rich, middle-class, and poor. The Rich class included noblemen, priests and free farmers, the Middle-class included mainly tenant farmers and craftsmen, while the Poor included servants and dependent lodgers. This categorization was based on the historical studies of Finnish populations [37] –[38] . Inheritance of wealth class for females was moderately high: in these data, 54% of the Rich women's daughters had the same wealth class as their mothers. For the Middle-class and the Poor, the inheritance of wealth class was 62% and 39%, respectively.
We studied the following female life-history traits:
Age-specific probability of survival according to the wealth class of the parents
Probability of marriage by the wealth class of the parents for those women who survived to age of 20 years
Age at first reproduction (AFR), including illegitimate births
Time in months from marriage date to birth of the first child excluding women who had their first child before marriage
Fecundity (FEC), the number of children born to a woman during her lifespan
Offspring survival (%SURV), the proportion of children born that survived to age of 15 years
Age at last reproduction (ALR)
Lifetime reproductive success (LRS), the number of children who survived to age of 15
Longevity (LONG), age at death
Number of grandchildren born
Free full text: Click here
