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Updated: Aug 3, 2026

Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Social structure and U.S. inter-state fertility differentials in 1900
Abstract:
This paper investigates the importance of agricultural land shortages versus modernization of the society in influencing inter-state differentials in fertility in 1900, when the United States was in mid-transition. Urbanization and manufacturing characteristics of states were the strongest correlates of variations in the index of total fertility because urban-industrialism depressed both the probability of marriage and marital fertility. Other modern characteristics of American states were also important in understanding variations in marital fertility. Low labor force employment of children and farm mechanization, integrally related characteristics, seemed to depress levels of marital fertility in many parts of the United States, independent of the urban-industrial system. Agricultural land opportunity had little overall effect on marital fertility; however, it was quite important in understanding variations in patterns of marriage.
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