title: Sex-linked strategies of human reproductive behavior.
abstract: We present data on fertility characteristics in the Venezuelan population for each sex separately, allowing a detailed comparative analysis of the variance in fertility between males and females. We show that the fertility distribution for both sexes is discontinuous, that the average female has a larger number of offspring per individual than the average male, and that highly fertile males outnumber highly fertile females so that the total number of offspring produced by males and females is balanced. Results indicate that a few males are responsible for a relative higher fertility of the average female and that interactions between polyandric females with monogamic and polygynic males are common. Among the Yanomami, a relatively unacculturated hunter-gatherer-horticulturist tribe, similar differences in fertility distribution of both sexes are apparent. The data suggest that human populations contain statistically distinct subpopulations, with different reproductive strategies, suggesting the existence of complex interactions among human populations which are not evident from the study of individuals or groups.
authors.affiliation: Departamento de Biologia de Organismos, Universidad Simon Bolivar, Caracas, Venezuela.
authors.forename: K
authors.initials: K
authors.lastname: Jaffe
authors.forename: D
authors.initials: D
authors.lastname: Urribarri
authors.forename: G C
authors.initials: GC
authors.lastname: Chacon
authors.forename: G
authors.initials: G
authors.lastname: Diaz
authors.forename: A
authors.initials: A
authors.lastname: Torres
authors.forename: G
authors.initials: G
authors.lastname: Herzog
mesh_terms: D000293:Adolescent; D000328:Adult; D003625:Data Collection; D005260:Female; D005298:Fertility; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D008297:Male; D008875:Middle Aged; D011157:Population Dynamics; D017678:Sex Distribution; D014687:Venezuela