Sex ratios at birth vary with environmental harshness but not maternal condition
نویسندگان
چکیده
منابع مشابه
Maternal Condition Does Not Influence Birth Sex Ratios in Anubis Baboons (Papio anubis)
Trivers and Willard predicted that when parental condition has differential effects on the fitness of male and female offspring, parents who are in good condition will bias investment toward the sex that benefits most from additional investment. Efforts to test predictions derived from Trivers and Willard's model have had mixed results, perhaps because most studies have relied on proxy measures...
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Split-sex-ratio theory assumes that conflict over whether to produce predominately males or female reproductives (gynes) is won by the workers in haplodiploid insect societies and the outcome is determined by colony kin structure. Tests of the theory have the potential to provide support for kin-selection theory and evidence of social conflict. We use natural variation in kinship among polygyno...
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BACKGROUND Skewed male:female ratios at birth have been observed among certain immigrant groups. Data on abortion practices that might help to explain these findings are lacking. METHODS We examined 1 220 933 births to women with up to 3 consecutive singleton live births between 1993 and 2012 in Ontario. Records of live births, and induced and spontaneous abortions were linked to Canadian imm...
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Fertility transition in China deviates from the classical model in two ways. First, fertility decline in China was extraordinarily rapid with low level of socio-economic development; second, the change has been from a high fertility regime to a low and sex-selective pattern of childbearing. The two processes are directly the result from China’s family planning program, which is the most stringe...
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We test two models of adaptive adjustment of birth sex ratios that are expected to apply to Cercopithecine primate species. It has been predicted that when maternal investment differentially influences the reproductive success of male and female offspring, females in good condition will bias investment in favour of the sex that gains the greatest fitness returns from additional investment. This...
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ژورنال
عنوان ژورنال: Scientific Reports
سال: 2019
ISSN: 2045-2322
DOI: 10.1038/s41598-019-45316-7