Results 11 to 20 of about 1,336,652 (309)
Widespread sex ratio polymorphism in Caenorhabditis nematodes
Royal Society Open Science, 2023 Although equal sex ratio is ubiquitous and represents an equilibrium in evolutionary theory, biased sex ratios are predicted for certain local conditions. Cases of sex ratio bias have been mostly reported for single species, but little is known about its
Yun Huang +7 more
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European Journal of Human Genetics, 2004 Two recent papers suggest distorted sex and transmission ratios associated with BRCA1 mutations. If real, these would provide novel insights into the normal biological function of this gene and have implications for genetic epidemiologic methods used to estimate penetrance.
Jeffery P, Struewing +4 more
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Economic stress affects the human sex ratio: A retest of the Trivers–Willard hypothesis in Poland
Anthropological Review, 2023 This paper contributes to the verification of the Trivers–Willard hypothesis (TWH). Based on the TWH, observed sex (male-to-female) ratio at birth in a population is presumed to decline when parents experience economic stress.
Artur Mikulec +2 more
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On the optimal sex ratio. [PDF]
Proceedings of the National Academy of Sciences, 1983 The equilibrium structures for various multiallele sex-determining genetic models of panmictic populations with sex expression depending on the genotypes of either the zygote or a parent are described. Even-sex-ratio equilibrium surfaces can exist apart from equilibrium points having coincident male and female allelic frequency sets.
Karlin, Samuel, Lessard, Sabin
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Determinants of child sex ratio in West and South Districts of Tripura, India
Indian Journal of Public Health, 2017 Background: Indian census 2011 has detected declined child sex ratio in the West and South districts of Tripura State. Objectives: To find out the sex ratio at birth and to identify the factors affecting child sex ratio in west and south districts of ...
Himadri Bhattacharjya, Subrata Baidya
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Human sex ratio at amniocentesis and at birth in Taiwan
Taiwanese Journal of Obstetrics & Gynecology, 2012 Objectives: An increase in the proportion of male-to-female live births has raised concerns in Taiwan. Disclosure of fetal sex during prenatal screening is not allowed by the Taiwan government.
I-Wen Lee +3 more
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The quantitative genetic basis of sex ratio variation in Nasonia vitripennis : a QTL study [PDF]
, 2010 Our understanding of how natural selection should shape sex allocation is perhaps more developed than for any other trait. However, this understanding is not matched by our knowledge of the genetic basis of sex allocation.
Shuker, DM +20 more
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Inbreeding and selection on sex ratio in the bark beetle Xylosandrus germanus [PDF]
, 2011 Background: Local Mate Competition (LMC) theory predicts a female should produce a more female-biased sex ratio if her sons compete with each other for mates.
Keller, Laurent +19 more
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Climate influences fledgling sex ratio and sex-specific dispersal in a seabird. [PDF]
PLoS ONE, 2013 Climate influences the dynamics of natural populations by direct effects over habitat quality but also modulating the phenotypic responses of organisms' life-history traits. These responses may be different in males and females, particularly in dimorphic
Alvaro Barros +2 more
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Reproduction, 1974 Sex ratios have been the subject of numerous investigations, particularly in studies with humans. In general, however, the literature relating to sex ratio in sheep is limited (Chapman & Lush, 1932; Henning, 1939; Rasmussen, 1940; Karam, 1957). Population studies have generally been based on an expected sex ratio of 0·5, and any ...
K M, Napier, P D, Mullaney
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