Results 11 to 20 of about 7,415,942 (348)
Mate limitation and sex ratio evolution [PDF]
Royal Society Open Science, 2018 Sex ratio evolution has been one of the most successful areas of evolutionary theory. Pioneered by Düsing and Fisher under panmixia, and later extended by Hamilton to cover local mate competition (LMC), these models often assume, either implicitly or ...
Jussi Lehtonen, Lisa E. Schwanz
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Social Sciences, 2023 Researchers have long puzzled over suicidal behavior. In this paper, we posit that when people are unable to attract mates given unfavorable sex ratios, suicide rates increase. Sex ratio, the proportion of males in a population, is linked to a variety of
Kristin Snopkowski, Hallie Turner
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Comparison of the effect of sex ratio on the Partridge Alectoris chukar performance, which was bred under standard conditions in Nineveh [PDF]
مجلة جامعة كركوك للعلوم الزراعية, 2021 The research was carried out in the Livestock Research Division / Nineveh Research Department to study the effect of four different treatments of Sex ratio male: female (1: 1, 1: 2, 1: 3 and 1: 4), using 477 birds at production age, for 10 weeks on the ...
Firas Ibrahim +2 more
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Parasite stress predicts offspring sex ratio. [PDF]
PLoS ONE, 2012 In this study, I predict that the global variation of offspring sex ratio might be influenced in part by the level of parasite stress. From an energetic standpoint, higher gestational costs of producing a male offspring could decrease male births in a ...
Madhukar Shivajirao Dama
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Recent sex ratio at birth in China
BMJ Global Health, 2021 Background China’s sex ratio at birth (SRB) has declined in the past decade but still exceeds the normal level. This study seeks to depict the SRB trend in the past two decades.Methods We depicted the SRB trend, including SRB by birth order, children ...
Quanbao Jiang, Cuiling Zhang
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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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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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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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Proceedings of the National Academy of Sciences of the United States of America, 2019 Significance This study provides information on sex ratio at birth (SRB) reference levels and SRB imbalance. Using a comprehensive database and a Bayesian estimation model, we estimate that SRB reference levels are significantly different from the ...
Fengqing Chao +3 more
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