Results 21 to 30 of about 1,243,825 (262)

Natural and Engineered Sex Ratio Distortion in Insects

Frontiers in Ecology and Evolution, 2022
Insects have evolved highly diverse genetic sex-determination mechanisms and a relatively balanced male to female sex ratio is generally expected. However, selection may shift the optimal sex ratio while meiotic drive and endosymbiont manipulation can ...
Austin Compton, Austin Compton, Zhijian Tu, Zhijian Tu   +3 more
doaj   +1 more source

CHINCHILLA SEX RATIO [PDF]

Reproduction, 1968
Summary. The proportion of 119 male to 100 female live births in the chinchilla is considerably higher than the values reported for most other mammals. This excess of male births might be connected with the unusually pronounced difference in size of the X- and Y-chromosomes.
openaire   +2 more sources

Haploid selection, sex ratio bias, and transitions between sex-determining systems.

PLoS Biology, 2018
Sex determination is remarkably dynamic; many taxa display shifts in the location of sex-determining loci or the evolution of entirely new sex-determining systems. Predominant theories for why we observe such transitions generally conclude that novel sex-
Michael Francis Scott, Matthew Miles Osmond, Sarah Perin Otto   +2 more
doaj   +1 more source

Modeling and forecasting sex differences in mortality: a sex-ratio approach

Genus, 2018
Female and male life expectancies have converged in most industrialized societies in recent decades. To achieve coherent forecasts between females and males, this convergence needs to be considered when forecasting sex-specific mortality.
Marie-Pier Bergeron-Boucher, Vladimir Canudas-Romo, Marius Pascariu, Rune Lindahl-Jacobsen   +3 more
doaj   +1 more source

Sex roles and sex ratios in animals

Biological Reviews, 2022
ABSTRACTIn species with separate sexes, females and males often differ in their morphology, physiology and behaviour. Such sex‐specific traits are functionally linked to variation in reproductive competition, mate choice and parental care, which have all been linked to sex roles.
Kappeler, Peter M., Benhaiem, Sarah, Fichtel, Claudia, Fromhage, Lutz, Höner, Oliver P., Jennions, Michael D., Kaiser, Sylvia, Krüger, Oliver, Schneider, Jutta M., Tuni, Cristina, van Schaik, Jaap, Goymann, Wolfgang, Benhaiem, Sarah; 3 Department of Ecological Dynamics Leibniz Institute for Zoo and Wildlife Research Alfred‐Kowalke‐Strasse 17 D‐10315 Berlin Germany, Fichtel, Claudia; 1 Behavioral Ecology and Sociobiology Unit, German Primate Center – Leibniz Institute of Primatology Kellnerweg 4 37077 Göttingen Germany, Fromhage, Lutz; 4 Department of Biological and Environmental Science Ambiotica, University of Jyväskylä PO Box 35 40014 Jyväskylä Finland, Höner, Oliver P.; 5 Department of Evolutionary Ecology Leibniz Institute for Zoo and Wildlife Research Alfred‐Kowalke‐Strasse 17 D‐10315 Berlin Germany, Jennions, Michael D.; 6 Division of Ecology & Evolution, Research School of Biology ANU College of Science, The Australian National University RN Robertson Building, 46 Sullivans Creek Road Canberra ACT 2600 Australia, Kaiser, Sylvia; 7 Department of Behavioural Biology University of Münster Badestr. 13 48149 Münster Germany, Krüger, Oliver; 8 Department of Animal Behavior Bielefeld University Morgenbreede 45 33615 Bielefeld Germany, Schneider, Jutta M.; 9 Department of Biology, Institute of Zoology Universität Hamburg Martin‐Luther‐King Platz 3 20146 Hamburg Germany, Tuni, Cristina; 10 Department of Biology II Ludwig Maximilians University of Munich Großhaderner Str 2 82152 Planegg‐Martinsried Germany, van Schaik, Jaap; 11 Applied Zoology and Nature Conservation University of Greifswald Loitzer Str. 26 17489 Greifswald Germany, Goymann, Wolfgang; 12 Department of Behavioural Neurobiology Max Planck Institute for Ornithology Eberhard‐Gwinner‐Str. 6a D‐82319 Seewiesen Germany   +22 more
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Mother's occupation and sex ratio at birth

BMC Public Health, 2010
Background Many women are working outside of the home, occupying a multitude of jobs with varying degrees of responsibilities and levels of psychological stress. We investigated whether different job types in women are associated with child sex at birth,
Amiot Volodymyr, Colijn Grant P, Ruckstuhl Kathreen E, Vinish Erin   +3 more
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Natural Selection and the Sex Ratio [PDF]

Nature, 1960
IN a recent article, Kalmus and Smith1 have attempted to explain why a sex ratio of about one half is selectively advantageous. More recently, Bodmer and Edwards2 have published a paper on the same subject. The two approaches differ in the emphasis placed on different forms of selection. Kalmus and Smith believe that there are two main selective forces
W F, BODMER, A W, EDWARDS
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Air Pollution and Human Sperm Sex Ratio

American Journal of Men's Health, 2018
The present study was designed to address the hypothesis that exposure to specific air pollutants may impact human sperm Y:X chromosome ratio. The study population consisted of 195 men who were attending an infertility clinic for diagnostic purposes and ...
Michał Radwan, Emila Dziewirska, Paweł Radwan, Lucjusz Jakubowski, Wojciech Hanke, Joanna Jurewicz   +5 more
doaj   +1 more source

Observable variations in human sex ratio at birth.

PLoS Computational Biology, 2021
The human sex ratio at birth (SRB), defined as the ratio between the number of newborn boys to the total number of newborns, is typically slightly greater than 1/2 (more boys than girls) and tends to vary across different geographical regions and time ...
Yanan Long, Qi Chen, Henrik Larsson, Andrey Rzhetsky   +3 more
doaj   +1 more source

Leukemia and Exposure to Potential Benzene Sources in Children From the Mexico City Metropolitan Area, 2010–2021: A Geospatial Analysis

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background Leukemia is the most common childhood cancer in Mexico, and acute lymphoblastic leukemia (ALL) is the most frequent subtype. Exposure to high concentrations of benzene has been associated with ALL incidence, particularly in urban areas. This study evaluated the relationship between distance to benzene emission sources and the number
Orlando Rivera Zurita, Norma Candelaria López Santiago, Claudia Maria García Cuellar, Karla Maldonado Silva, Nancy Reynoso Noverón, Leticia Hernández Cadena   +5 more
wiley   +1 more source