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Updated: May 6, 2026

A Method to Test the Effect of Environmental Cues on Mating Behavior in Drosophila melanogaster
Published on: July 17, 2017
Relationships between the human sex ratio and the woman's microenvironment : Four tests
1Social Service Division, El Paso Community College, 79998, El Paso, TX.
Abstract:
Independent samples of women were surveyed to test Trivers and Willard's hypothesis that the mother's condition and her ability to invest in her offspring affect the (secondary) sex ratio of her offspring. Patterns of sex ratios (number of males per 100 females) were analyzed in conjunction with four attributes of a mother's microenvironment: level of health in her community, family structure, relative access to resources, and her birthing history. The results inferentially support the hypothesis that the microenvironment of the woman would act to bias the sex ratio of her offspring. These specific data lend support to Trivers and Willard's general hypothesis.
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