Abstract
(1) The principal purpose of this paper is to show that in birds a great deal of well-documented evidence exists proving the occurrence of strongly uneven sex ratios. (2) The sex ratio may be high or low, favoring the male or the female sex. (3) The evidence points to the existence of this unbalanced condition already in the primary sex ratio, although physiological and environmental factors may modify it during prenatal and postnatal life. (4) In nearly all well-studied cases unequal sex ratios have been found to be correlated with peculiarities in the life history of the birds. (5) The study of the cytology and genetics of sex determination in birds is a promising and practically untouched field.
Keywords
Sex ratioBiologyLife historyZoologyDemographyOperational sex ratioEcologyPopulation
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Publication Info
- Year
- 1939
- Type
- article
- Volume
- 73
- Issue
- 745
- Pages
- 156-179
- Citations
- 140
- Access
- Closed
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Cite This
Ernst Mayr
(1939).
The Sex Ratio in Wild Birds.
The American Naturalist
, 73
(745)
, 156-179.
https://doi.org/10.1086/280824
Identifiers
- DOI
- 10.1086/280824