Sex ratio is an important parameter influencing the demography of wildlife species. Sex ratios are categorized as primary (sex at fertilization), secondary (sex at birth through immaturity), tertiary (sex at adulthood), and quaternary (sex at post-reproductive age). Herein, we examined the secondary(1) (hatchling), secondary(2) (juvenile or subadult), and tertiary (adult) sex ratios of white-winged doves (Zenaida asiatica). Also, because white-winged doves typically hatch two eggs, we also evaluated the secondary sex ratio of co-occurring nestlings. Interestingly, secondary and juvenile sex ratios were significantly male biased, whereas tertiary sex ratios were not biased. Additionally, the ratio of same-sex nestlings was also male biased. The lack of bias at the tertiary level supports Fisher's principle that differential selection for sex ratios of 1:1 exist and lead to more stable populations. Therefore, we conclude that there is some selection mechanism present in this species that selects against males reaching adult status given our findings at the secondary and juvenile sex ratio levels.
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