Secondary Sex Ratio in Eurasian Eagle-Owls: Early-breeding Females Produce More Daughters
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چکیده
منابع مشابه
Humans at tropical latitudes produce more females.
Skews in the human sex ratio at birth have captivated scientists for over a century. The accepted average human natal sex ratio is slightly male biased, at 106 males per 100 females or 51.5 per cent males. Studies conducted on a localized scale show that sex ratios deviate from this average in response to a staggering number of social, economical and physiological variables. However, these patt...
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Sex allocation theory predicts that parents bias the offspring sex ratio strategically. In avian species, the offspring sex ratio can be biased at multiple growth stages, although the mechanisms are not well known. It is crucial to reveal a cause and timing of biased offspring sex ratio. We investigated (i) offspring sex ratio at multiple growth stages, from laying to fledging; and (ii) the sta...
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ZIMMER, E. A., AND K. J. NEWTON. 1982. A simple method for the isolation of high molecular weight DNA from individual maize seedlings and tissues, pp, 165-168. In W. F. Sheridan (ed.), Maize for Biological Research. Plant Molecular Biology Assoc., Charlottesville, VA. ZIMMER, E. A., E. R. lUPE,AND V. E. WALBOT. 1988. Ribosomal gene structure, variation and inheritance in maize and its ancestors...
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A review of published reports showed that the sex ratio (proportion of boys) was low among infants conceived after ovulation had been induced. The difference between the observed sex ratio and an expected one of 0 . 514 was highly significant. These findings suggest that maternal gonadotrophin concentrations at the time of conception directly affect the sex of the zygote.
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BACKGROUND Lunar cycles seem to affect many of the rhythms, temporal patterns and behaviors of living things on Earth. Ambient light is known to affect visual communication in animals, with the conspicuousness of visual signals being largely determined by the light available for reflection by the sender. Although most previous studies in this context have focused on diurnal light, moonlight sho...
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ژورنال
عنوان ژورنال: Journal of Raptor Research
سال: 2010
ISSN: 0892-1016
DOI: 10.3356/jrr-09-08.1