Against the odds? Nestling sex ratio variation in green-rumped parrotlets
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منابع مشابه
Against the odds? Nestling sex ratio variation in green-rumped parrotlets
We investigated nestling sex ratio variation in the green-rumped parrotlet (Forpus passerinus), a small neotropical parrot breeding in central Venezuela. There are strong theoretical reasons to predict a female-biased sex ratio in this system according to the local resource hypothesis; juvenile males are philopatric and there are high levels of competition between male siblings for access to br...
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Resumen.—Estudiamos el crecimiento en Forpus passerinus, un periquito neotropical pequeño que presenta un período inusualmente largo de presencia de pichones en el nido (– días) y que alimenta a sus pichones con semillas nutricionalmente pobres. Nos preguntamos por qué los pichones crecen tan lentamente a pesar de que la depredación de los nidos es su principal factor de mortalidad. Examina...
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Within the area of sex allocation, one of the topics that has attracted a lot of attention is the sex ratio problem. Fisher (1930) proposed that equal numbers of males and females have been promoted by natural selection and it has an adaptive significance. But the empirical success of Fisher's theory remains doubtful because a sex ratio of 0.50 is also expected from the chromosomal mechanism of...
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ژورنال
عنوان ژورنال: Behavioral Ecology
سال: 2004
ISSN: 1465-7279
DOI: 10.1093/beheco/arh052