Sexual size dimorphism and food requirements of nestling birds

摘要: The food requirements of dependent sons and daughters have important implications for evolution the sex ratio, according to current allocation theory. We studied nestling American kestrels (Falco sparverius), a moderately size-dimorphic falcon, by hand-feeding 61 birds from hatching fledging. Daughters, larger gender, consumed 6.99% more than did sons. Sons not higher energy expenditure effort during sibling competition did, so parents must supply satisfy daughters' needs sons'. A review all related studies shows strong positive association between degree sexual size dimorphism gender difference in requirements.