Offspring sex ratios in wild bird populations, and the extent to which they vary from the
equality expected by random genotypic sex determination, have received much recent …

Adult sex ratio (ASR) exhibits immense variation in nature, although neither the causes nor
the implications of this variation are fully understood. According to theory, the ASR is …

Sexual reproduction is a fundamental aspect of life. It is defined by the occurrence of meiosis
and the fusion of two gametes of different sexes or mating types. Sex-determination …

Recent decades have witnessed an explosion of theoretical and empirical studies of sex
allocation, transforming how we understand the allocation of resources to male and female …

Physiological Adaptations for Breeding in Birds is the most current and comprehensive
account of research on avian reproduction. It develops two unique themes: the consideration …

In theory, birds should control the sex ratio of the offspring they produce. In practice, we have
very limited evidence to support this idea because of our difficulty in sexing nestling birds. In …

Abstract Young Seychelles warblers Acrocephalus sechellensis often remain in their natal
territories as helpers. Helpers on low-quality territories (as measured by food availability) …

Birds and mammals are sometimes viewed as black sheep, notorious for their failure to pay
attention to the elegance of adaptive sex ratio theory to the same extent as other animals …

The aim of this review is to consider the potential mechanisms birds may use to manipulate
the sex of their progeny, and the possible role played by maternal hormones. Over the past …

To understand how selection shapes life-history traits, we need information on the manner in
which offspring phenotypes influence fitness. Life-history allocation models typically assume …