Can Birds Influence the Gender of their Young?

Petr J.

A peculiar phenomenon influencing the gender of bird young consists of processes taking place at several levels (such as growth of follicles in the ovary, during fertilization and during development in the oviduct), which can be influenced by a wide range of internal and external factors (including stress). A significant shift in gender in descendants has been found in many bird species (e.g. Acrocephalus seychellensis).

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