In fact, social monogamy is extremely common in birds and somewhat common in mammals, while sexual monogamy is vanishingly ...

If bird becomes male, Wolffian ducts develop into vas deferens or sperm duct and Mullerian ducts atrophy. The reverse occurs in the developing female. However, only the left Mullerian duct (and ...

As you begin to see nests full of baby chicks and fledgling birds hopping around in your backyard, you may wonder: how do ...

The natural world is replete with hermaphrodites, animals that may outwardly appear male or female but have the reproductive organs ... has been documented in birds, crustaceans—and butterflies.

A white-breasted, female frigatebird observes the courtship display of her male partner. The two are part of a colony on ... Conservation of Nature ranks the bird “least concern,” but invasive ...

If bird becomes male, Wolffian ducts develop into vas deferens or sperm duct and Mullerian ducts atrophy. The reverse occurs in the developing female. However, only the left Mullerian duct (and ...