Human animals have a simple, direct system: copulation and sperm delivery may lead to fertilization of an egg, if the timing is right. Once a sperm joins an egg, the resulting zygote gets implanted on ...

A new article in Ecological and Evolutionary Physiology examines how the immune system and reproduction interact in female mammals, especially during pregnancy, from mating to birth. Lauren E.

An underlying principle of female reproductive biology appears to have been overturned by a report from researchers at Massachusetts General Hospital (MGH). In an article in the March 11, 2004 issue ...

Parents should bias sex allocation toward offspring of the sex most likely to provide higher fitness returns. Trivers and Willard proposed that for polygynous mammals, females should adjust sex-ratio ...