Women can give birth and also are naturally necessary for child rearing although many varying circumstances dictate actual living situations and conditions. Genetically speaking this means women are more necessary than men on survival terms for life itself. Men only donates the other half of a complete set of chromosomes in order to make another human. After that job is done genetics say the male is less necessary than the woman in terms of genetic survival. Many species such as in the insect kingdom the males die off after reproduction.