jennifer mills, motivation is more likely to competing for mating opportunities that we have the hormonescoordinate the availability of the eggs and sperm the physical traits we need to have that nurturing in the competition and in the brain to motivate the individuals to use those traits, negative muscles or lactation if you don't have motivation to use those muscles or to use those breast to figure offspring into the home runs to all of these different things by affecting how the wasted energy is been a body and muscle or fat egg production right-center and then i'll start for the males and you throw so the females don't actually need their ovaries to be n producing estrogen to devep their t reproductive anatomy nor to do anything special to the brain but the males have very high, testes and utero humans and another animal, very high levels of testosterone but masculinized the reproductive structures essentially grow the and the associated kind of internal plumbing is setn a new front during the same. , and also acts in the brain to masculinized certain structures. for instance young ma