ABSTRACT
Sexual reproduction involves sexual behavior. Vertebrate species show a number of different mating patterns. Amongst mammals the most common reproductive pattern is known as promiscuity. Sexual differentiation in the embryo depends almost entirely on the presence or absence of testosterone. However, changes at puberty are mostly produced by hormones whose action is specific to the sex of the individual: androgens in males, and estrogens in females. However, such asexual reproduction is extremely rare in vertebrate species. The most straightforward way to do this would be to reproduce alone, thereby passing all of students genes to students offspring. The mating pattern helps to determine the role played by each parent in the reproductive process. Many biologists argue that the prime underlying motivation of all organisms is to maximize the proportion of their own genes in the next generation. Another factor is the biological investment each parent has in the offspring.
