The main function of sex in nature is reproduction that it, producing babies and carrying on the species, whether the species be birds, b ees, rabbits, hamsters, hippopotamuses, gorillas, or human beings. Nothing in nature could be more important, and that is why sex is so attractive and the drive for it so urgent. However, there are important differences between sex in animals and sex in human beings.
One difference is this; in most animals, copulation or mating usually take place only when the feamle is in heat- that is, as she is ovulating and when copulation will produce pregnancy. When she is in heat, she gives forth a certain scent or other sign which tells the male she is ready to copulate. The male then becomes sexually aroused (he 'ruts' or becomes 'rutty') and the mating takes place. At no other time is the female willing to copulate, and usually only at that time is the male responsive.
Thus, the main result of copulation in animals is reproduction. Of course, animals do not 'know' this. They copulate because they feel an urge to do so. In human females, on the other hand, there is no such thing as heat. Most women usually do not even know when they have ovulated and have an egg that is ready to be fertilized.
They do feel a greater desire for intercourse at some times than at others, but not necessarily at the time when they are most likely to conceive. Women do not give forth any special scent; their bodies do not advertise their readiness, as do animal bodies. Further, the human male is more or less always ready for sexual activity.
There is no definite season when he is 'rutty'. Thus, human sexual desire has relatively little relationship to whether or not a baby is likely to be produced at a given time. Most sexual intercourse between human beings takes place because of the desire, pleasure, joy, and love that are a part of it, rather than because of the need to produce children.