This is the 2007 version. Click here for the 2017 chapter 16 table of contents.

Sex and Aggression

Sex itself can be very aggressive. In many different mammalian species sexual encounters look like fights, sometimes accompanied by thrashing about, loud noises, and (in cats) mock biting, scratching, then a final act of pushing away that looks distinctly unfriendly. However, even after such displays, male and female cats such as lions remain in each other's proximity for multiple matings, so evidently the act of reproduction is not aversive to them.

How do hormones link sex and aggression in males?

Perhaps one reason sex and aggression alternate so easily is that they are related by evolution and biology. In Chapter 8 (p.701) we discussed how winning a fight increases levels of the sex hormone, testosterone, in primate species. Therefore the male winner of a fight benefits in reproductive success: he has more access to females, and he has higher levels of male hormone that fosters greater degrees of sexual activity as well as aggression.

What are some patterns of sexual behavior among the bonobos?

However, not all primates are aggressive. In at least one species, aggression takes second place to sex. The "pygmy chimpanzee" or bonobo (bo-NO-bo) is the human's closest relative among primates. Among bonobos, sex is frequent, bisexual, and promiscuous. Almost anything exciting (such as anticipated food) causes Bonobos to initiate sexual contacts with one another. This makes bonobos unlike other types of chimpanzees, who fight more and have sex less.

Bonobos often appear to divert aggressive impulses into sexual behavior, and they often initiate a sexual encounter to reconcile with each other after an aggressive display. A female bonobo might walk up to a dominant male who is hoarding food, display sexually, participate in intercourse for up to 15 seconds, take some food, and walk away. Female genital-to-genital contacts are equally common. It looks like a hug and typically lasts only a few seconds. Among bonobos, sex is used as a pacifier, a form of reassurance, and a sign of friendship.

How are sex and aggression sometimes related in human behavior?

Among humans, aggression is sometimes diverted into sexual behavior. This is a well-known pattern in certain dysfunctional (abnormal or poorly functioning) relationships. Fighting or arguments are part of a routine that ends in "kissing and making up." That seems to be the case in the following relationship.

In our study of love, I realized that masochism and sadism were definitely involved in the relationship of two friends of mine. Jerry and Kim have been dating for about two years. It is evident that they truly care about each other, but they are continuously arguing and seem to be constantly plagued with some type of problem. Aside from all of their various problems, there is one pattern that I have noticed frequently.

They always start out arguing at first. Jerry has a quick temper and Kim knows it, but she will repeatedly slap him, usually just on the arm, or pull on him to get him to come along. He will tell her to quit, as he becomes more and more annoyed, but she continues to aggravate him. Finally, he hits her. Usually he hits her hard. He instantly realizes that he hit her harder than he intended, and he is truly sorry. She begins crying, and he floods her with affection. He tells her how sorry he is and how much he loves her, and eventually things settle back down to normal.

It is evident that Kim brings this upon herself. She considers the pain worth it, to get the affection she otherwise does not receive. She often uses this technique when Jerry has been drinking, because it is quite easy to pull it off then. She also knows that Jerry is very jealous and she will use that to make him become aggravated enough to hit her. I have seen her showing her bruises to people, informing them that Jerry hit her. Of course, she does not tell the whole story. [Author's files]

Does Kim "bring this upon herself"? Or is the observer biased? The answer depends upon one's assumptions.

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