Male aggression as a reproductive strategy

male aggression

Origins of aggression can be better understood if viewed through the lens of sexual benefits that it provides. Combative behavior finds its justification in the need for males to protect their territory and resources, and to conquer the female and to reproduce – these are the adaptive and evolutionary significances of aggression. Namely because of competition for reproductive success there are a strongly asymmetric behavior between males and females in many animal species and this asymmetry in heavily is true for humans.

Men have always had the tendency to possess more women and this was the main cause of the masculine aggressiveness and homicides, not just in archaic or tribal societies, but also in the contemporary, more or less advanced ones [Gat, 2010]. The sexual competition between men has been and still is more intense than between women. Women do not form military coalitions, they are not motivated to start a war and to participate in fights not only because of their physical constitution, but also because the success of a woman in the reproduction process is seldom dependent on the high number of available men; in the case of women, to have more men does not mean to have more babies.

The women’s risk of being hurt or killed in a fight outdoes a lot of reproductive status-related advantages which they could obtain if they would achieve as a result of an eventual victory in a physical competition for men. For men, however, there were much more reasons for them to train in dangerous fights, because the risk was justified and compensated by the access to much more women, who were bearing them more children and were ensuring the genetic continuity of these men-aggressors [Pinker, 1997/2009, p. 586].

Generally speaking, from the evolutionary point of view, it’s successful not the individual that manages to survive longer, but the one that has more descendants. Let us make a distinction between physiological survival (namely of the individual) and the genetic survival (throughout the genes that are distributed to other generations of that individual); the genetic survival has priority and the access to more women has guaranteed mainly this type of survival, the genetic one, even if the life of the individual is at risk.

One of the brightest scientific explanations, regarding these evolutionary processes belongs to the renown English ethologist Richard Dawkins. He proposed the thesis of the so called “selfish gene”, which says that the basic elements of the evolution are genes, not the individuals or the species. According to the scientific vision that Dawkins developed, genes pass from one generation to another as the main evolutionary subject, and the bodies are like some vehicles that ensure this transmission. In his book, “The Extended Phenotype: The Long Reach of the Gene”, Dawkins explains that the genes manipulate the environment and shape it in such a way, that it facilitates their reproduction [Dawkins, 1982].

In other words, the genes facilitate the manifestation of those behaviors that would, at their turn, ensure the reproduction of these genes. Aggressive behavior is part of this category. From the perspective of the thesis that Dawkins endorses, the genes that are responsible for the aggressive behavior favors the owners of these genes in competitive fights and, respectively, because of the competitive advantages of the concerned individuals, the “aggression genes” are themselves very well-promoted in a society.

Even if an aggressive behavior can be detrimental to the individual and can lead, ultimately, to a premature death, from the perspective of the “aggression genes” the risks and the personal loss of the individual are justified, as long as he manages to gain a couple of offspring from his sexual conquests. Thanks to this evolutionary logic, we understand why some psychological and behavioral traits, like aggressiveness, are so durable. The primitive times have passed a long ago, nonetheless, the primitive instincts are as lively as tens and hundreds of thousands years ago. Nowadays, people, at the level of psychological predispositions, are almost as aggressive as the people from the Paleolithic age. The persistence of aggressiveness, its transmission from one generation to another is possible because of the sexual advantages that it ensured.

A lot of specialized studies have subscribed in favor of the thesis about the genetic and reproductive stake of the aggressive behavior. Such conclusions emerge, for instance, from the results of the study that was published in 2008 by the ethologists Laurent Lehmann and Marcus W. Feldman, from Stanford University, USA; according to them, the warlike behavioral tempers have been sent from one generation to another, hereditarily amassing themselves, thanks to the increased access of the more aggressive and combative individuals to women and resources.

The more aggressive and skillful fighters have had access to more resources and conquered women and, respectively, have had higher chances to transmit their genes. The ethologists’ studies have targeted both the aggressive behavior of primates and the way in which the human communities have developed, before the formation of states and the establishment of borders, as well as the advantages that a group obtains by multiplying, at the level of population, the hereditary traits that stimulate the manifestation of aggressiveness. Finally, Lehman and Feldman nominated a behavioral model, backed up by mathematical equations, which explains the evolutionary logic of existence and the prolificacy of the genes linked with belligerence and bravery [Lehmann, Feldman, 2008].

At his turn, the Austrian ethologist Eibl-Eibesfeldt explained the evolutionary process of the spreading of the “genes of aggressiveness” inside groups this way: The groups that survive are the always the ones that have the most combative and brave warriors. The defeated individual is always killed, banished or represses and, therefore, culturally destroyed. In this latter case, his genetic background is taken by the winners. The war has favored for a long time, in the human history, the selection of warlike spirit and aggressiveness. The human history for up to this point is the history of the victorious conquerors [Eibl-Eibesfeldt, 1975/2009, p. 266].

The evolutionary psychology researcher, Leda Cosmides, has frontally approached the phenomenon of masculine aggressiveness: she says that on the question “Why would someone be so stupid, as to start a war?”, there is only one acceptable answer: “for women’s sake.” The risk of dying for alimentary resources is, from the evolution’s point of view, less justified than the risk of dying for the sake of getting a woman [apud Dennen van der, 1995, p. 328-331].

Withal, researches showed that men are more likely than women to make a choice of causing three same sex deaths to save one opposite sex life; and this choice is more likely when there are fewer potential sexual partners, more likely for heterosexual men and less likely if the female character to be saved no longer has reproductive value [Trémolière et al., 2014].

In other words, men are willing to kill for the opportunity to reproduce.


© Dorian Furtuna, ethologist


Photo: Warrior, Mursi Tribe, Ethiopia; /

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