There is a social bias against the idea of aggression, so that many people conflate the ideas of aggression and violence, so that they cannot separate them. This suggests that aggression is negative, which is not necessarily the case. The result has been that suggestions that aggression is somehow genetic have been morphed into the notion that people carrying those genes must somehow be inferior to the rest of the population. This is untrue on a number of different levels. First, it assumes that aggression must be negative. Second, it assumes that acting on aggressive behavior must be a maladaptive behavior. Neither of those assumptions is warranted. However, they highlight some of the pitfalls in examining aggression.
Examining the whether aggression can be inherited is a very morally risky topic. It cannot be ignored that prior attempts to link genetics and anti-social behavior, such as aggression, have been used as a way to reinforce racial stereotypes and engage in prejudiced behavior and enact prejudiced policies. However, it also cannot be ignored that while linking heritability with aggression can have potentially negative social and policy consequences, there does appear to be some evidence that aspects of anti-social behavior, including aggression, may have a genetic basis. If it does, then it seems important to understand the nature and extent of the heritability of aggression, so that it is possible to limit or channel naturally-occurring aggression while not penalizing people for having an inherited predisposition towards greater violence than average.
It does appear that, at this point in time, scientists are willing to revisit the idea that aggression may an inherited component. The tainted history of using biology to explain criminal behavior has pushed criminologists to reject or ignore genetics and concentrate on social causes: miserable poverty, corrosive addictions, and guns. Now that the human genome has been sequenced, and scientists are studying the genetics of areas as varied as alcoholism and party affiliation, criminologists are cautiously returning to the subject" (Cohen, 2011). However, it is important that any results be viewed in a cautionary manner because of the way that hereditary links to violence or aggression have been used do discriminate against groups of people. It is critical to keep in mind that "genes are ruled by the environment, which can either mute or aggravate violent impulses. Many people with the same genetic tendency for aggressiveness will never throw a punch, while others without it could be career criminals" (Cohen, 2011). Therefore, it is important to consider how environmental factors mediate and impact genetic factors.
Studying the possible genetic influence of aggression began in earnest in the late 20th century, and transformed from a scientific goal to a social movement. "Francis Galton, who coined the term eugenics in 1883, perceived it as a moral philosophy to improve humanity by encouraging the ablest and healthiest people to have more children" (Carlson, n.d.). However, the positive view of eugenics, while gaining some social support, did not last. Instead, many people began to concentrate on negative eugenics, which suggested that some people should not reproduce because of their faulty genes. This led to atrocities in many of the countries that subscribed to the theory that negative traits were inherited. These atrocities included things like forced sterilizations in the United States. Eugenics also played a huge part in the success of the Nazi party in Germany because of the idea that the Jews were somehow genetically inferior. In fact, it was only after Nazi atrocities began to receive a significant amount of negative publicity that people in the U.S. And the rest of Europe began to back away from embracing some of the aspects of negative eugenics, and this included a movement away from looking at hereditary aspects of aggression.
However, even while it became increasingly unpopular to suggest that certain antisocial behaviors, including aggression, had a genetic component, it also became clearer that there did appear to be some hereditary component. Succinctly put, research was providing evidence to support the anecdotal observation that "aggression and antisocial behavior run in families" (Miles & Carey, 1997). Not all of these studies look specifically at the aggression dimension. Instead, aggression has been measured in a number of different ways: delinquency, criminality, conduct disorders, and antisocial personality (Miles & Carey, 1997). However, the fact that these studies found that this type of behavior runs in families is not the same as finding that they are genetic. "Although similarity among family members for aggressive or antisocial behavior has been evident, the study of intact nuclear families has not been able to trace this similarity to shared genetic influences, shared familial environmental factors, or some combination of both genes and environment" (Miles & Carey, 1997). Therefore, it was important to look at whether genetic influences alone could be indicative of a greater propensity towards aggression. Not surprisingly, early researchers examined different twin studies and looked at the behavior correlation between adopted children and their biological parents. These studies supported the idea that aggression has a hereditary component, but also made it clear that the genetic component played only a partial role in predicting whether or not someone would be aggressive.
In order to fully understand what it means to investigate the heritability of aggression, it is important to understand what researchers mean by aggression. In the context of studies examining aggression and heredity, aggression appears to be linked to anger and the negative impact of aggression. Therefore, depending on the researcher, aggression may be used interchangeably with propensity for violence, criminality, anti-social behavior, and even an inability to concentrate. In fact, aggression seems interchangeable with the concept of anger and the ability to control anger. In other words, the research examines how easily someone experiences anger as well as how that person is able to control anger and angry impulses. "Aggression has been de-ned as behavior produced to cause physical harm or humiliation to another person who wishes to avoid it (Baron & Richardson, 1994). Although this de-nition is functional, it does re-ect a potential bias in assuming that aggression is inherently bad. In other words, the de-nition above is de-ned in such a way as to imply that the aggressor is a "perpetrator" and the aggression recipient is a "victim." As such, this is an incomplete de-nition of aggression" (Ferguson & Beaver, 2009). It is also important to keep in mind that aggression is different from violence. If one thinks of violence as the nonconsensual use of force or power against another person, then it seems clear that almost all violent behavior would be aggressive, though some may challenge whether the use of violence in self-defense qualifies as violent or aggressive behavior. Moreover, while "violent behavior certainly would be aggressive, but not all aggressive behaviors are violent or even necessarily negative from a cultural perspective" (Ferguson & Beaver, 2009). Instead, there is a continuum of aggression, but this continuum is not always captured in research on aggression.
As the example above makes clear, the working definitions of aggression are somewhat limited. What these historical examples have refused to consider is that aggression is not a wholly negative adaptation. Obviously, from an evolutionary standpoint, it makes sense that more aggressive people would be more likely to survive and prosper than people who are not aggressive because there has always been competition over resources and those who were more aggressive were more likely to obtain the resources. On the other hand, people who were so aggressive as to place themselves outside of the protection of the group were probably less likely to be able to successfully pass on their genes. The conclusion is that, while too much aggression is undesirable, some aggression is acceptable. Moreover, the level of acceptable aggression is going to be context dependent. What is considered acceptable aggression in battle is going to differ significantly from acceptable behavior in a boardroom. Moreover, aggression does not mean that someone is engaging in a violent manner. "Acceptable aggression expressed in judging or subduing others is also a safety valve for discharging remaining pent-up aggression (Fauteux, 1994).
The reason that the heredity of acceptable aggression is not a research topic is because acceptable aggression is not noteworthy. Presumably, the vast majority of people in society exhibit acceptable levels of aggression. Those who are too aggressive would be pushed out of the group, while those who do not exhibit enough aggression would presumably not survive. Furthermore, while those who do not exhibit sufficient aggression may be outside of normal parameters, they are unlikely to be the source of problems for society, unlike those who exhibit too much aggression. Therefore, studies focusing on aggression have focused on those who are considered overly aggressive.
Furthermore, studies of aggression tend to focus on aggression that has been expressed through some behavior. In this way, aggression is treated as a verb. However, aggression is also a noun. A person experiences aggressive feelings and instincts, even if the person…