For example, between 1976 and 2008, African Americans were victims of 329,825 homicides. Although there is a widespread perception that war is the most dangerous form of armed violence in the world, the average person living in a conflict-affected country had a risk of dying violently in the conflict of about 2.0 per 100,000 population between 2004 and 2007. This can be compared to the average world homicide rate of 7.6 per 100,000 people. This illustration highlights the value of accounting for all forms of armed violence rather than an exclusive focus on conflict related violence. Certainly, there are huge variations in the risk of dying from armed conflict at the national and subnational level, and the risk of dying violently in a conflict in specific countries remains extremely high. In Iraq, for example, the direct conflict death rate for 2004–07 was 65 per 100,000 people per year and, in Somalia, 24 per 100,000 people. This rate even reached peaks of 91 per 100,000 in Iraq in 2006 and 74 per 100,000 in Somalia in 2007. History
Scientific evidence for warfare has come from settled, sedentary communities. Some scholars argue humans may have a predisposition for violence (chimpanzees, also great apes, have been known to kill members of competing groups for resources like food), placing the origins of organized violence prior to modern settled societies.
Similarly, urban renewal projects such as business improvement districts have shown a reduction in youth violence.Different types of youth on youth violence include witnessing or being involved in physical, emotional and sexual abuse (e.g. physical attacks, bullying, rape), and violent acts like gang shootings and robberies. According to researchers in 2018, "More than half of children and adolescents living in cities have experienced some form of community violence." The violence "can also all take place under one roof, or in a given community or neighborhood and can happen at the same time or at different stages of life." Youth violence has immediate and long term adverse impact whether the individual was the recipient of the violence or a witness to it.Youth violence impacts individuals, their families, and society. Victims can have lifelong injuries which means ongoing doctor and hospital visits, the cost of which quickly add up. Since the victims of youth-on-youth violence may not be able to attend school or work because of their physical and/or mental injuries, it is often up to their family members to take care of them, including paying their daily living expenses and medical bills. Their caretakers may have to give up their jobs or work reduced hours to provide help to the victim of violence. This causes a further burden on society because the victim and maybe even their caretakers have to obtain government assistance to help pay their bills. Recent research has found that psychological trauma during childhood can change a childs brain.