Estación Experimental de Zonas Áridas (EEZA-CSIC), E-04120 Almería, Spain.
Dpto de Ecología, Universidad de Granada, E-18071 Granada, Spain.
Nature. 2016 Oct 13;538(7624):233-237. doi: 10.1038/nature19758. Epub 2016 Sep 28.
The psychological, sociological and evolutionary roots of conspecific violence in humans are still debated, despite attracting the attention of intellectuals for over two millennia. Here we propose a conceptual approach towards understanding these roots based on the assumption that aggression in mammals, including humans, has a significant phylogenetic component. By compiling sources of mortality from a comprehensive sample of mammals, we assessed the percentage of deaths due to conspecifics and, using phylogenetic comparative tools, predicted this value for humans. The proportion of human deaths phylogenetically predicted to be caused by interpersonal violence stood at 2%. This value was similar to the one phylogenetically inferred for the evolutionary ancestor of primates and apes, indicating that a certain level of lethal violence arises owing to our position within the phylogeny of mammals. It was also similar to the percentage seen in prehistoric bands and tribes, indicating that we were as lethally violent then as common mammalian evolutionary history would predict. However, the level of lethal violence has changed through human history and can be associated with changes in the socio-political organization of human populations. Our study provides a detailed phylogenetic and historical context against which to compare levels of lethal violence observed throughout our history.
尽管人类同物种间暴力行为的心理、社会学和进化根源已经吸引了学者们两千多年的关注，但至今仍存在争议。在这里，我们提出了一种理解这些根源的概念方法，假设哺乳动物（包括人类）的攻击性具有重要的系统发育成分。通过编译来自哺乳动物综合样本的死亡率来源，我们评估了由于同物种导致的死亡比例，并使用系统发育比较工具，预测了人类的这一数值。从系统发育上预测的人际暴力导致的人类死亡比例为 2%。这一数值与灵长类动物和猿类进化祖先的系统发育推断值相似，表明由于我们在哺乳动物系统发育中的位置，一定程度的致命暴力是存在的。这也与史前部落和部落的百分比相似，表明我们在那时和哺乳动物的共同进化历史所预测的一样具有致命的暴力倾向。然而，通过人类历史可以看出，致命暴力的水平发生了变化，并且可以与人类种群的社会政治组织变化相关联。我们的研究提供了一个详细的系统发育和历史背景，可用于比较我们历史上观察到的致命暴力水平。
