Read this whole post by Ed Yong at Discover. It seems that the creationists are half right. Sure enough, we have not evolved from the monkeys — we have instead devolved from them.
The anxiety caused by human inequality is unlike anything observed in the natural world. In order to emphasize this point, Robert Sapolsky put all kidding aside and was uncharacteristically grim when describing the affects of human poverty on the incidence of stress-related disease.
“When humans invented poverty,” Sapolsky wrote, “they came up with a way of subjugating the low-ranking like nothing ever before seen in the primate world.”
This is clearly seen in studies looking at human inequality and the rates of maternal infanticide. The World Health Organization Report on Violence and Health reported a strong association between global inequality and child abuse, with the largest incidence in communities with “high levels of unemployment and concentrated poverty.” Another international study published by the American Journal of Psychiatry analyzed infanticide data from 17 countries and found an unmistakable “pattern of powerlessness, poverty, and alienation in the lives of the women studied.”
The United States currently leads the developed world with the highest maternal infanticide rate (an average of 8 deaths for every 100,000 live births, more than twice the rate of Canada). In a systematic analysis of maternal infanticide in the U.S., DeAnn Gauthier and colleagues at the University of Louisiana at Lafayette concluded that this dubious honor falls on us because “extreme poverty amid extreme wealth is conducive to stress-related violence.” Consequently, the highest levels of maternal infanticide were found, not in the poorest states, but in those with the greatest disparity between wealth and poverty (such as Colorado, Oklahoma, and New York with rates 3 to 5 times the national average). According to these researchers, inequality is literally killing our kids.