above-average intelligence in Ashkenazi Jews — those of northern European heritage — resulted from natural selection in medieval Europe, where they were pressured into jobs as financiers, traders, managers and tax collectors. Those who were smarter succeeded, grew wealthy and had bigger families to pass on their genes, they suggested. That evolution also is linked to genetic diseases such as Tay-Sachs and Gaucher in Jews. The new study was funded by the Department of Energy, the National Institute of Mental Health, the National Institute of Aging, the Unz Foundation, the University of Utah and the University of Wisconsin.