Intergenerational Transmission of Income:

Bryan Caplan:

"(late 1990s – today): The intergenerational income correlation is indeed quite high. But twin and adoption studies show that most or all of this correlation stems from heredity. The reason why kids from rich families do well isn’t that mom and dad buy their way through life. The reason, rather, is that rich families have genes that cause financial success, and pass these genes on to their kids. (Casual consumers of this literature often get confused by the fact that the effect of IQ is far too small to explain the intergenerational income correlation. The key thing to remember is that there is a lot more to genetics and success than IQ)."