Research has shown that parents with high incomes tend to have children who score highly in IQ tests. It is very unlikely that this is because having rich parents improves one’s IQ. Much more likely is that being intelligent tends to result in having a high income, since a high level of intelligence is required for entering well-paid professions such as medicine and law. The research did not examine whether the relationship between parental income and children’s IQ scores was dependent on the nature of the parents’ profession. If it were found that the children of high earners in sport and entertainment did not generally have high IQ scores, we could conclude that the intelligence level of children is largely genetically inherited from their parents.