Researchers measured the participants IQs at ages 5 and 10, then followed up with them at ages 16 and 30, asking about symptoms of psychological distress and drug use as part of a larger survey.
The question perplexed people for years, until, in the 1950s, a German scientist named Gustave Kramer provided some answers and, in the process, raised new questions.
This divergence on such an important question is not a calamity, and so far as it causes us to be occupied with the problem at the present time is a matter for rejoicing.
About 8 million people have blood flow problems to their legs and hips, known as peripheral artery disease, according to the American Heart Association.
While more people are living longer and healthier lives, gaps are widening between the rich and the poor in some nations and tens of millions of people are vulnerable to food and water shortages.