More intelligent people live longer - and we could propose all sorts of mundane and obvious reasons as to why this is the case, such as a greater and more effective use of health knowledge and medical resources. Here, a researcher proposes that there is in fact a biological reason as well: "Intelligent people live longer - the correlation is as strong as that between smoking and premature death. But the reason is not fully understood. Beyond simply making wiser choices in life, these people also may have biology working in their favor. Now research in honeybees offers evidence that learning ability is indeed linked with a general capacity to withstand one of the rigors of aging - namely, oxidative stress. Ian Deary, a psychologist at the University of Edinburgh, has proposed the term 'system integrity' for the possible biological link between intelligence and long life: in his conception, a well-wired system not only performs better on mental tests but is less susceptible to environmental onslaughts. Gro Amdam of Arizona State University and the Norwegian University of Life Sciences was intrigued by the idea and last year devised a way to test it in bees. ... Amdam hypothesizes that the ability to handle stress could be a component of system integrity; better overall stress resilience may contribute to both higher IQ scores and longer life. And if scientists can unravel what underlies these biological differences, they might be able to alleviate inborn disparities."