Colin Farrelly notes a Tom Kirkwood piece on longevity and aging: "The increase in human life expectancy over the past ten years has taken both scientists and the population generally by surprise. Until recently, demographers were confidently predicting that once the gains made by reducing mortality in early and middle life had reached completion, growth in longevity would stop and we would see the fixed reality of the ageing process. This has not happened. ... The continuing increase in life expectancy, which in many countries advances by several hours per day, is one of humanity's most astonishing successes. ... Age is by far the biggest risk factor for a wide range of clinical conditions that are prevalent today. One might therefore presume that a major effort is being made to understand the ways in which ageing renders the elderly more vulnerable to pathology. Nothing could be further from the truth. There is a large number of medical research institutes around the world, many with a focus on one or more of the major age-related diseases - cancer, heart disease, arthritis or dementia. Yet only a tiny fraction of these carries out any research on the intrinsic contribution from the ageing process itself."