Wednesday, September 29, 2010
Friday, September 24, 2010
SciAm Article on Aging
The Sept issue of Scientific American is a special issue on "the end". It includes this fascinating article by one of the leading experts on aging. Here are a few excerpts:
IF YOU WERE GIVEN a free hand to plan how your life will end—your last weeks, days, hours and minutes—what would you choose? Would you, for example, want to remain in great shape right up until the last minute and then go quickly? Many people say they would choose that option, but I see an important catch. If you are feeling fine one moment, the very last thing you would want is to drop dead the next. And for your loving family and friends, who would suffer instant bereavement, your sudden death would be a cruel loss. On the other hand, coping with a long, drawn-out terminal illness is not great either, nor is the nightmare of losing a loved one into the dark wastes of dementia.
We all prefer to avoid thinking about the end of life. Yet it is healthy to ask such questions, at least sometimes, for ourselves and to correctly define the goals of medical policy and research. It is also important to ask just how far science can help in efforts to cheat death.
....By far the majority of natural organisms die at relatively young ages because of accidents, predation, infection or starvation. Wild mice, for example, are at the mercy of a very dangerous environment. They are killed rather quickly—it is rare for a wild mouse to see its first birthday. Bats on the other hand are safer because they can fly.
Meanwhile maintenance of the body is expensive, and resources are usually limited. Out of the daily intake of energy, some might go to growth, some to physical work and movement, some to reproduction.
....Here is where the disposable soma theory comes in. The theory posits that, like the human manufacturer of an everyday product—a car or a coat, for example—evolving species have to make trade-offs. It does not pay to invest in allowing indefinite survival if the environment is likely to bring death within a fairly predictable time frame. For the species to survive, a genome basically needs to keep an organism in good shape and enable it to reproduce successfully within that time span.
....Using the science of aging to improve the end of life represents a challenge, perhaps the greatest yet to face medical science. Solutions will not come easily, despite the claims made by the merchants of immortality who assert that caloric restriction or dietary supplements, such as resveratrol, may allow us to live longer. The greatest human ingenuity will be needed to meet this challenge. I believe we can and will develop treatments targeted at easing our final years. But when the end arrives, each of us—alone—will need to come to terms with our own mortality. All the more reason then to focus on living—on making the most of the time of our lives, because no magic elixir will save us.
Global Survey on Scientific Literacy
NatureNews has the scoop on a new global survey of scientific literacy. A sample from the story:
Science, it is often said, is an international language. But how international are attitudes towards science and scientists? Nature and our affiliated publication Scientific American set out to learn how the views of the scientifically literate public vary around the world. Our web-based survey of more than 21,000 readers of Scientific American and its translated editions in 18 countries revealed that although these science enthusiasts read the same publication and share many attitudes in their perception of science, they seem to diverge on some of the hottest-button issues.
The differences are most striking between east Asia and the rest of the world. For example, a startling 35% of the Japanese and 49% of the Chinese respondents agreed that there is "reason for doubt" about evolutionary theory's ability to explain the variety of species on Earth. In contrast, the numbers for the rest of the world fluctuated around 10%. Japanese and Chinese respondents were also less likely than others to say that they trust scientific explanations of the origins of the Universe. And almost one-third of scientifically literate Chinese people say that scientists should not get involved in politics, compared with around 10% of respondents in most of the rest of the world.
Sunday, September 19, 2010
Play Menu (Sept. 2010)
Sunday, September 12, 2010
Paper on Human Male Reproductive Senescence
The latest issue of the Annals of the NY Academy of Sciences has this interesting paper on human male reproductive senescence. Here is the abstract:
Unlike menopause, male reproductive senescence does not involve an acute drop in fertility. Men do, however, manifest distinct changes in somatic and gonadal function with age. Moreover, population variation in male reproductive senescence reveals phenotypic plasticity resulting from environmental, lifestyle, and genetic factors. An evolutionary and life history perspective is vital for understanding male reproductive senescence because aging involves biological constraint as well as adjustments to reproductive strategies and the allocation of somatic resources. An awareness of life history–related tradeoffs between energetic and time constraints is especially useful because biological aspects of male senescence are products of environmental challenges and natural selection. This article reviews the adaptive significance of the evolutionary biology of human male senescence with particular attention to population variation. An evolutionary perspective cannot only shed light on the origins and biology of human male senescence but also provide insights into contemporary issues of male aging and health.
Thursday, September 09, 2010
Bioethics Paper Now Published
My paper entitled "Equality and the Duty to Retard Human Ageing" is now published in the latest issue of Bioethics. Here is the abstract:
Where does the aspiration to retard human ageing fit in the ‘big picture’ of medical necessities and the requirements of just healthcare? Is there a duty to retard human ageing? And if so, how much should we invest in the basic science that studies the biology of ageing and could lead to interventions that modify the biological processes of human ageing? I consider two prominent accounts of equality and just healthcare – Norman Daniels's application of the principle of fair equality of opportunity and Ronald Dworkin's account of equality of resources – and conclude that, once suitably amended and revised, both actually support the conclusion that anti-ageing research is important and could lead to interventions that ought to be considered ‘medical necessities’.
Saturday, September 04, 2010
FDA Preliminary Analysis of Genetically Modified Salmon
The Globe has the scoop here. A sample:
Salmon engineered in Eastern Canada to grow twice as fast as their wild counterparts are poised to become the first genetically modified animal approved for human consumption in North America.
The DNA-altered salmon are “as safe to eat as food as other Atlantic salmon” and have “no biologically relevant differences,” the United States Food and Drug Administration said in a preliminary analysis of the fish released Friday. The federal food regulator is set to hold three days’ worth of public hearings later this month to review questions over whether the salmon are safe to eat and safe for the environment – a step widely perceived as one of the fish’s final hurdles to entering the human food chain.
....“Instead of flying salmon from the south of Chile or from the North Atlantic or Norway, it’s possible to grow salmon closer to consumption centres, reducing their environmental footprint,” he said. And the fish’s double-fast growth rate also offers a potential solution for those concerned with mitigating the impending global food shortage, he said.
“The world population will reach nine billion people in 20 years,” he said. “At that rate, it’s hard to imagine how we will develop food systems able to sustain that world. This technology will be part of the solution.”