Excellent review of Jonathan Silvertown's new book The Long and the Short of It: The Science of Life Span and Aging
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Mr. Silvertown, a professor of ecology at Britain’s Open University, will not teach you how to live forever. Rather, he swoops like a barn swallow (life span 16 years) across a terrain encompassing the long-lived ponderosa pine (300 years) and the evanescent nematode worm C. elegans (days to weeks), with nods to Oliver Wendell Holmes Jr. (93 years), Dylan Thomas (49 years) and Woody Allen (still ticking) to demonstrate why, even though you personally are probably limited to less than a century, you are still a particularly lucky conglomeration of organic matter in life’s long mortal parade.
“The puzzle of longevity,” Mr. Silvertown points out, “is not why we die so soon but rather why we live so long.” For most of history, living creatures were single cells that reproduced by dividing. But once evolution produced multicellularity, reproduction and survival were separated, and hemmed in by new risk-benefit calculations. Cell division had to persist for purposes of reproduction and repair, but it also had to be controlled, for uncontrolled division means cancer (“a brutal reminder that long life is a precarious achievement”).
The cancer cells of Henrietta Lacks (immortalized in laboratories everywhere, as well as in Rebecca Skloot’s best-selling book) demonstrate that under the right circumstances, mammalian cells can survive more or less forever. But the life span of whole beings is inextricably linked to nutrition, environment and genetics, all operating under an evolutionary mandate to optimize the species.
:Mr. Silvertown, a professor of ecology at Britain’s Open University, will not teach you how to live forever. Rather, he swoops like a barn swallow (life span 16 years) across a terrain encompassing the long-lived ponderosa pine (300 years) and the evanescent nematode worm C. elegans (days to weeks), with nods to Oliver Wendell Holmes Jr. (93 years), Dylan Thomas (49 years) and Woody Allen (still ticking) to demonstrate why, even though you personally are probably limited to less than a century, you are still a particularly lucky conglomeration of organic matter in life’s long mortal parade.
“The puzzle of longevity,” Mr. Silvertown points out, “is not why we die so soon but rather why we live so long.” For most of history, living creatures were single cells that reproduced by dividing. But once evolution produced multicellularity, reproduction and survival were separated, and hemmed in by new risk-benefit calculations. Cell division had to persist for purposes of reproduction and repair, but it also had to be controlled, for uncontrolled division means cancer (“a brutal reminder that long life is a precarious achievement”).
The cancer cells of Henrietta Lacks (immortalized in laboratories everywhere, as well as in Rebecca Skloot’s best-selling book) demonstrate that under the right circumstances, mammalian cells can survive more or less forever. But the life span of whole beings is inextricably linked to nutrition, environment and genetics, all operating under an evolutionary mandate to optimize the species.
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