In "Consider the Lobster," an iconic essay written for Gourmet in 2004, David Foster Wallace described in painstaking detail the exceedingly strange life and times of America’s favorite seafood: the lobster. Examining the biology, behavior, and history of the brawny crustacean, Wallace found himself face to face with a creature so far removed from mammalian life it might as well have come from outer space. In its extraterrestrial weirdness, one characteristic of the lobster stood out: the apparent absence of aging.
Lobsters belong to a small group of organisms that largely defy senescence, the process of gradually succumbing to ones own metabolism commonly known as aging. Whereas most animals inevitably degrade and perish with time, animals of negligible senescence appear to live on indefinitely. In the absence of other threats, some of them can persist across centuries.
“The more scientists look, the more they find species that appear to be able to defy the aging process,” biologist Simon Watt said, speaking to The Daily Mail. “These species of course still die. They get diseases, they are injured or hunted. But unlike humans, they don’t die as a result of their own metabolisms — there doesn’t seem to be a built-in life expectancy in their cells.”
As a result, lobsters continue to grow throughout their entire life, developing a stronger shell with each molt. Although most are caught by fishermen or killed by infections at a relatively young age, some continue to thrive for decades. In 2009, a 20-pound specimen was estimated to be around 140 years old.
Scientists believe that the secret is telomerase — an enzyme that protects DNA by restricting cell death. In humans, the telomerase supply can only sustain a cell for about 50 divisions. Animals like the lobster, on the other hand, continue to express this enzyme throughout their entire life.
Lobsters, Immortality, and Evolution
Why, then, have so many species restricted their capacity to produce this rejuvenating substance? According to some biologist, the restriction may be part of the gross strategy of evolution. For some species, death is crucial to future life.
“In evolution, it doesn’t matter so much if something is good for the organism,” Watt explained. “What matters is that it is good for the gene — it allows the gene to be passed on.”
In this theory, telomerase expression is inversely proportional to an organism’s genetic need to reproduce sexually. Species like dogs, cats, and humans must unfold successively over generations in order to fend off deleterious mutations. To maintain the integrity of the gene, the biological situation must constantly be renewed, meaning new generations must rise as old generations fall, in order for genes to succeed.
But the benefits of renewed generations doesn't stop scientists from attempting to apply telomerase in efforts to defy aging and illness. Telomerase is currently inspiring a wide array of potentially life-saving treatments. Besides inducing “immortality” in weakened organs, a telomerase-regulating drug could withhold the substance from pernicious cell growths. Such drugs are already entering clinical trials as new candidates for cancer therapy.