American lobsters have made a deal with the devil for everlasting youth. But like any Faustian bargain, this deal has its consequences.
Lobsters are known for being unusually resilient in that they don’t truly age. Instead, they continue growing and reproducing their entire lives. As they grow, they shed their exoskeletons and form new ones to accommodate their new size.
One possible explanation for lobsters’ longevity is telomerase - an enzyme that lengthens the telomeres on their ends of their chromosomes. In humans, telomeres eventually shorten as chromosomes replicate, leading to senescence, or deterioration with age. We experience the loss of our faculties, increased susceptibility to disease, and increased death rate, among other effects.
Lobsters, however, don’t experience this the same way that we do. Their metabolism stays at the same rate, and they retain their ability to reproduce. In fact, a bigger body translates to more reproductive success, as the females can produce and carry more eggs.
However, there is a downside to this deal. Although lobsters don’t lose the function of their bodies as they age, they can still die. As they grow, it becomes more and more energetically taxing for them to molt and grow a new exoskeleton. Even though their metabolism doesn’t slow down, eventually it becomes insufficient to molt at such a high level. This leaves the lobster unable to escape its shell, dying of shell disease or other resultant infections. This is the closest to dying of old age that lobsters experience, and usually happens around 31 years for males and 54 years for females.
Lobsters get the advantage of indefinite growth, but at the cost of dying trapped, with their own shells rotting around them. Is it worth it? You’d have to ask a lobster.