200 Years of Life: Who Is Taking Care of the Bowhead Whale

On the remote island of St Helena in the South Atlantic lives Jonathan, a Seychelles giant tortoise whose estimated birth year is around 1832. This means he may have begun his life when much of the modern world we know did not yet exist. Jonathan was already fully mature when he arrived on St Helena in 1882, although nobody was present to record the precise day or even year when he hatched. His documented history has nevertheless made him the oldest known living land animal, with an estimated age approaching two centuries.

Jonathan is old in ways that should also prevent us from romanticizing what extraordinary longevity means. He has developed cataracts and is virtually blind, his sense of smell has largely disappeared, and in his advanced age he receives nutritional support from the people who care for him. However, he continues to eat, move around his surroundings, respond to sound and participate, in the limited but unmistakable manner of an extremely old tortoise, in the continuing business of being alive.

Thousands of miles away, and in an environment that could hardly be more different from the grassy grounds of St Helena, another vertebrate presents an even more remarkable longevity story. The bowhead whale lives in the cold waters of the Arctic and sub-Arctic, where evidence from biological aging methods and historical hunting artifacts suggests that some bowhead whales can survive for more than two hundred years. An animal swimming beneath Arctic ice today could therefore conceivably have begun its life before automobiles, airplanes, antibiotics and most of the medical technologies that we now associate with extending human life.

Putting these two animals beside each other immediately creates an interesting problem for simple explanations about longevity. Jonathan is a terrestrial reptile and an ectotherm whose metabolic rate is low by mammalian standards, while the bowhead whale is an enormous marine mammal and an endotherm that must continuously generate and distribute heat within a body weighing many tonnes. One lives largely on land in the comparatively mild climate of St Helena, while the other spends its life moving through some of the coldest seawater inhabited by a mammal. Their histories, physiologies, body temperatures, environments, diets and patterns of energy expenditure are profoundly different, but they both have demonstrated an astonishing capacity to maintain a living vertebrate organism for approximately two centuries.

It is tempting, whenever we encounter an exceptionally long-lived animal, to immediately search for the particular mechanism that might explain its longevity. The tortoise may direct attention toward its slow metabolic rate, while the bowhead may direct attention toward unusually effective DNA repair, cancer resistance or other molecular characteristics that humans might eventually learn to reproduce. Comparative biology has already revealed fascinating differences in the cellular maintenance and repair systems of long-lived species. But individual mechanisms do not remove the larger biological requirement, because whatever mechanisms are involved must ultimately allow the organism to continue performing the work required to remain alive.

Jonathan did not hatch around 1832 containing enough biological material to last until 2026, nor did a bowhead whale born two centuries ago begin life with a supply of biological material that could simply last for two hundred years. Living organisms cannot operate that way because life continuously uses, transforms, repairs, replaces and exports matter.

Every day that Jonathan has remained alive, he has eaten, digested food, moved, responded to his surroundings, repaired damage and replaced some of what has been worn out along the way. These processes may occur at a slower pace than they do in many other animals, but slow does not mean absent, because a living tortoise is not a sealed container whose contents simply remain undisturbed for two hundred years. Whatever explains Jonathan’s extraordinary longevity must therefore allow the ordinary work of staying alive to continue for an extraordinary length of time.

The bowhead makes the same point from a very different setting, because an enormous mammal swimming through Arctic water has also been continuously doing the ordinary work required to remain alive. It must feed, breathe, move, maintain its body temperature, repair damage and respond to an environment that is very different from Jonathan’s life on land. Whatever allows a bowhead whale to survive for two centuries must therefore keep this ordinary biological work going for an extraordinary length of time.

Neither animal therefore survives by avoiding the work of living, because both have survived while continuing to do it. Modern discussions about longevity often focus on what might be added, changed or deliberately manipulated to extend life, whether through diet, exercise, medications, supplements or other interventions. These are important areas of investigation, but neither Jonathan nor the bowhead could have reached such an extraordinary age unless the ordinary biological work required to remain alive had continued successfully throughout those years.

Longevity discourse often turns toward the more exciting possibilities of renewal and rejuvenation, while the ordinary work of maintenance can appear almost boring by comparison. Exceptional longevity cannot simply mean the absence of damage or the avoidance of biological activity, because remaining alive for a very long time requires the continuing preservation of enough function for the organism to keep going. Jonathan has not remained unchanged for nearly two centuries, nor has the bowhead somehow escaped the ordinary demands of being alive. Their remarkable longevity therefore does not place the biology of renewal exclusively within rejuvenation, but also shows how much renewal has already been occurring within the continuing work of maintenance.

What is particularly interesting about Jonathan and the bowhead is not simply how much energy either animal uses, but how successfully biological organization has been preserved while energy and matter continue to flow through the organism over extraordinary periods of time. Every additional year provides more opportunities for damage, wear and disruption, and a two-hundred-year lifespan does not mean that these processes never occur. It means that, for an extraordinarily long period, their accumulated consequences have not exceeded the organism’s ability to preserve enough function to remain alive.

Jonathan makes this particularly visible because he has clearly aged. His cataracts tell us that longevity did not freeze his tissues in youth, and his loss of smell tells us that nearly two centuries of life did not occur without functional decline. The remarkable fact is not that Jonathan remained biologically young for almost two hundred years, but that sufficient function has been preserved across enough systems for the whole animal to remain alive despite becoming extraordinarily old.

This may be one of the most useful implications of long-lived animals for understanding human longevity, because exceptional longevity is not the same thing as the absence of aging. An organism can accumulate imperfections, lose some capacities and require increasing support while still maintaining enough coordination and reserve to continue functioning as an organism. Aging and living are therefore not opposites, because for most of life they occur together.

The bowhead presents the same problem at a molecular level. Researchers studying its extraordinary lifespan have identified unusual characteristics of DNA maintenance, cellular stress responses and other protective systems, including evidence of highly effective repair of potentially dangerous DNA double-strand breaks. Such findings are important because they shift attention away from the idea that a long-lived organism simply experiences less damage and toward the possibility that damage continues to occur while the organism remains unusually capable of detecting, repairing, tolerating or removing its consequences before they threaten the integrity of the whole system.

Somewhere beneath Arctic ice, a bowhead whale may have been swimming for longer than any human lifetime. For most of that time, there was no veterinarian following it through the ocean, no longevity clinic measuring its biomarkers, no carefully designed supplement program and no physician periodically adjusting a treatment plan.

Who, then, has been taking care of the bowhead whale? The answer, for most of those two centuries, has been the whale’s own biology. This is not an argument against medicine, veterinary care, nutrition or any other external intervention, because Jonathan now benefits from human care, including supplemental feeding appropriate to his advanced age, just as human beings routinely benefit from interventions that support biological systems when their own capacity becomes insufficient. The more fundamental point is simply one of sequence. Medicine can assist biological maintenance, replace something that has been lost, remove a threat, reduce an excessive burden or help restore a failing function, but the underlying processes of maintenance were operating long before an intervention became necessary. Jonathan’s biology has been doing this work for almost two centuries.

This is why animals such as Jonathan and the bowhead are so useful when thinking about longevity. They pull our attention away, if only temporarily, from the search for something that can be added from outside and redirect it toward the astonishing collection of processes already occurring inside every living organism. Longevity is therefore not merely a measurement of elapsed time and certainly not evidence that nothing has gone wrong during that time, but despite everything that has gone wrong, enough has continued to go right.

One animal has spent almost two centuries slowly moving across land, while another may spend even longer moving beneath Arctic water. One is an ectothermic reptile and the other an endothermic mammal with profoundly different physiologies and environments, yet together they leave open the upstream question of what a living system must continue doing if it is to remain alive for two hundred years.

Longevity may ultimately be the ability to continue changing without losing the ability to remain alive.

Mukaila Kareem is a doctor of physiotherapy and founder of metabolichealthliteracy.com