These Fish Could Help Us Live Longer — If We Don’t Eat Them All First

It’s still something of a mystery that a mouse only lives a year or two, a dog maybe 12, and a human about 80. Researchers disagree about the causes for such stark differences in longevity. Finding the answer might point to new strategies for aging-related diseases — cancer, Alzheimer’s, heart disease and diabetes. Or perhaps medical science would finally coax human beings past what appears to be a hard limit of about 120 years.

Some scientists are looking for answers among weirdly long-lived animals — reptiles and fish that can keep going well beyond 200 years. There’s even a species of clam that can live to 500. What makes many of these ancient animals interesting is not just their quantity of life but the quality — most don’t show any decline, but instead keep fighting predators, hunting and reproducing decade after decade.