Negligible senescence

Negligible senescence describes organisms that show no measurable decline with age. They do not lose function, they do not face a rising risk of death, and they do not lose the ability to reproduce as they get older. Biogerontologist Caleb Finch coined the term in his 1990 book 'Longevity, Senescence, and the Genome'. He used it for species like certain rockfish, certain tortoises, and hydra. Naked mole-rats are often cited here too. But they show extremely slow, not strictly negligible, senescence, and they joined this discussion through later work (for example, Buffenstein 2008 onward). Negligible senescence is studied as a comparative-biology benchmark, to understand why most mammals, including you, do age.

Last reviewed: June 22, 2026

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