The animal known to have the longest lifespan is the Greenland shark (Somniosus microcephalus), with some estimates suggesting they can live for over 400 years. Research using radiocarbon dating techniques indicated that some individuals might reach ages well beyond what was previously believed possible for vertebrates. Greenland sharks inhabit cold Arctic and sub-Arctic waters, growing slowly and reaching sexual maturity around 150 years of age. Their incredible longevity is attributed to their cold, deep-water habitat, which slows their metabolism and development. This remarkable lifespan raises fascinating questions about aging and survival in extreme environments.