Ageing gracefully: physiology but not behaviour declines with age in a diving seabird

Summary A higher proportion of long‐lived animals die from senescence than short‐lived animals, yet many long‐lived homeotherms show few signs of physiological ageing in the wild. This may, however, differ in long‐lived diving homeotherms that frequently encounter hypoxic conditions and have very high metabolic rates. To examine ageing within a long‐lived diving homeotherm, we studied resting metabolism and thyroid hormones ( N = 43), blood...