“…Both Ames dwarf and GHR−/− mice are remarkably long‐lived, with increases in longevity ranging from some 20% to over 60% depending on the diet, gender, and genetic background of the animal (Brown‐Borg et al ., ; Coschigano et al ., ; Bartke et al ., ). The enhancement of longevity in these mice is associated with maintenance of youthful levels of cognitive and neuromuscular function, and other phenotypic characteristics into advanced age (Bartke et al ., ), delayed onset, and reduced incidence of cancer and other age‐related pathological changes (Ikeno et al ., ; Bartke et al ., ), and a reduced rate of aging (Koopman et al ., ). We have previously proposed that the activation of BAT and increased metabolic rate in these long‐lived mice represent responses to increased radiational heat loss in these diminutive animals (Westbrook, ; Darcy et al ., ).…”