أنواع الأكسجين التفاعلية
Among birds, parrots live about 5-times longer than quail. Reactive oxygen species (ROS) production in heart, skeletal muscle, liver and intact erythrocytes was found to be similar in parrots and quail and showed no correspondence with longevity difference. These findings were concluded to cast doubt on the robustness of the oxidative stress theory of aging.