Breathless--by choice.
During diving, hibernation and sleep, powerful inhibitory inputs act to produce breath holding and are periodically lifted to allow the expression of an intense drive to breathe. Many animals that do this also possess adaptations designed to prolong the periods of breath holding and shorten the periods of breathing.
Milsom
B
B
Zoology Department, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z4.
D000818:Animals; D001717:Birds / Q000502:physiology*; D004242:Diving / Q000502:physiology; D006454:Hemoglobins / Q000502:physiology; D006605:Hibernation / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology*; D012119:Respiration; D046048:Seals, Earless / Q000502:physiology*; D012890:Sleep / Q000502:physiology; D014907:Whales / Q000502:physiology*
D006454:Hemoglobins