Chimpanzees, like humans, are mammals that rely on lungs to exchange oxygen and carbon dioxide. Their respiratory system works through three main phases:
1. Inhalation
When a chimpanzee inhales, the diaphragm contracts and moves downward, while the intercostal muscles expand the rib cage. This increases thoracic volume and creates negative pressure, drawing air through the nose or mouth, past the pharynx and larynx, and down the trachea into the lungs.
2. Gas Exchange
Air travels through the bronchi and bronchioles to tiny air sacs called alveoli. Surrounded by capillaries, the alveoli allow oxygen to diffuse into the bloodstream, where hemoglobin carries it throughout the body. At the same time, carbon dioxide moves from the blood into the alveoli to be exhaled.
3. Exhalation
The diaphragm and intercostal muscles relax, reducing thoracic volume and pushing air out through the same pathway in reverse.
Chimpanzees typically breathe 15 to 30 times per minute—slightly faster than humans—and can voluntarily adjust their breathing during exertion or while holding their breath.