Marine mammals use 75% of their total lung capacity when breathing, while humans only need to use 10 to 15%.
To increase the amount of oxygen in their lungs compared to the amount of carbon dioxide, marine mammals intentionally hyperventilate.
Sea otters have lungs that are three times the average size for animals with similar body mass.
Whales and dolphins are voluntary breathers, meaning they have to remember to breath. This is very different from land mammals that are capable of automatically breathing as involuntary breathers.
Bottlennose dolphins breath in and out within a third of a second.
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