How can penguins hold their breath so much longer than humans?

Question

They have smaller lungs and everything. I asked this question earlier, but I got two answers.
1. Are you sure they can?
2. [Link to a website about how far they can dive/how long they can hold their breath.]

According to that website, they can dive some 180 feet and hold their breaths for 18 minutes, which is the record held by the emperor penguin. Either way, I still don't know how they can do it.

Answer 1

Evolution. While their lungs are certainly smaller their lung volume to body volume might not be. But They would have to have small lungs to dive so deep. Large lungs would give them too much flotation. They probably have much more hemoglobin proportionally in their blood. It is the hemoglobin which stores the oxygen.

They are probably much better at anaerobic metabolism than we are. So if they can function using metabolic pathways which do not require oxygen they could naturally last longer.

Remember that humans use 20 percent of their blood supply to oxygenate our oversize brain.

Answer 2

When you sleep on your arm it may become numb from lack of oxygen but will survive when circulation is restored. The human brain at normal body temperature can go without adequate oxygen for only short periods before death and non-reversible damage occurs. Penguins have smaller less complex brains and perhaps cooler blood slowing metabolism in their brains. Children who fall through ice and drown have been revived long after oxygen deprivation would end an adult's life.

Answer 3

Their bodies absorb oxygen at a much slower rate.

Answer 4

they keep little scuba tanks under the ice

Answer 5

because they are not human