system
Given the following post, respond as if you're commenting on Reddit:
human
Why do whales die when they're beached too long? What is it that kills them?

I have always wondered this. 

**Edit:** Thank you for your responses, everyone!
gpt
It's not dehydration or starvation, which would take a long time, but suffocation. Whales are normally supported on all sides by water, which means that they don't have to support their own weight against gravity. When they are beached, the weight of the parts of their bodies that are above their lungs is pushing down on their lungs. They will have to work incredibly hard to expand their lungs to breathe. Eventually they don't have enough energy to expand the chest cavity to draw in air, and they suffocate. This is the same mechanism by which people would have died through crucifixion. Holding your body up by your arms forces you to work hard to breathe and eventually you can't do it any more and you suffocate.