system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What stops whales from dying of dehydration through osmosis when they gulp in multiple gallons of salt water at a time when they catch fish?
gpt
Baleen whales (filter feeders) don't swallow all the water they take into their mouth. They push it back out through their comb-teeth, and then swallow just the stuff they want to eat and a smaller amount of water. But, they do end up swallowing a lot more salt water than you could - they have big, super-efficient kidneys and excrete a lot of salt.