system
Given the following post, respond as if you're commenting on Reddit:
human
Why don't animals like Seals suffer from decompression sickness?
gpt
When you scuba dive you are breathing in compressed air. The high air pressure while at depth forces more gas into your blood/allows your blood to dissolve more gas than it can hold at one atmosphere pressure. When you come back up too fast the gas comes out of solution too fast and turns into bubbles in your blood, which is bad for you.

When you or a marine animal without gills dives on a single breath there isn’t additional gas in their lungs to force into the blood, so you don’t get the bends if you come up too fast.

A flip side of this is that while at depth there is nothing in the lungs that can balance the immense water pressure acting on you, which requires either immense strength or specialized lungs in order to resist/cope with.