Deep sea life, just HOW do they withstand the water pressure???

Aleister

...and I have never understood, after a long time of admiring these animals, just how in the deep blue sea they not only don't get crushed by the amount of weight of water bearing down on them but how can they be so delicate looking while surviving? Man needs massive metal inventions to go down into these depths, and even then, if there was the least bit of pressure loss, the enclosures they go down in would crush like a tin can.

As these critters live in the ocean and don't breath gases like we do, it's not an issue for them.

The whole crushing thing is related to our unfortunate habit of liking air to breathe.

Now, as you go up in pressure to ridiculous extremes, like where these live, you actually get into the levels of pressure where you're changing the shapes of molecules. So you get into situations where some enzymes don't work, or don't work well enough, because they're deformed slightly by the pressure and no longer "fit". So deep sea life evolved slightly different enzymes and proteins to fix that. There is also an issue with solubility of some chemicals you'd want, and also that some substances are more toxic at pressure and you need to adapt for that too.

reply to post by Bedlam


So...in the evolutionary timeline at some point something diverged into upper-sea level and deep-sea level life forms. I wonder how much is left in common, the percentage of DNA overlap. I think the theory/thinkng now is that everybody evolved from something like a sea anemone.

reply to post by Aleister


Perhaps it would help to imagine a balloon in deep water . . . not sealed and full of air--but say torn . . . a loose balloon skin . . . the water outside the balloon is the same pressure as the water inside the torn balloon or the balloon with a hole in it.

The balloon's thin skin would be quite moveable within the deep water even though it's very thin and not all that strong--simply because of the equal pressure within as without.