Natures wonders: the deepest fish (Introduction)

by David Turell , Monday, September 11, 2023, 21:33 (437 days ago) @ David Turell

At crushing pressures:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGtwzrhTJGnKmwgLwDTWmQLRBKr

"The Deepest Fish

"Scientists exploring a marine trench near Japan were shocked to find a fish 8,336 meters (about five miles) below the surface. The tadpole-shaped, translucent snailfish is adapted to live in this particular trench, as is each of the roughly 400 other known snailfish species–they stay in their trenches and can never move to another.

"How this is possible: Fish can tolerate high pressures at extreme depths because of cellular compounds called osmolytes. Osmolyte concentrations increase at greater depths to ensure that fish cells can withstand bone-crushing pressures. These compounds reach their maximum concentration at around 8,400 meters, so that’s the hypothetical limit of fish physiology. Temperature is also key: osmolytes are less effective at low temperatures. The bottom of the trench where this fish was discovered had low temperatures of about 1.7 degrees Celsius.

"What the experts say: It’s pretty impressive that these fish can survive 800 times the surface water pressure. “At that depth everything from gas exchange for breathing to nearly every physiological function seems impossible,” says Alan Jamieson, a marine scientist at the University of Western Australia. “I can barely swim to the bottom of a swimming pool without my ears popping.'”

Comment: another form of extremophile. How did it happen? If it is very uncomfortable why try to go lower? Therefore, not step by step, but design fits.