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Why don’t deep sea creatures get crushed?

René Wilbrandt
February 28, 2024

The deeper you dive, the higher the water pressure — so why don’t deep-sea creatures get crushed?


This week's Tomorrow Today viewer's question comes from Yu Pang Yeow in Hong Kong. You can also submit a question to us –just ask!

The Earth’s oceans are, on average, 4,000 meters deep — anything deeper than 200 meters is considered deep sea. In the 19th century, scientists began to chart the depths of the oceans. One of the pioneers of deep-sea research was Edward Forbes and, according to his theory, life couldn't survive in waters deeper than 500 meters.

Today, we know that the deep sea is home to a variety of marine life, even though deep-sea conditions seem pretty inhospitable: the water temperature is always cold, there’s no light, and the pressure is immense. The deeper you go, the greater the water pressure. At 10,000 meters deep, there’s one ton of pressure per square centimeter. And yet sea creatures don’t get crushed — why?

Diving deep thanks to protein stabilizer

Most deep-sea creatures don’t have a swim bladder or other hollow organs. Deep-sea creatures also have higher inner pressure and so would never survive close to the surface. Another trick up their sleeve: Trimethylamine oxide, or TMAO for short. This molecule stabilizes the proteins within the cells so that they don’t lose their shape under high pressure. The higher the concentration of TMAO, the deeper the creature can go.

The human body could never survive such pressure. But with diving bells, humans have gone all the way down to 10,000 meters. The world record for the deepest dive without a protective capsule was just 333 meters — and it took the diver 15 hours to equalize the pressure on his ascent!

Tomorrow Today – The Science Magazine