Extreme extremophiles: deep under Antarctic ice (Introduction)

by David Turell , Friday, February 26, 2021, 04:40 (1368 days ago) @ David Turell

More on these sessile creatures:

https://mail.yahoo.com/d/folders/1/messages/AN1AQ5wCgIg6YDhnwQ6C2OhuQeY?.intl=us&.p...

"A new study details the discovery of sessile organisms found deep below Antarctica's Filchner-Ronne Ice Shelf. The organisms were anchored to a boulder 900 meters beneath the ice, living a cold, dark existence miles away from the open ocean. "This discovery is one of those fortunate accidents that pushes ideas in a different direction and shows us that Antarctic marine life is incredibly special and amazingly adapted to a frozen world," Dr Huw Griffiths, the study's lead author and a biogeographer of the British Antarctic Survey, said in a press release. Sessile creatures are defined by their inability to move freely. They live their lives anchored to a substrate—in this case, the aforementioned boulder. Common sessile animals found in coastal tide pools include mussels, barnacles, and sea anemones, yet none of these were present beneath the Antarctic shelf. Instead, the researchers discovered a stalked sponge, roughly a dozen non-stalked sponges, and 22 unidentifiable stalked organisms.

"Sessile organisms depend on their food to be delivered to them. That's why they are so bountiful in tide pools; tides and currents are the DoorDash of the ocean world. It's also why the researchers found the sponge's Antarctic lodgings so astounding. Because they live 1,500 kilometers upstream from the nearest source of photosynthesis, it's unknown how a food supply reaches these sponges or whether they generate nutrients from some other means, such as glacial melt or carnivorous noshing."

Comment: These immobile organisms are surviving. The point I am making is life always survives, so survival is not an issue that drives evolution. Life designed peremptorily to survive. Opposite to the Darwin approach. Extremophiles make the concept clear.