Deepest Dive Under Antarctica Reveals a Vibrant World (2017)
nationalgeographic.com
nationalgeographic.com
Instead of abundant crabs and other crustaceans and mollusks, "Under Antarctica" the most abundant big animals on the bottom are echinoderms, sea spiders and nemertean worms.
The disappearance of these predators has allowed other animal groups to flourish, while in other places those groups are restricted to higher depths, where such predators are also absent.
Are you sure that's it? Sea water doesn't get any colder than a couple degrees below 0C, so the whole antarctic and arctic seas are all very similar temperatures no matter what part or what depth you're at. The crabs and fish have antifreeze protein in their blood too.
It's the same insanity that allows industrial fishing fleets to drag kilometers-long nets through the sea scooping up megatons of bycatch -- although, this time we are likely to obliterate seabed ecosystems before anyone even has a chance to see them.
Some brilliant reads on these and surrounding topics:
https://www.harpercollins.com/products/the-deepest-map-laura...
It is Atlantis under the ice, after all.