system
Given the following post, respond as if you're commenting on Reddit:
human
What happens to aquatic life when a lake freezes over? Do the animals and plants somehow hibernate, or do they find a way to live under to ice? Where would they get oxygen?
gpt
It really depends on the organism in question. Many fish remain isothermic with the water, and do regular fish things, others will go into a semi-restful state where they are sluggish and barely move to conserve energy. There are frogs that will bury themselves in the mud and essentially hibernate through the winter, and even some frogs that allow themselves to become fully frozen in ice until the spring thaw. 

Arctic fish have adapted to the cold and contain antifreeze compounds in their bloodstream, while Arctic aquatic mammals have thick layers of blubber to provide insulation in the cold waters.