Cold weather creature question

[Zergling]

How do cold weather creatures (Arctic fish, tundra insects, etc.), keep their metabolism going at the low temperatures they will likely have?

This just occurred to me recently. I have heard about how hypothermia in humans will really slow most body processes down (possibly because of hormones or nerve signals, but still slower.), how chemical reactions, diffusion, etc. sometimes change speeds quite a lot with temperature, and it also seems that smaller creatures in cold water or cold air with no fur and such will pretty easily get cold enough to cause things to slow down.

 

[Usehername]

How do cold weather creatures (Arctic fish, tundra insects, etc.), keep their metabolism going at the low temperatures they will likely have?

This just occurred to me recently. I have heard about how hypothermia in humans will really slow most body processes down (possibly because of hormones or nerve signals, but still slower.), how chemical reactions, diffusion, etc. sometimes change speeds quite a lot with temperature, and it also seems that smaller creatures in cold water or cold air with no fur and such will pretty easily get cold enough to cause things to slow down.

they slow down the heart rate a ton, that's really all that I know.

 

[Randomnity]

-because fish are cold-blooded, their body temperature in cold water is very low, so their metabolism is slowed
-most of them have molecular specializations on the cellular level that allow them to survive without molecular damage from the cold
-all the chemical reactions that occur are much, much slower, although a lot of species have evolved specialized enzymes which help compensate for the effect of the cold
-a lot of arctic fish barely eat anything, and have to wait a long time for it to digest, but they have low energy needs so it balances out.
-they also move more slowly, but since predator/prey fish would also be moving slowly, it wouldn't be that huge of a disadvantage
-basically everything in their body happens in slow motion, maybe with some exceptions I'm unaware of

It's much harder for warm blooded creatures, who have to maintain a constant body temperature that's far higher than the environment in order to survive. Especially on land, which is far colder than the water.

 

[sundowning]

This reminds me of a type of worm they found living in glaciers that - as the story goes - actually 'melts' if removed to a warmer environment.

It's interesting because one of the things scientists are look at when talking about the earliest occurence of life (or extraterrestrial life) are these extreme environments where life amazingly exists.

(...that doesn't have much to do with complex organisms or the OP for that matter, but I thought I'd just throw it out there anyway.)

 

[Ivy]

I was thinking of the creatures that live near the undersea vents, where the temperature and pressure is so high. I think I remember reading that they have always died when brought to areas of "normal" temp/pressure.