lpetrich
Contributor
I first discuss Boiling frog, that if one heats a frog slowly, it will become accustomed to the heat and not jump away. That was more-or-less hinted at by some work in the late nineteenth century, but recent researchers into amphibian temperature tolerance have found that to be just plain false. When a frog is heated enough, it will try to jump away, even if it was heated very slowly. In fact, heating the animals slowly is a good way to get a good number for temperature tolerance.
A better example of what this supposedly illustrates is removing a bandage. It's often less painful to remove them slowly than to remove them quickly. Or else being jabbed by a needle.
I'll now turn to the main subject.
Since every known organism needs liquid water to metabolize and grow and reproduce, it would seem that the lower limit of temperature is set by the freezing point of water, 0 C. Indeed, freezing is deadly to many organisms. Ice crystals forming inside of cells will damage them beyond viability. But many organisms have ways around that problem.
One of them is antifreeze. Many organisms, including various fish, insects, plants, fungi, and bacteria, make antifreeze proteins. Living organisms need antifreeze to survive in the cold describes some research into these proteins. Lowest temperature for life discovered noting A Low Temperature Limit for Life on Earth proposes -20 C as a lower limit for organisms metabolizing. But antifreezes have an additional benefit. They can keep water from crystallizing as it freezes, making it an amorphous, glassy solid, and keeping cell structures intact. Thus, organisms can go into suspended animation rather than dying.
Suspended animation (cryptobiosis) can also be done by drying (anhydrobiosis), and that also enables survival at low temperatures.
A better example of what this supposedly illustrates is removing a bandage. It's often less painful to remove them slowly than to remove them quickly. Or else being jabbed by a needle.
I'll now turn to the main subject.
Since every known organism needs liquid water to metabolize and grow and reproduce, it would seem that the lower limit of temperature is set by the freezing point of water, 0 C. Indeed, freezing is deadly to many organisms. Ice crystals forming inside of cells will damage them beyond viability. But many organisms have ways around that problem.
One of them is antifreeze. Many organisms, including various fish, insects, plants, fungi, and bacteria, make antifreeze proteins. Living organisms need antifreeze to survive in the cold describes some research into these proteins. Lowest temperature for life discovered noting A Low Temperature Limit for Life on Earth proposes -20 C as a lower limit for organisms metabolizing. But antifreezes have an additional benefit. They can keep water from crystallizing as it freezes, making it an amorphous, glassy solid, and keeping cell structures intact. Thus, organisms can go into suspended animation rather than dying.
Suspended animation (cryptobiosis) can also be done by drying (anhydrobiosis), and that also enables survival at low temperatures.