Running body temperature of tigers? Cold temps?

[king]

Hey everyone, hope we're all doing well!

I have a question regarding tiger's temperature. I understand they require relatively low temperatures, and can be seen in and around snow at times.
What is the tiger salamander's resting body temperature? What part of it's bodily function makes it capable of withstanding such cold temperatures, unlike a Uromastyx lizard for example, a reptile, who would not last very long in the same conditions?

Thanks so much!

 

[peter5930]

Tiger salamanders are ectotherms, which means they don't have a fixed resting body temperature, and their body temperature is dependent on the temperature of their environment.

Living organisms use biological catalysts called enzymes, and these enzymes only work within certain temperature ranges. If the temperature is too low, the enzyme won't be effective in catalysing chemical reactions and if the temperature is too high, the enzyme gets damaged and stops working. Different animals have evolved different sets of enzymes to suit different temperature ranges, depending on what temperatures they're naturally exposed to. In a hot desert, a tiger salamander's enzymes would quickly be damaged by the heat and stop working, since they're not adapted for high temperatures, but will work effectively at low temperatures when an Uromastyx lizard's enzymes may be too sluggish to keep it alive and healthy for long periods.

Organisms also have adaptations such as anti-freeze, cold-shock proteins and heat-shock proteins that help them to survive temperature extremes, just as they have UV-absorbing pigments to protect them from UV damage (if they're naturally exposed to UV light) and proteins which help other proteins to fold correctly if they live at great depths in the ocean where the pressure is very high.

 

[king]

Peter, Thank you so much for your detailed answer! I learned something new

 

[Vesp]

This is kind of related, and not worthy of a new thread -- But at what temperature do tiger salamanders stop crawling around in the wild? At what point do they go off and hide and wait for the winter to come?

For Northern Utah weather, is it too late (Oct 11th) to find some crawling about?