Quote Originally Posted by Argentra View Post


Oh, and just one minor thing, Ringo: we biologists no longer say 'warm blooded' and 'cold blooded'... now it's endothermic and exothermic.
To be more accurate, cold-blooded is called ectothermic (exothermic is used in thermochemistry, not thermophysiology for some reason). Sometimes "cold-blooded" critters are called "poikilotherms."

If you want to be real technical, poikilothermic doesn't mean the same thing exact thing as ectothermic. "Ecto" means to use the external means to control you inside body temperature. "Poikilo" means to have your internal temperature the same as the ambient temperature (and vary as such).

So an animal could technically be ectothermic and not poikilothermic. For example, a large cold-blooded critters like a great white shark is ecothermic, but when it dives to great depths it is much warmer than the outside environment. Great whites have low surface area to volume ratios which allow them to keep their core body temperatures higher than their environments for great periods of time.

The whole subject of thermophysiology is much more complicated than warm vs cold blood. Some animals display different thermoregualtion depending on the time of day, year, or part of their life cycle.

Quote Originally Posted by Ringo View Post

As for cold blooded species, the majority of their body temperature comes not from metabolic activity but from the environment they live in. This is why they can tolerate such vast ranges in temperature compared to warm blooded species. So to get to the point, it is really a matter of at what temperature do ball pythons function the best. As long as there is a temperature gradient within their range then just let them control their own body temp.

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You seem to be confusing the ideas of body temperature and envirnomental temperature. I think you probably understand the difference but you wrote in a confusing way above.

For ectothermic animals like snakes-they can tolerate changes in their body temperature--They sort of have to since their body temperature is dependent upon the fluctuating environmental temperatures! This, however, doesn't mean they can tolerate just any environmental temperature or just any temperature gradient for long periods of time. Unlike endothermic animals they cant burn brown fat to change the body temperature. Basically, they don't use metabolic means to generate heat for their bodies. They do however have metabolic adjustments for their fluctuating body temperatures. They can tolerate some changing body temperatures by switching between different forms of enzymes. Each enzyme form, or isozyme, is optimized for a different body temperature range. So they can survive at a lower temp. gradient by adjusting the relative levels of different isozymes. Still the types of different isozymes they have are limited. If they don't have isozymes that function in that range then they wont survive long at those temperatures.


These are helpful links

http://en.wikipedia.org/wiki/Warm-blooded

http://en.wikipedia.org/wiki/Cold-blooded

http://coolcosmos.ipac.caltech.edu/i.../coldwarm.html