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Since winter in Argentina is from July to October why would a Tegu living indoors in S. FL (or any where for that matter) want to start hibernating around Oct.-Nov. even if their temps and feeding schedules are kept the same all year round. I believe Tegus have been bread here in the US for less then 10 years. Is this long enough for their instinctive seasonal clock to reset to N. America's seasons? Or do they sense the climate change out side even though they are kept inside. Wondering if anyone had any thoughts or ideas. Thought this might make for some interesting discussion.

You know, tc5000, I'm rather embarassed, as this IS my expertise and I'm afraid I can't really answer your questions with certainty. I am currently researching reptilian hibernation, using T.merianae as a model (mainly because my telemetry implants are so big that T.merianae is the largest reptile which I know of that hibernates AND that I could get a ready supply of and access to "field" research facilities). However, there is one thing that may somewhat answer your question semi-directly. Amongst hibernators, there are two main categories - facultative and obligative. Obligative hibernators are those animals that essentially have an internal clock that tells them it's time to hibernate, irregardless of ambient conditions. It's almost impossible to force such an animal into hibernation, but on the other hand, it will go into hibernation reliably on it's own when the time is right. The golden mantled ground squirrel (Spermophilus lateralis I think) is such a critter.
The other class, facultative hibernators, are those that appear to rely on zeitgeibers (external stimuli cues) to tell them it's time to hibernate. Without those zeitgeibers, they will continue on merrily being active. Tupinambis merianae is a facultative hibernator. It remains unclear what zeitgeibers T.merianae is cluing in on to determine time to enter hibernation. They certainly utilize light, but a change in light alone will not induce hibernation behaviour. They also cue in on temperature, however again, a change in temperature alone will not induce hibernation. It would appear that there is a complex interaction between these cues that T.merianae utilizes to determine hibernation time. Plus, it hasn't been ruled out that there could be other factors at play as well - drop in humidity, overall change in average atmospheric pressure, etc. So, yes, I would believe it would not take long for a South American Tupinambis spp. to acclimate to North American seasonal cycles.
BUT, and here's the kicker that really is confounding, in the wild, T.merianae show preparation for hibernation behaviour (reduction in appetite, fasting, nest building, etc.) long before ambient conditions such as temperature, humidity, photoperiod, resource availability, etc., fall outside the parameters of typical active season measurements. The only cue then that I think they could be using (but I'm very open to suggestions) isn't photoperiod itself, but the decreasing trend in photoperiod. I haven't tested this idea yet, but there's a certain potential flaw to that theory. In the subtropics, there really isn't that much change in photoperiod at all.

It may be not so much the decrease in photoperiod as the lack of increase, if you understand what I'm saying. There is a whole continuum of photoperiod changes that is constantly changing. Plus, there are many factors associated with the change of photoperiod that we humans do not trigger on, and therefore may not even be aware of, but that other creatures may be aware of and be affected by. That is essentually one of the problems in studying any animal behavior. We as an 'animal' have been tampering with our environment to suit our comfort for some time. Any subtle triggers that the human animal may at one time have had are not used anymore, and therefore probably not a factor in our response to the environment. It becomes, therefore, more difficult to judge what may be a trigger for other animals, as we have largely lost our own innate triggering on the natural environment. While I am not a herp researcher, as a horse owner and occasional breeder, I can sure tell you that a horse growing a winter coat is not temperature specific, and probably not entirely photoperiod specific, although a lot of prople will leave lights on in an effort to retard the growth of a heavy winter coat in show horses. There even appears to be some variation in horses' winter hair growth by breed, and even by bloodline.

Basically, it comes down to the fact that animals seem to know what time of day, and what time of year, it is no matter what we humans do to try to fool them. Fascinating.

Leslie

I have to agree with Leslie:
"Basically, it comes down to the fact that animals seem to know what time of day, and what time of year, it is no matter what we humans do to try to fool them. Fascinating."

I am not a researcher either but this was my theory when I posed the question and I believe this would agree whit things I have read from Frank R on the Monitor forum. FR is no scientist but probably one of the most knowledgeable breeders I have come across.

tupinambis is no longer able to post on kingsnake. He assumes that he was probably banned, no warning or reasons given.

If you have further questions for him, he has joined theTegu.com

Rick
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