Steven

I would suggest reading some posts out here about acclimating new animals. You should try not to handle them for a few weeks or longer if needed. Letting them loose in the house is NOT a good idea. These guys can move fast and can also wedge themselves into the smallest places.

Frocto,

If I said that a uromastyx optimal body temperature is 105F, then I misspoke.

It is best to leave her alone for 2-4 weeks so she can get acclimated.

Mine don’t bite, but they sure as heck lick my hands/fingers when I scratch their heads/chins!

It certainly does not appear to be body temperature as some people speculate. I have monitored indoor body temperatures against outdoor body temperatures and I do not see any evidence of body temperature being the cause. I will admit that optimal body temperature will make a uromastyx more active and a little more skittish but I have not noticed aggressive behavior because of an optimal (my guess at) body temperature.

I could speculate…
Very few of us are able to provide a level of 250+ uW/cm2 for our uromastyx which is a typical summer uvb level here in Ohio. I am thinking that this higher level of uvb might have something to do with the change in behavior. I tend to see less aggression with lower levels (generally 150 and below) of natural uvb.
One could also speculate that being outdoors could possibility trigger that natural instinct to fight and escape. Who knows, could be a combination of the two of these or something entirely different.

I am not certain if the manufacturing of d3 is directly responsible for the aggression and hyperactivity seen with exposure to natural sunlight. The change in behavior is almost immediate with some animals so I am not convinced that d3 synthesis is the primary cause. I have not seen any research on how quickly a reptile synthesizes d3 when exposed to natural sunlight but I do know that elderly people are less efficient at producing d3 as their skin ages. How quickly d3 is manufactured with a scaled animal or how the presence of d3 in the body affects behavior, I cannot say.

A reptile synthesizes d3 when exposed to artificial uvb light so even though these levels tend to much lower, the production of d3 is still likely taking place. Again, I am not certain (numerous opinions out there floating around) what specific levels are needed for this production and how this level differs between species.

If d3 is the primary cause for this change in behavior, I would think that we would see some sort of similar behavior with those animals that are supplied higher levels of artificial uvb. I do not see any behavioral (aggressive or hyper) pattern with differences in indoor uvb levels (even with my highest levels) but have personally noticed better eating habits with those which have the higher uvb levels in my enclosures.

"If d3 is the primary cause for this change in behavior, I would think that we would see some sort of similar behavior with those animals that are supplied higher levels of artificial uvb. I do not see any behavioral (aggressive or hyper) pattern with differences in indoor uvb levels (even with my highest levels) but have personally noticed better eating habits with those which have the higher uvb levels in my enclosures."

UPDATE:
Now that I am using artificial uvb bulbs producing over 200 microwatts (uwcm2) of uvb, I HAVE seen aggressive behavior in some of my uromastyx. The aggression seems to subside after several days of repeated exposure.

My opinion continues to side more with this behavior being more psychological than d3 related. D3 is still synthesized (as far as studies have proved with other reptiles) with the lower levels of uvb so if the cause were primarily due to d3, I think we would see ‘some’ aggression with the lower levels.