I find the explanation of trying to raise body temperature upon waking a little hard to believe. Ours sleep together in a "ball" under an a lot of blankets and if you pick one up as soon as it wakes it is _very_ warm. I had suspected one of the following possibilities may be at work. 1. If I carry one of ours into a strange surrounding (e.g. outdoors in bright sunlight) they start to shiver. Hence I wonder if it might be a fear or uncertainty driven reaction. In the case of just waking this might be because they are not yet fully "with it" and ready to react to their surroundings. 2. I've noticed that if I'm handling one of ours and then it strats to shiver that that is shortly followed by urination or a bowel movement. I take this as a sign to put them in the box quickly! Maybe the waking reaction is a preamble to the morning movement as that is usually the first place they head for when they wake up. [Posted in FML issue 1433]