Tempreature can be fooled quite easily. Unfortunately I couldn't find the link to an article I read >6 months ago, but an (I think Italian) uni prof did some gelatin finger experiments to spoof finger print scanners. He used a couple of different methods to get the print and made a gelatin 'finger' with the extracted print on it. For the ones that required tempreature he simply left the fake fingers in warm water before using them on the scanners. From memory it was approximately an 70-80% success rate. Quite surprising really.

Pulse and the right type and amount of moisture is a significantly bigger challenge though.