I don’t think I’d go so far as to say that the idea of zombies being “cold” made no sense to me, and that’s why I years ago decided the zeds of our particular settings wouldn’t go that route, at least so long as they were in periods of activity. It perhaps makes more sense, but I’m not precisely aiming for scientific acumen or ironclad logic on explaining how my dead people walk. That said, I have notes. This is not something I made up recently, it’s pretty much been there since the start and just hasn’t really come up in the story. Most of the time in this genre I think it’s a mistake to get too lost in the details of why your zombies work. As far as the story is concerned, keep to the important bits like, well… the biting. But then again it makes sense, doesn’t it? As a (layman) physics concept, motion requires expenditure of energy and energy expenditure gives off some measure of waste heat. That’s just basic thermodynamics right there… and now I’m starting to sound like Uncle Chuck but hopefully am not as off base as he sometimes can be. So I have my logic structure of why and how my zombies work but there’s every chance that were I to ever reveal every last detail of that the scientists in the audience could tear me apart as readily as any undead horde. Would they be right to do that? I suppose that would depend on how seriously I’m presenting things, and I like to think I’ve gotten across the gist that Zombie Ranch is not meant as some actual post-apoc survival guide for battling zombies. To paraphrase The Princess Bride: zombies are fiction, highness. Anyone who tries to tell you different is selling something.