Are there any official sources of bioinformatics (for lack of better word; though mapping the elven genome might be a useful way to figure out their longevity…hmm…) for the races of Dungeons & Dragons? (Any edition) – besides the obvious height and weight tables in the Player's Handbook.
Specifically, I'm looking for the core temperature of warm blooded races like dwarves, humans, elves. I'm also trying to figure out if Yuan-Ti pure blood spies can be identified via a simple thermometer test, assuming their snake features are hidden or minimal/not in a visible part of the body. (I have a character who looks human for all intents and purposes, but her abdomen is scaly, making her an ideal infiltrator.)
This is for a new custom setting where the snake people have essentially taken over the world. The warm blooded races are paranoid after years of being infiltrated and enslaved. And so I'm looking for the equivalent of the blood test in the movie The Thing with Kurt Russell.
Since this is a post-apocalyptic fantasy setting, with technology items pilfered from other planes, I'm also interested in a little bit more of the science and biology of the races. If in doubt, I'll just make it up. Just figured I'd ask around first. Thanks!
Best Answer
Humanoids are approximately as warm as real-world humans; yuan-ti are somewhat ambiguous.
Wilderness Survival Guide (1986), p. 74, discusses the use of Infravision (the ability to see into the infrared spectrum in order to see in the dark) regarding humanoids and other creatures.
Humans are stated to have a body temperature of approximately 98 degrees (Fahrenheit, it must be assumed), which is equivalent to the real-world human typical body temperature of 98.6°F.
However:
What this means is that mammalian humanoids are most likely to have body temperature similar to humans, though I do not believe there is any precise measurement for non-humans in the lore; while reptilian creatures will often have lower body temperatures. Thus, using a thermometer to detect yuan-ti by body temperature is plausible if they are reptilian rather than mammals.
Yuan-ti are described as reptiles, though with purebloods it is sometimes ambigious.
In this case, the question comes down to whether yuan-ti purebloods are warm-blooded like mammals, or cold-blooded like reptiles. This isn't clearly specified in the lore.
Dragon Magazine #305, Venom and Coil: The Secret Life of the Yuan-ti states that the yuan-ti are essentially reptilian:
And:
Yuan-ti purebloods are described in this article as looking essentially human, but possessing serpentine features upon closer inspection. Volo's Guide to Monsters describes purebloods as the least snakelike of the yuan-ti, with yuan-ti sometimes laying eggs (as reptiles), but sometimes giving live birth (as mammals).
Summary