I found an article (sorry – the link is eluding me) about the possibility of hot-blooded dinosaurs.  While the study didn’t make any firm statements, the jist of it is that some dinosaurs may have used thermal inertia to keep their body temperature up, just as alligators, Komodo dragons, and Galapagos tortoises do today.  This would be true of the largest dinosaurs, and would mean that they could easily run a standard temp. of over 110 degrees F.   

This came as a great relief to me.  My most developed world has reptiles of the warm-blooded variety mixed in with their cold-blooded cousins.  I was concerned that this would stretch reader credibility, but now I have an easy way to make that sound plausable, and can laugh in the face of any reviewer that calls my world a fantasy.

But where would dragons fit into this?

Just take the idea of a hot-blooded dino one step further.  What I’m picturing is a bunch of big dino-reptiles sitting around after their Thanksgiving feast feeling hot.  They’re big, they’re full, and their temperature is headed higher than the rain-forest tree tops.  Then along comes a little scuttle-butt dino who bites a big fella on the tail and- Whoomp!

The big boys temper soars up to match his body heat.

Now the course of evolution has to make a quick choice.  Big daddy can grab the pesty critter and gulp him down, but he’s already full.  Besides, eating=growth=a hotter temperature, which will only perpetuate the problem.  So maybe madame evolution takes an alternate route.

The dino-monster turns his head and blows a mass of heat at the annoying little bugger.  The pest goes up in flames, the big dino blows off steam, and voila! You have a fire-breathing dragon.