Some predators will test whether an object is edible by gently mouthing it. If they find it inedible or not to their liking they will ignore it. Dragons prefer to test whether an object is edible by gently setting it on fire, which -although highly successful for determining edibility- is very destructive to the object.
The existence of gnomes is a hotly debated topic in scientific circles. All possible concrete evidence of their existence is believed by most to be lost to the ancient past. I believe that frequently reported aspects of dragon behaviour may prove that they did in fact exist and what’s more, I am almost certain that dragons played a part in their disappearance. Why would I think this? Firstly Gnomes would have been rich in protein, and being a peace loving people would have been easy pickings for a hungry dragon, or even a not so hungry dragon just wanting a snack. Therefore it is highly probable that Gnomes formed an important part of the ancient dragons food chain. Secondly, the common garden Gnome is the most popular modern depiction of the Gnome, they are small and generally made of concrete. People in known dragon hot-spots have frequently reported stolen, smashed and even burned garden ornaments which leads me to believe that these little figures are still etched in collective dragon memory as a food item. This, I believe, lends strong evidence to the possible existence of the Gnome people and an explanation for their extinction; Being small and tasty and completely unable to fend off hungry dragons.
Despite common belief dragons despise butterflies. I am not quite sure why, though I have a theory.
Butterflies are beautiful and colourful, they are the treasures of the animal kingdom. However they are also alive, making them difficult to catch and they have a general unwillingness to lie down and become a permanent fixture in a pile of treasure. Should they be caught they also disintegrate in heat and with rough handling.
Thus Butterflies are an unending source of frustration to dragons. They covet butterflies yet ultimately destroy the treasure they long to poses. It is probably then, in their frustration that they burn to dust the entire field of flowers the butterfly once called home and return to their cave to curl up on some less rebellious treasures.