Board Thread:Speculation House/@comment-4010415-20131006060026/@comment-7472785-20131012080241

Dinosaurs aren't descendants of reptiles for the simple reason that 'reptilia' is a classification of naming (implemented long after their extinction) which describes a class of species of which (most) dinosaurs are a part, as are today's remnants as turtles, crocodiles, snake, lizards etc.

The simplest definition is:  A reptile is any tetrapod that can lay eggs on land, that is neither a  mammal nor a bird.

Notably that does not include being cold blooded!