I know that chicks get their heat from mama's feathers above them and reptiles get their heat from lying on rocks warmed by the sun, but is there any obvious reason why you shouldn't or couldn't put a reptile heat mat under half of your brooder floor instead of having a bright light shining on them from above? Not something I'm thinking of doing, just wondering out loud, because I saw them sitting on the shelf when I bought my heat lamp from the reptile section of my local pet shop...