What's warming the cold-blooded iguana?

Now that dinosaurs no longer roam the Earth, scientists use modern animals to understand how their ancient ancestors reproduced, walked, and even how they regulated their body temperature. While researchers continue to debate about how dinosaurs regulated their body temperature, some are looking to reptiles as a potential model, because they are able to gain and lose heat rapidly and precisely by using their circulatory system to not only transport blood through their body, but also to control t