This article was originally published January 11, 2016 by Rebecca Hofland over at the PLOS EveryONE blog, a member of the PLOS Blogs Network. We bring you a snippet of the article here, and encourage you to follow over to the original post to read it in its entirety.
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 their body temperature.
The green iguana transfers heat from its head to its body and vice versa using known sites of thermal exchange – or areas where warmer or cooler blood is delivered to regulate temperature in some reptiles – in the blood vessels, located in their mouth, nose, and eyes. They do this without an advanced rete mirabile, or complex network of blood vessels, that regulates temperature in some vertebrates. The basic circulatory system seen in green iguanas led scientists to suspect that it may be similar to that used by dinosaurs. This is because extinct dinosaurs are also thought to have highly vascularized sites, which suggest that they were able to thermoregulate in a way that may be similar to the iguana.
The authors of a recently published PLOS ONE study mapped the circulatory system of green iguanas with the goal of identifying which blood vessels may contribute to heat transfer within the blood, as well as create a comprehensive map of the circulatory system for future reference….
Citation: Porter WR, Witmer LM (2015) Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange. PLoS ONE 10(10): e0139215. doi:10.1371/journal.pone.0139215