The European Green Lizard, Lacerta viridis, shows off a blue head while catching some rays. Lizards and other so-called "cold-blooded"
animals have complex biochemistry: sometimes they have 4 to 10 different enzyme systems where humans would use only 1. Cold-blooded critters need this complexity so that their bodies function no matter what the weather forecast brings. To learn more about how that fantastic genetic diversity is at risk from global climate change along with more gorgeous photos of these climate-dependent ectotherms, click the slideshow.