Most lizards have red blood, just like humans and other mammals. However, some species of lizards, particularly those found in New Guinea, have lime green blood. This unusual color is due to a high concentration of the green bile pigment biliverdin in their blood. Biliverdin is a byproduct of the breakdown of red blood cells, and in most animals, it is quickly removed from the bloodstream. However, in these green-blooded lizards, biliverdin accumulates, giving their blood its distinctive color. This green coloration extends to their muscles, bones, tongue, and mucosal tissues.
It's important to note that while these lizards have green blood, their blood still carries oxygen, just like in other animals. The green color doesn't affect their ability to survive and thrive in their environment. Scientists are still researching why these lizards evolved to have green blood, but it's likely related to their diet and physiology.
