Why Do Some Lizards Have Green Blood?

The prehensile tailed skink from the highlands of New Papua New Guinea has green blood due to high concentrations of the green bile pigment biliverdin. The green bile pigment in the blood overwhelms the intense crimson color of red blood cells resulting in a striking lime-green coloration of the muscles, bones, and mucosal tissues.

Scientists are trying to figure out how green-blooded lizards might benefit from the unusual pigment. The answer could provide new insights into human illnesses like jaundice and malaria.

(Image credit: Courtesy of Christopher C. Austin/LSU)