A lounging lizard might not bask just for warmth — it may be getting a much-needed hit of vitamin D. A new study reports that panther chameleons set their sunbathing schedule depending on how much vitamin D they need. The research, published online and in the May/June Physiological and Biochemical Zoology, shows how adept animals are at responding to bodily needs and has implications for how conservation groups, zoos and pet owners care for their reptilian critters, scientists say.
“This provides good evidence that animals will seek ways to regulate,” comments Mark Acierno of Louisiana State University’s School of Veterinary Medicine in Baton Rouge. “It really calls attention to the fact that providing ample opportunity for basking is important.”
Science used to have a more narrow view of basking, says behavioral ecologist Kristopher Karsten of Texas Christian University in Fort Worth, who led the new study. Turtles dozing on logs and still lizards atop sunny rocks were thought to be regulating their body temperature. But scientists have begun investigating ulterior motives for the behavior, which can also leave an animal vulnerable to predators. Regulating levels of vitamin D, a vitamin important for reproductive success in reptiles, may be another reason to sit and sun.