Internal Adaptation for the Tree Lizard

So far in this class we have talked about many external adaptations in animals for flight. However the Neon Blue-Tailed Tree Lizard shows that animals can adapt internally as well to help them take to the skies.

The Holaspis guentheri, or the Neon Blue-Tailed Tree Lizard, hails from a large area in Africa, where its natural habitat is in the forests. They can grow to be up to 12 centimeters in length, but the average is 9 to 11cm. As their name suggests they have line of very bright blue running down their tail. In addition there are also lighter yellow stripes down the body of the lizard.

A study done in 2009 using the Neon Blue-Tailed Tree Lizard and two similar lizards showed that although the tree lizard shows no external adaptations for flight it still indeed was gliding. The team calculated how far the lizard would fall if it just jumped off a 2 meter high object and fell like a rock. The tree lizard was on average going about one half meter for every two meters of height. After their calculation they found that this is .2 meters farther than their calculation predicted.  The only problem was they did not know was why these lizards were still able to glide.

At first they thought that the Tree Lizard might be altering its body mid-air, much like the flying snake does. After careful examination of the video they took though, they found that this was not the case. So what was causing the Tree Lizard to outperform its relatives?

The team brought the two other lizards and the Tree Lizard in to get x-rays. They found that the other two lizards had very typical bone structure, however the Tree Lizard was unique. The Tree Lizard had a slender build, and the bones had not ossified as much as they had in the other two lizards. These less dense bones are not as massive as its relatives are, and thus the Tree Lizard has become the superior glider of the three.

This finding is important not just because it has identified another animal as having some sort of aerial capabilities, but rather that we must look beyond just the external adaptations that animals have.  Perhaps there are more species out there that have unique adaptations that we cannot just simply see.

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  1. Journal of Experimental Biology. “Neon Blue-tailed Tree Lizard Glides Like A Feather, Thanks To Light Bubbly Bones.” ScienceDaily, 22 Jul. 2009. Web. 10 Oct. 2011.
  2. Bieke Vanhooydonck, Greet Meulepas, Anthony Herrel, Renaud Boistel, Paul Tafforeau, Vincent Fernandez and Peter Aerts. Journal of Experimental Biology. Ecomorphological analysis of aerial performance in a non-specialized lacertid lizard, Holaspis guentheri, 19 May 2009.  10 Oct. 2011.

One Comment

Lorena Barba posted on October 10, 2011 at 3:46 pm

hi Nathan,
Fantastic contribution to the course blog! This is a different point of view from all that we’ve discussing, and it’s so interesting. Of course, birds have light bones, too, so this is very suggestive.