The reptile family tree below includes only living reptiles. The phylogeny of the reptiles is in a state of considerable flux, and some of the relationships indicated below may be regarded as controversial. The traditional taxonomy, with its neat division into turtles, crocodiles, snakes and lizards, has become inadequate to capture the complexities of this fascinating group of animals. Because the reptiles are a group of such great interest,I have attempted to make a simplified representation of relationships thought to exist among the various reptilian taxa. This has been a daunting task for somebody practicing herpetology without a license. The tree you see below has been redrawn from cladograms and other information from several sources; the phylogeny of the squamates has recently been updated from molecular data (Vidal and Hedges, 2005). However, the fault for any errors or misinterpretations in the tree rests with me, not with the original source. I have omitted some branches in the interest of simplification; I hope your personal favorite is not among them. Corrections of errors, gross omissions or misinterpretations will gratefully be received. With the exception of the Tuataras, examples of all of the reptilian taxa below can be seen at the Fort Worth Zoo's outstanding Herpetarium.
Giant Madagascar Day Gecko
Atitlan Alligator Lizard
(Oaxacan Rock Lizard)
Green Tree Monitor
Mexican Beaded Lizard
Northwestern Neotropical Rattlesnake
Honduran Milk Snake
To the Amphibians
To the Birds
Australian Snake-necked Turtle
Indian Star Tortoise
*Examples of snakes and lizards not pictured here can be seen at this page from the University of Aberdeen Zoology Museum.
Sources of information:
- Harry Greene. Snakes: the Evolution of Mystery in Nature. University of California Press
- ( Read an excerpt from the book)
- Peter A. Meylan and Eric Ganko. Higher Relationships of Testudines.
- Cyberlizard's Rough Guide to the Lizard Families.
- Anthony Herrell. Lizards in the Lab
- Kevin de Queiroz and Emilia P. Martins. Unversity of Arizona's Tree of Life (Squamata)
- Philip J. Heise, et al. Higher-Level Snake Phylogeny Inferred from Mitochondrial DNA Sequences of 12s rRNA and 16s rRNA Genes. Mol. Biol. Evol. 12 (1995): 259-265.
- S. Blair Hedges and Laura L. Poling. A molecular phylogeny of reptiles. Science 283 (12 February 1999): 998-1001.
- Nicholas Vidal and S. Brail Hedges. A phylogeny of squamate reptiles (lizards, snakes and amphisbaenians) inferred from nine nuclear protein-coding genes. C. R. Biologies 328 (2005): 1000-1008.