Evolution & Natural History

Salamanders are classified in the class Amphibia, which comes from the Greek word meaning double life due to the fact that they live both an aquatic and terrestrial existence. Salamanders and Newts make up the Amphibian order Caudata. The term "newt" refers to those Caudata which spend their adult lives chiefly in water and are termed family Salamandridae. "Salamanders," on the other hand, are aquatic as larvae and proceed to live a terrestrial life during adulthood. There are 9 families in the order Caudata and over 350 species in existence today. The family of plethodontids includes the majority of salamander species. Their life on land and a lack of lungs that enables them to breath through their skin, identify them.

The Caudata is the oldest order of existing terrestrial vertebrates. The salamanders evolved from the Labrynthodonts, the first vertebrates to venture onto land in the Devonian period over 350 million years ago. The first fossilized salamander to be discovered was found in Germany in 1725, but was misidentified at the time as the skeleton of a human who had perished in Noah's Flood. Today, it is dated to the Miocene period, about 15 million years ago, and is given the name Andrias scheuchzeri. The earliest recognized salamander was a seven-inch skeleton found in Kazakhstan, USSR and was named Karaurus. It dates to the late Jurrassic approximately 140 million years ago. Karaurus is believed to have evolved from a group of Labrynthodonts called Branchiosaurs. Most modern salamander families evolved in what is now the eastern United States.

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