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Molecular evidence for a terrestrial origin of snakesBiologists have debated the origin of snakes since the nineteenth century. One hypothesis suggests that snakes are most closely related to terrestrial lizards, and reduced their limbs on land. An alternative hypothesis proposes that snakes are most closely related to Cretaceous marine lizards, such as mosasaurs, and reduced their limbs in water. A presumed close relationship between living monitor lizards, believed to be close relatives of the extinct mosasaurs, and snakes has bolstered the marine origin hypothesis. Here, we show that DNA sequence evidence does not support a close relationship between snakes and monitor lizards, and thus supports a terrestrial origin of snakes.
Document ID
Document Type
Reprint (Version printed in journal)
External Source(s)
Vidal, Nicolas (NASA Headquarters Washington, DC United States)
Hedges, S. Blair
Date Acquired
August 23, 2013
Publication Date
May 7, 2004
Publication Information
Publication: Proceedings of the Royal Society of London. Series B. Biological sciences
Volume: 271 Suppl 4
ISSN: 0962-8452
Subject Category
Life Sciences (General)
Distribution Limits