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An eye for the land
  1. Ivan R Schwab,
  2. David J Maggs
  1. University of California, Davis, Sacremento, California, USA
  1. Correspondence to: Professor I R Schwab University of California, Davis, 4860 Y street, Suite 2400, Sacremento, CA 95817, USA; irschwab{at}

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Tetrapods gained ground in the late Devonian period, over 360 million years ago (mya), a profound advance requiring major changes in anatomy and physiology. Early tetrapods remained partially aquatic and fettered to water, but other terrestrial niches would beckon requiring dissolution of those bonds.

The first lizard appeared approximately 350 mya in the early Carboniferous period but this creature did not resemble modern lizards. This stem organism would give rise to several classes including Squamata, the class that would beget modern lizards and snakes. Terrestrial freedom permitted radiation into a brighter and more defined environment, and the visual system would have to respond to this challenge.

Basiliscus galeritus, pictured on the cover, represents the lizards and the complexity of their lifestyle. This mostly carnivorous reptile must accomplish visually complex tasks as it is a diurnal predator of invertebrates and other vertebrates. It also illustrates the visual imperative placed upon lizards as they became terrestrial.

In Greek legend, the basilisk is the king of serpents. According to most versions of the legend, the basilisk was a huge lizard endowed with a crest or crown, …

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  • Cover image courtesy of Joe Burgess, The International Reptile Conservation Fund works to conserve reptiles and the natural habitats and ecosystems that support them. Histopathologic assistance from Christopher M Reilly, D.V.M.