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Crocodile Eyes Are Designed for Ambush Attacks

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The visual systems of crocodiles are more cleverly designed than previously thought, facilitating their ambush hunting techniques and semi-aquatic lifestyles.

Nicolas Nagloo, a PhD student from The University of Western Australia’s School of Animal Biology, explains that crocodiles are excellent predators that quietly wait at the water’s edge before attacking their prey with a burst of speed. “They are experts at ambushing prey while remaining concealed, and their heightened vision plays a big role in this,” Nagloo said. “The water surface makes up the majority of the bottom of the visual field, and the visual horizon occurs along the riverbanks where crocodiles see best.”

While the vision of saltwater and freshwater crocodiles is similar above the water’s surface, the light conditions they experience underwater are significantly different. “In freshwater habitats there is a lot of long wavelength [red] light,” Nagloo said. “In contrast, saltwater habitats have a broader range of wavelengths, providing a greater amount of short wavelength [blue] light.”

Nagloo’s research, published in the Journal of Experimental Biology (http://tinyurl.com/jpb8nrc), compared the eyes of the two crocodile species and found that instead of having a compact fovea (a depression in the retina where...

The full text of this article can be purchased from Informit.