Widely set eyes give hammerhead sharks exceptional binocular vision
The hammerhead shark’s head is one of the strangest in the animal world. The flattened hammer, known as a ‘cephalofoil’, looks plain bizarre on the face of an otherwise streamlined fish, and its purpose is still the subject of debate. Is it an organic metal detector that allows the shark to sweep large swathes of ocean floor with its electricity-detecting ability? Is it a spoiler that provides the shark with extra lift as it swims? All of these hypotheses might be true, but Michelle McComb from Florida Atlantic University has confirmed at least one other -the hammer gives the shark excellent binocular vision. The T-shaped hammerhead configuration also allows the sharks to see 360 degrees, with respectable stereo rear view.
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McComb, D. M., Tricas, T. C. and Kajiura, S. M. (2009). Enhanced visual fields in hammerhead sharks. J. Exp. Biol. 212, 4010-4018.