Photo of the Day 90

Hammerhead Shark, Bahamas, 2007

Photograph by Brian Skerry

Primordial in appearance, great hammerheads, like this one near the Bahamas, are actually among evolution's most advanced sharks. Wide-set eyes and nostrils provide keen peripheral senses, and tiny electroreceptors on its snout help it pinpoint prey. Dozens of serrated teeth do the rest.

(Text adapted from and photo shot on assignment for, but not published in, "Blue Waters of the Bahamas: An Eden for Sharks," March 2007, National Geographic magazine)