Photo of the Day 28 December 2007

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.