The nose knows: A canine's olfactory powers are well known -- dogs are now even being used to sniff out rare types of cancer -- and that natural ability hasn't gone unnoticed by the U.S. military. When President Barack Obama traveled to Asia last fall, an elite team of 30 bomb-sniffing dogs were part of his security entourage. (All in all, it was a pretty cushy assignment: The dogs stayed in 5-star hotels and rode in vehicles tailored to their comfort and safety.)
More remarkable still are vapor-wake dogs. Scientists at Auburn University's College of Veterinary Medicine have genetically bred and specially trained canines to not only detect stationary bombs or bomb-making materials, but identify and alert their handler to the moving scent of explosive devices and materials left behind in the air, say, as a suicide bomber walked through a crowd -- all without ever tipping off the perpetrator. While not as expensive as some military-trained dogs, the cost of breeding and training these dogs cost is not cheap at around $20,000 each.
Above, U.S. sergeant Matthew Templet and his bomb-sniffing dog Basco search for the explosives in an abandoned house in Haji Ghaffar village during a clearance patrol in Zari district of Kandahar province on Dec. 27, 2010.
BEHROUZ MEHRI/AFP/Getty Images