who is learning to signal when she detects a scent, is supposed to select the vanillin, a training aid that will later be switched to ammonium nitrate used in explosives. If she selects correctly, she'll be rewarded with a treat. She gets the first one right, choosing vanillin, misses the next two, but then got the fourth one right. At that point, she was averaging 50-50, which is not good, but she was still a beginner with time to learn. Biting machine? Though war dogs may be high profile these days -- thanks in part to Cairo , the Belgian Malinois who accompanied Navy Seals on the Osama bin Laden raid -- there were virtually no deployed military bomb dogs working on battlefields when the US invaded Iraq, and hadn't been for decades. After the Vietnam War, the military's working dog programme was handed over to the Air Force, which used them to patrol missile fields in the United States. Those dogs were used to being guided on leashes, living in air-conditioned kennels and working limited shifts: a far cry from a war zone. That quickly changed with the arrival of IEDs and in 2007, 13 dogs -- all Labs -- were deployed with the Marines to Iraq and Afghanistan. When the dogs started finding bombs, Marines asked for more, and today there are some 600 dogs. Whilst successful, they were all essentially prototypes for the next generation of bomb dog. "After we do all this science, we're going to