- A dog can track objects with its nose thanks to a nasal cavity that is rich with blood vessels and nerve endings. These nerve endings connect to a highly developed olfactory center in the brain. A dog uses this information to track an item by following that scent path. A dog's nose is a million times more sensitive than a human nose, or about as sensitive as a human eye.
- Humans have used dogs in warfare since the Roman times, when soldiers equipped them with spike collars and sent them forward to attack the enemy, according to the website of the United States War Dog Association. Humans first used them as detection dogs in the U.S. in World War II. They were used as auxiliaries and trained to scout fighting fields for mines and traps before human soldiers. Dogs also pulled sleds and carried messages.
- Detection dog breeding programs are carefully managed so breeding females have the relevant working drive, problem-solving ability and temperament to pass on to puppies, according to the website Act Detection Dogs. A breeder will monitor puppies from 8 weeks old and take out any animal that does not have the necessary temperament or problem-solving abilities. All animals must be able to cope with unfamiliar places and environments, urban situations, noises and humans.
- Humans use food as a reward when training detection dogs. Humans hide toys to force puppies to sniff them out, and a puppy is rewarded with a treat every time it finds the toy. A trainer will make the objects progressively more difficult to find and reward the animal with food each time it successfully finds the object. Trainers transfer this to real-life situations and turn each search into a game for the detection dog.
- A dog can use its nose to find narcotics, explosive, lost victims of natural disasters and contraband, according to the Dog Owners Guide website. Humans use them in warfare, airports, military installations, police and fire departments, immigration points, and in search and rescue teams. Dogs are also used to find human remains. Bodies release oils that dogs smell in the air, soil and water, according to an article by Jessica Dudenhofer in the Daily News. Dogs have been able to find 1,500-year-old remains.