E-Mail It is estimated that canines possess up to 300 million olfactory receptors in their nose, compared to about 6 million in humans. Not only that, but the part of a dog's brain devoted to analyzing smells is about 40 times greater than in humans. Therefore, it's no wonder pooches are extremely useful tools in the job of detection, whether they're finding explosives, drugs, chemicals or myriad substances. In the last several years, detection canines have increased in popularity, deployment and success as environmental surveyors for range and wildlife species. Their ability to detect species in the environment has even shown to be more reliable in some cases than standard surveying technologies.