It is widely known that dogs have an excellent sense of smell, but scientists are still discovering how advanced dogs' smelling capabilities are. Dogs are able to smell many things that humans cannot. For example, dogs can detect boxes that contain electricity from those that don't. Researchers believe dogs are able to smell the tiny amounts of ozone released from electricity, thanks to their keen sense of smell.
Dogs breathe very differently than humans do. They are constantly drawing more air into their nostrils, which gives them more opportunity to analyze for scents. Dogs' noses have around 200 to 300 million sensory receptors which makes them very sensitive to even the slightest scents and compounds in air. Human noses have only about 6 million sensory receptors. In fact, dogs can even smell cancer in humans, although they do need to be trained to look for the scents caused by cancer cells.
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Dogs are a "gift from God" and scientists are too stupid to see what "talents" dogs have. They are more than pets; they are an unusual non-human friend to man.
Instead, scientists get involved in many stupid projects with butterflies, fish, monkeys, etc. and waste money there instead of getting the gold mine from the unusual power of dogs. Scientists can be bright and stupid at the same time.