The bear is the animal with the best sense of smell, and bears have been known to find food sources that are 18 miles (28.9 km) away. In fact, bears have a sense of smell that is estimated to be more than seven times stronger than that of a bloodhound, the breed of dog that is used for hunting by scent. Although the specific area of the bear's brain that is used for recognizing scents is proportional to that of the same area in other animals, bears are thought to have such a strong sense of smell because of the size of the nasal mucous membrane in their heads. It is about 100 times larger than the nasal mucous membrane area in humans.
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