Large and broad noses exhibit more sense of scent. The bull-dog has large noses hence good sense of scent rather than greyhound which has narrow nose.
Longer the nose the more watchful and guarded is the individual. The large nose helps deep breathing which in turn accelerates blood circulation. The brain is also strengthened because of volume of blood circulated into it.
From the transition of ape to man, nose has important function. Intellectual development is in direct proportion of the size of nose. As the development of the nose of Negros has remained stationary, that race kept the same size of nose for thousands of years. So their intellectual development has been slower.
The intestinal system has representations in the nose. The fullness of the sides of the nose denotes intestinal health.
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