Why bear stand on hind legs
For a more apparent vision, so that they can see distance more than they can see when standing on all four legs.
For a more clear smell, their bear smell sense is powerful, and can observe food and female polar bears from miles.
In a standing position, they earn more height and can smell the smell carried by the wind more certainly.
A mother polar bear stands up to watch whether its cubs are comfortable and whether a male polar bear is searching for her or not.
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