Ursa Major is the best known of the constellation and it appears in every reference known. Ursa Major, the Great Bear, is visible in the Northern Hemisphere all year long.
Calisto was changed to a bear because of Zeus's jealousy and transferred her to the sky. This is improbable, as the constellation was already well established before this time.
The drawings all show a bear with a long tail, again not likely correct since bears have no tails. The most likely explanation for the bears and one which I find intriguing is the fact that Native Americans called the constellations the bear, but…