Question

Polar bear have small ears because

Answer 1

The polar bear's small ears and tail offer less surface area than large ears or tails, and help maintain body warmth. Fat. Polar bears have a layer of fat that can be four inches (10 cm) thick. Although their fur is the primary source of insulation, the fat helps keep heat in as well.

Answer 2

Polar bears have small and rounded ears. These ears are important because they help prevent water entering their ears which could then freeze and damage their ear drums. Also less body heat is lost out of the small ears. Other adaptations of the polar bear include hollow fur that traps hair inside.
Idk if it helps was on google and saw this and was backed up by quora