Question

why do polar bears walruses have large bodies with lots of fats?

Answer 1

They have stored body fats due to 2 reasons.
Firstly they live in the polar regions which are excessively cold so the fat present in the epidermal layer of the skin function as insulator which doesnot allows the body heat to escape out thus help them to survive in cold atmosphere.
Secondly their body fat provides the energy needed by the cells, to perform their function during hybernation when they doesnot have any intake of food.