Pigs have an undeserved reputation for being dirty animals, but in reality, they are incredibly clean. They choose specific areas for their waste and avoid contaminating their living spaces.

Some animals make that easy by preening, licking, and grooming themselves. But others seem not to care about getting dirty as they splash in puddles and investigate smelly garbage bags.

Snakes are exclusively carnivorous, meaning that they only eat other animals — and in some cases, eggs. Their diets range ...