Stubborn animals are known for their unwillingness to cooperate or be controlled. Two of the most common stubborn animals are ASSES and MULES. ASSES are members of the horse family, and are known for their stubbornness and intelligence. MULES are a hybrid between a donkey and a horse, and are also known for their stubbornness and strength. Both animals are used in agriculture and transportation due to their strength and hardiness.