an animal requires oxygen for to breathe
mammal is air_breathing_vertebrate. herd_animal is not air_breathing_vertebrate. herd_animal is air_breathing_vertebrate. mammal is not air_breathing_vertebrate. all_mammals_breathe_air_and has lungs oxygen is oxygen. all_mammals_breathe_air_and has not lungs oxygen_mask is breathing_device. humans_must has oxygen_to_remain_conscious air has oxygen