level is used for absorbing sound matter by animal
animal_ear is not ear. herd_animal is air_breathing_vertebrate. herd_animal is not air_breathing_vertebrate. animal_ear is ear. animal_noise is not audible_sound. animal_noise is audible_sound. sound_frequency is sensory_information. animal_part_region_function is reifiable_function. animal_utterance is audible_sound. deaf_animal is hearing_impaired_thing.