Ключевые слова: africa, african, aggressive, angry, animal, aquatic, behavior, big, black, displaying, dusit zoo, eye, fat, gray, grey, head, heavy, herbivore, herd, hippo, hippopotamus, huge, jaw, kenya, lake, large, mammal, mouth, natural, nature, river, small, south, thailand, tooth, water, wetland, white, wide, wild, wildlife, zoo,