The common name for several species of black birds in the Crow family and Crow genus. Also known as Lao Lu, his mouth is filled with joyful cries. It is the largest bird in the Passeriformes order, with a body length of about 50 centimeters. The whole body or most of the feathers are blackish black, hence the name. It mainly inhabits various forest types such as broad-leaved forests, mixed coniferous and broad-leaved forests, coniferous forests, secondary mixed forests, and artificial forests in low mountains, plains, and mountainous areas, especially sparse forests and forest edge zones. Most of them are resident birds. Strong clustering, with a group of up to tens of thousands of individuals. The behavior is complex and exhibits strong intellectual and social activities. Generally fierce in personality, rich in aggressive habits, often preying on eggs and chicks in waterfowl and wading bird nests. Omnivorous.

Hippopotamus is a semi aquatic mammal belonging to the family Hippopotamus in the order Artiodactyla. Hippopotamus is the largest omnivorous mammal in freshwater. The word hippopotamus means' horse in the river ', which is the Greek term for this powerful beast. Hippos are mainly distributed in tropical regions of Africa, inhabiting swamps and reed beds near rivers. Hippopotamuses often live in groups, move around at night, and spend most of their time soaking in water. They have a gentle temperament. Hippos have a huge appetite, mainly feeding on aquatic plants such as reeds, and sometimes also on land crops such as green grass on the shore. The high value of hippopotamus's long teeth is one of the reasons for their rapid decline.