The bird’s long feathers maintain the body’s constant temperature; the forelimbs are winged, the hind limbs are walking, most of them can fly, the range of activities is wide, and some wings are degraded, but not flying, and the active area is relatively small.
There are many types and numbers of birds, and they are found all over the world. Some birds live and reproduce in their reproductive areas throughout the year, do not migrate due to seasonal changes, and some birds migrate on time every year.
Birds are closely related to humans. Some birds can kill pests and rodents, protect crops and trees, and some birds can be seen. In order to protect the ecological environment, it is necessary to protect the beneficial birds and prohibit the killing.