What is the traditional classification system of birds?

Compared with bird DNA classification system, the traditional bird classification system is a widely used classification system. This system is mainly based on the classification system of J. L. Peter, which integrates the research results of morphology, biogeography, ecology, behavior, embryology and paleontology, and has been widely used all over the world.

Taxonomically, birds belong to the ornithoptera of the animal kingdom-Chordata-Vertebrates. All the existing birds belong to the current suborder ornithopoda, with more than 9000 species in 3 orders.

Extended data birds can be found in most land habitats, distributed on seven continents, and even snow swallows can be found in the inland of Antarctic continent, 440 kilometers away from the ocean. The diversity of birds is most remarkable in the tropics.

In the early days, people thought that the high diversity in the tropics was the result of high speciation, but recent research found that high speciation also occurred in high latitudes, but it was offset by the higher extinction rate in the tropics. Many birds can live on land and in the sea. Some seabirds go ashore just to breed, and some penguins can dive to a depth of 300 meters.

Baidu Encyclopedia-Traditional Bird Classification System