How are birds classified in the traditional classification system?

Birds can be divided into 2 suborders based on their morphological and structural characteristics: Archaeornithes and Archaeopteryx. The Archaeornithes, whose species have long been extinct and only have fossilized specimens, is called Archaeopteryx lithographica, and is an intermediate type that evolved from reptiles to birds.

The present-day bird subclass (Neornithes), also known as the new bird subclass, can be divided into the dentate-maxillar general order, flat-breasted general order, penguin general order and sudden-breasted general order **** 3 general order, in addition to the dentate-maxillar general order (such as dusky birds), reptiles in the morphological structure and physiological characteristics than amphibian is more complete, and therefore in the Mesozoic era had a flourishing, not only a wide range of species, but also the body size and life style of the different, occupying the Therefore, this geological era is also called the Age of Reptiles.

Expanded Information

Birds can be found in most terrestrial habitats, and are distributed on all seven continents, with snow petrels found 440 kilometers inland from the sea in Antarctica. The diversity of birds is most remarkable in the tropics.

Earlier it was thought that the high diversity in the tropics was the result of high levels of speciation, but more recent studies have found that high levels of speciation also occur at high latitudes, but are offset by higher rates of extinction than in the tropics. Many families of birds can live on land as well as in the sea, with some seabirds coming ashore only to breed and some penguins diving to depths of up to 300 meters.

Baidu Encyclopedia - Birds