Taxonomy (systematics of the class of birds in particular) is one of the oldest sections of the complex of biological sciences. Its main goal is to identify the entire diversity of organisms, develop the theoretical and practical foundations for their classification, and establish family ties between individual species and groups of species. Without this, it is not possible to navigate the diversity of the surrounding organic world.
Tasks of taxonomy
The main tasks of bird systematics are as follows:
- identification, description and subsequent designation of bird species, not only existing, but also fossils;
- determining the causes and factors of speciation.
Historical Brief
The first attempt to systematize animal species was made by Aristotle in the 4th century BC. He united all known to himbirds in one genus - Ornithes. The system was imperfect, but this did not prevent it from existing until the second half of the 17th century.
For the first time, birds were divided into groups according to morphological and external features by the English biologist F. Willoughby in the book Ornithologiae libri tres, which was designed and published after his death in 1676. It was this scientific source that Carl Linnaeus later actively used when creation of the "System of Nature", including the taxonomy of birds. He introduced binomial nomenclature and hierarchical categories to designate species, which are still in use today. The Linnaean system included six classes (categories), one of them, along with amphibians, worms, fish, insects and mammals, was occupied by birds (Aves).
The third stage in the development of systematics falls on the beginning of the 19th century. At this time, the attention of researchers was focused on studying evolution within a species and finding out its paths. Modern bird taxonomy appeals to such a concept as "infraclass of fan-tailed birds", or "real birds". Let's take a closer look at them.
Infraclass fantails
Infraclass unites all known fossils and birds now living on earth, possessing a certain feature. It is expressed in a sharply shortened caudal spine and the fusion of the last 4-6 vertebrae into a special bone called the pygostyle, to which tail feathers are attached. Currently, the subclass is divided into two superorders: ratites and new palatine. Together theyunite 40 modern orders of birds and three extinct ones.
Rateless birds
Obsolete names of this superorder sound like ostrich, running or smooth-chested birds. It is not numerous, in accordance with modern taxonomy of birds without a keel, there are only 58 species, divided into five orders:
- Kiwi-shaped detachment. Includes one family and genus of the same name. Five endemic species (large and small gray, northern brown, common kiwi and Apteryx rowi) are known to live in New Zealand.
- Nandu-shaped detachment. Consists of one family and genus, represented by two species: common and Darwin rhea.
- The ostrich order is represented by a single species - the African ostrich (pictured above).
- Tinamu-shaped detachment. The largest group of ratites, including 47 species grouped into 9 genera.
- Squad of cassowaries, or Australian ostriches. It includes two families. The first is a cassowary, represented by two species, and the second is an emu with a single species of the same name.
In addition, the subclass of ratites has three extinct orders: epiornithes, lithornithes and moas.
New Palatine Birds
According to the current taxonomy of birds, this subclass is the most numerous and includes more than 9,000 species, and this is the vast majority of all modern birds. Their main feature is the structure of the palate,there are no other distinguishing features. Keeled birds are represented by both flying and flightless species. One of the largest representatives is a condor with a wingspan of up to 3.2 m. And the smallest bird is a hummingbird. The first fossil remains of neopalates date back to the Cretaceous period, i.e. about 70 million years ago.
Let's list the 35 orders that are distinguished by the modern taxonomy adopted by the International Union of Ornithologists. Chicken-like birds are known, if not by everyone, then by many - this is one of the most common groups of birds. The most common and numerous bird is the domestic chicken. Other units:
- storks (ankles);
- goation;
- Anseriformes;
- passerines;
- petrel-like (tube-nosed);
- pigeon;
- loons;
- bustoid;
- crane;
- woodpecker;
- cariamoid;
- cuckoo;
- chicken;
- goats;
- pelicans (copepods);
- Madagascar cowgirls;
- grebes;
- parrots;
- mousebirds;
- Gannet;
- penguin;
- hornbills;
- charadriiformes;
- ribbed;
- Raksha;
- falconiformes;
- sun herons;
- swift;
- turkey;
- owls;
- trogon-shaped;
- phaeton-shaped;
- flamingos;
- hawks.
The International Union of Ornithologists does not recognize the detachment of American vultures identified by many modern taxonomists. It is regarded as a family of the same name, belonging to the hawks.
