How many species of birds and living orders exist today?

As of 2024, there are roughly 11,000 described living species of birds classified across 44 orders, though some estimates suggest the true number could be closer to 20,000. Taxonomy in this field remains very fluid due to ongoing DNA analysis. More than half of all bird species belong to a single order known as passerines, or perching birds.

What we know

• There are approximately 11,000 described living species of birds as of 2024, categorized into 44 orders. [2, 4]
• Alternative estimates place the real number of bird species at almost 20,000. [2] · medium confidence
• Passerines, or perching birds, account for well over 5,000 species, making up more than half of the world's total bird species. [2, 4]
• Bird taxonomy is considered very fluid because of modern DNA analysis. [2]

Still open

• The exact total number of real bird species remains uncertain, with estimates ranging from 11,000 to nearly 20,000.
• The precise relationships between non-avian dinosaurs, Archaeopteryx, and modern birds are still under active debate.

Where to go next

• compared withWhat is the Sibley-Ahlquist bird taxonomy?
• whenHow did modern birds evolve after the dinosaur extinction?
• a case in pointWhat defines the order of perching birds or passerines?
• the bigger pictureHow do scientists use ornithology to study ecology and evolution?
• what caused itWhich lineages of birds survived the Cretaceous-Paleogene extinction?
• an unexpected connectionHow are birds classified as reptiles in modern cladistics?Although traditional Linnaean taxonomy placed birds in their own unique class due to warm-blooded morphology, modern cladistic analysis groups them as living reptiles and the only surviving dinosaurs.

Sources

• [1]list of birds (Wikidata Q28854985) · CC0 1.0
• [2]List of birds · CC BY-SA 4.0
• [3]Ornithology · CC BY-SA 4.0
• [4]Bird · CC BY-SA 4.0
• [5]Evolution of birds · CC BY-SA 4.0