Archaeopteryx lithographica

Archaeopteryx lithographica is one of the most informative fossils in the study of the dinosaur–bird transition. Skeletons from the fine-grained Solnhofen limestones preserve asymmetrical wing feathers, tail plumage and, in some specimens, feathers over the body and hind limbs. Beneath that plumage lay a small theropod skeleton with sharp teeth, three clawed fingers, a furcula and a long series of tail vertebrae. Wing-bone geometry supports powered flapping flight, probably in short bursts and with a stroke unlike that of most living birds.

Its fossils occur between approximately 150.8 and 148.5 million years ago. Values shown here are approximate and reflect the current curated seed dataset.

The forelimbs formed broad feathered wings with asymmetric primary and secondary feathers. A long bony tail carried paired feathers rather than the short fused pygostyle of modern birds. The jaws retained small teeth, each hand had three separate clawed fingers, and many skeletal elements remained unfused. A furcula and flight-adapted feather arrangement link it with birds, while the long tail, toothed jaws and grasping fingers retain the ancestral theropod condition. Extensive pennaceous feathers on the body and hind limbs show that complex plumage was not limited to the flight surface.

• Asymmetrical primary and secondary feathers forming broad wings
• Long bony tail carrying paired pennaceous feathers
• Small toothed jaws rather than a modern toothless beak
• Three separate clawed fingers on each feathered forelimb
• Furcula and flight-capable shoulder and wing construction
• Pennaceous body and hind-limb plumage preserved in informative specimens
• Many hand, pelvic and vertebral bones less fused than in modern birds

An isolated feather found in the Solnhofen limestone region in 1860 led Hermann von Meyer to name Archaeopteryx lithographica in 1861. Later that year a much more complete feathered skeleton was discovered; the British Museum bought it in 1862, and Richard Owen described it in 1863. A spectacular second skeleton found in the 1870s became the Berlin specimen. Because the isolated feather's identity and diagnostic value remained disputed, the International Commission on Zoological Nomenclature designated the London skeleton NHMUK PV OR 37001 as the neotype in 2011, making it the specimen that now anchors the species name.

Discovery credit: Solnhofen-area quarry workers.

Naming authors: Hermann von Meyer.

Archaeopteryx lived among low subtropical islands around warm, shallow lagoons in what is now Bavaria. Fine carbonate mud on quiet lagoon floors produced the lithographic limestones that preserve feathers and other delicate structures. The same deposits contain insects, lizards, fish, crustaceans, pterosaurs and the small theropod Compsognathus. The fossils may have been transported from islands or shorelines into hypersaline lagoon waters, so the slabs record burial habitat more directly than everyday living habitat.

Cross-sectional geometry inside the wing bones is consistent with active flapping flight rather than gliding alone, probably in short bursts. Its flight stroke and shoulder were not identical to those of most modern birds, and researchers still debate launch style, endurance and agility. Clawed fingers and curved foot claws could assist climbing or perching, but the degree to which Archaeopteryx lived in trees versus on the ground remains unresolved. It probably ate small animals such as insects and lizards, although its full diet is not preserved as a simple species-wide menu.

• The isolated feather that inspired the name in 1861 is no longer the official name-bearing fossil; the London skeleton became the neotype in 2011.
• The first skeleton reached the British Museum in 1862 and is still on public display in London's Cadogan Gallery.
• Berlin's exceptionally complete original specimen is displayed in the Museum für Naturkunde's World of Dinosaurs exhibition.
• Microscopic pigment structures indicate that one isolated wing feather was predominantly black, but they do not show that the entire animal was black.
• Calling Archaeopteryx the single 'first bird' is an oversimplification: bird origins form a branching evolutionary transition, and its precise position among early avialans and close paravian relatives remains debated.

A research repository is not necessarily a public exhibit. Loan and display status can change, so check with the institution before visiting.

1. 01
   The Paleobiology Database

   Open source
2. 02
   Archaeopteryx

   Natural History Museum, London

   Open source
3. 03
   The World of Dinosaurs

   Museum für Naturkunde Berlin

   Open source
4. 04
   Opinion 2283 (Case 3390) Archaeopteryx lithographica von Meyer, 1861 (Aves): conservation of usage by designation of a neotype

   International Commission on Zoological Nomenclature · Bulletin of Zoological Nomenclature · 2011

   Open source
5. 05
   Wing bone geometry reveals active flight in Archaeopteryx

   Dennis F. A. E. Voeten, Jorge Cubo, Emmanuel de Margerie and 5 coauthors · Nature Communications · 2018

   Open source
6. 06
   New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers

   Christian Foth, Helmut Tischlinger, Oliver W. M. Rauhut · Nature · 2014

   Open source