Archaeopteryx

About Archaeopteryx

The Evolutionary "Missing Link" and the Oldest Feather

Archaeopteryx is one of the most iconic animals in the history of paleontology, living in the Late Jurassic about 150 million years ago. It has served as the evolutionary "missing link" connecting bipedal carnivorous dinosaurs (theropods) and modern birds.

The first fossil that gave this animal its name was not a skeleton, but a single "feather" discovered in the summer of 1860 or 1861 near Solnhofen, Germany. German paleontologist Hermann von Meyer named this unprecedented feather fossil "Archaeopteryx," meaning "ancient wing" in Greek.

Shortly after the discovery of the feather, a nearly complete skeleton with clear feather impressions (the London Specimen) was found. The year was 1861, just two years after Charles Darwin published "On the Origin of Species." This fossil shocked the scientific community of the time as conclusive evidence that birds branched off and evolved from reptiles (dinosaurs).

Butterfly-style Flapping and Complete Wing Surface

Whether Archaeopteryx could actually fly was a subject of intense debate for over 150 years. Due to its skeletal structure, it was once thought incapable of the powerful flapping of modern birds, and could only glide from tree to tree.

However, in 2018, an international research team used cutting-edge X-ray technology called a "synchrotron" to examine the internal structure of its wing bones, revealing an astonishing fact. The bone strength of Archaeopteryx was very similar to that of modern pheasants and quails, which fly in short bursts. It was concluded that rather than moving their wings up and down like modern birds, they engaged in "powered flight," propelling themselves into the air with a unique stroke, powerfully throwing their wings forward to catch the air, similar to the "butterfly" stroke in swimming.

Features Connecting Dinosaurs and Birds

Archaeopteryx displays a mix of reptilian (dinosaur) and avian features. It has sharp teeth in its jaws, three fingers with claws on its forelimbs, and a long bony tail. These are clearly features of carnivorous dinosaurs known as theropods. At the same time, it possesses structures unique to birds, such as asymmetrical flight feathers and a wishbone (furcula).

Furthermore, recent research has revealed that not only their "external appearance" for flying, but also their unseen "insides of the mouth" were highly evolved. Ultraviolet and CT scans of the aforementioned Chicago Specimen revealed the presence of a "hyoid bone" deep in the mouth to support muscles. This suggests they had a flexible tongue capable of freely manipulating prey.

Traces of fleshy projections called "oral papillae" on the roof of the mouth (palate) to push food into the esophagus and prevent regurgitation, as well as a network of sensory organs at the tip of the beak to locate prey, were also discovered. Since flying consumes an enormous amount of energy, they had simultaneously developed an advanced digestive and foraging mechanism to efficiently ingest calories to compensate.

The Miracle of Preservation - The Environment of Solnhofen

About 150 million years ago, the Solnhofen region in Germany, where Archaeopteryx fossils were found, consisted of islands scattered across a vast, tropical shallow sea. Around these islands, poorly circulated "lagoons" had formed.

In the dry climate, seawater evaporated, leaving the bottom of the lagoons filled with highly saline, completely anoxic water. In this toxic environment, not even scavengers or decomposing bacteria could survive.

When an Archaeopteryx flying overhead or living on a nearby island died and fell into this lagoon, it quietly sank into the fine mud without decomposing. Thanks to this process, not only did the skeletons remain intact, but even the feathers and highly delicate tissues inside the mouth were preserved as vivid fossils, resembling lithographs, down to the modern day.
The limestone in this region has long been mined as a material for lithography, and this industrial quarrying activity brought about the discovery of the century: Archaeopteryx.

Diverse "Archaeopteryx" Specimens

Since the discovery of the feather in 1861, 14 skeletal specimens and one feather have been scientifically reported to date. For a long time, these were all considered the same "Archaeopteryx," but recent analysis indicates they actually comprise a mix of various closely related dinosaur species.

London Specimen (Specimen Number BMNH 37001)

Discovered in 1861, this is the first skeletal fossil. It retains beautiful feather impressions and became crucial evidence supporting Darwin's theory of evolution. At the time, Richard Owen of the British Museum of Natural History purchased it for the exorbitant sum of 700 pounds, and it remains housed in London today.

Berlin Specimen (Specimen Number HMN 1880/81)

Discovered in 1874 or 1875, it is the most complete and beautiful specimen. Almost the entire body is present, including the skull lined with teeth, and it is sometimes hailed as the "most beautiful fossil in the world." The image we typically associate with "Archaeopteryx" is largely based on this specimen.

Haarlem Specimen (Teylers Specimen) (Specimen Number TM 6428/29)

Discovered in 1855, it is a partial fossil actually found before the first feather fossil. It was initially misidentified as a pterosaur. Later identified as Archaeopteryx, a 2017 study revealed it is a different genus closely related to the Chinese dinosaur "Ostromia."

Daiting Specimen (Eighth Specimen)

Discovered in 1990 and kept hidden in a private collection for a long time, it underwent scientific investigation in 2018. Found in a slightly newer rock layer than other specimens, it possesses features closer to modern birds, such as a fused skull and hollowized (pneumatized) bones, and was described as a new species, "Archaeopteryx albersdoerferi."

Solnhofen Specimen (Specimen Number BMMS 500)

Discovered in 1987, it is characterized by being larger than other specimens. Initially described as a different genus, the prevailing view now considers it a species of Archaeopteryx.

Eichstätt Specimen (Specimen Number JM 2257)

Discovered in 1951. It is a matched pair of slab and counterslab, speculated to be a juvenile.

Chicago Specimen (14th Specimen)

The newest specimen acquired by the Field Museum of Natural History in the U.S. in 2022. Only the size of a pigeon, it is the smallest known individual. Its highly delicate skeleton is preserved three-dimensionally, bringing numerous major discoveries that unravel the mysteries of Archaeopteryx's flight and diet, such as the aforementioned "tertial feathers," "hyoid bone," and "oral papillae."

Archaeopteryx Stamp & Fossil Gallery