~Archaeopteryx~the earliest bird
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Archaeopterygiformes
Family: Archaeopterygidae
Genus: Archaeopteryx
Species: ithographica
PHYSICAL CHARACTERISTICS:
Archaeopteryx (meaning "ancient wing") is a very early prehistoric bird, dating from about 150 million years ago during the Jurassic period, when many dinosaurs lived. It is one of the oldest-known birds. Archaeopteryx had a wingspan of about 1.5 feet (0.5 m) and was about 1t foot ( 30 cm) long from beak to tail. It probably weighed from 11 to 18 ounces (300 to 500 grams).This crow-sized animal may have been able to fly, but not very far and not very well. Although it had feathers and could fly, it had similarities to dinosaurs, including its teeth, skull, lack of a horny bill, and certain bone structures.
EVOLUTION:
Paleontologists think that Archaeopteryx was a dead-end in evolution and that coelurosaurian theropods (a group of dinosaurs that included the Dromaeosaurs Deinonychus, Utahraptor, and Velociraptor) led to the birds.
FOSSILS RECORD:
Amazingly detailed Archaeopteryx fossils have been found in fine-grained Jurassic limestone in southern Germany. This fine-grained limestone is used in the lithographic process, hence the species name "lithographica" given to the early Archaeopteryx specimen. The first Archaeopteryx fossil (a feather) was found in 1860 near Solnhofen, Germany, and was named by the German paleontologist Hermann von Meyer in 1861. That year he also discovered the first specimen of Archaeopteryx. A total of eight Archaeopteryx specimens have been found, plus the feather.
The Feather:
Found in 1860 near Solnhofen and a revelation when it was described by H. v Meyer in 1861. The surprise was not the age of the fossil, since several ornithopod dinosaur footprints erroneously ascribed to birds were known from the Triassic, but the detail that was preserved.
Archaeopteryx specimens:
The London Specimen:Found in 1861, near Langenaltheim. Probably the best known (together with the Berlin specimen). Its discovery was announced by H. v Meyer in 1861 and the specimen was subsequently bought by the British Museum of Natural History in London (under the instruction of Richard Owen). It cost 700 UK Pounds - a small fortune in those times, but for that price Owen also received just over a thousand other fossils from Solnhofen. The specimen was sold by amateur collector and local doctor Carl Haberlein, who had received it in lieu of payment for medical treatment. Owen described the specimen in 1863. He saw at once that it was an important find and recognised that it represented a transitional form - but not in the "Darwin" sense. Owen was a staunch "evolutionist", however he did not believe in Darwin's model of evolution. Interestingly Huxley, who was a staunch "Darwinist" failed to recognise the true import of the fossil and merely remarked on it as a "reptile-like bird". It wasn't until close comparisons were made with the dinosaur Compsognathus that Archae's true worth was realised.
The Berlin Specimen:Found in 1877 near Blumenberg. This was a better specimen than the London specimen, principally because it had a complete head, albeit badly crushed, and was snapped up by the Berlin museum. It was sold to them by Carl Haberlein's son (talk about keeping it in the family!). It was described by W. Dames in 1884
The Maxburg Specimen:Found in 1958 near Langenaltheim (same as London Specimen). This specimen is of the torso only and is the only specimen to still be in private hands. In 1992, after the death of its finder and owner Eduard Opitsch, the specimen was found to be missing and it is thought that it was sold secretly (Abbott 1992). It's whereabouts remain unknown. The specimen was described by Heller in 1959.
The Haarlem or Teyler Specimen:This specimen was actually found near Reidenburg in 1855, 5 years before the feather! It lay in a museum after being classified as Pterodactylus crassipes by H. v Meyer in 1875. Curiously, Mayer described it as having a flight membrane unlike any other known pterodactyl, now we know why! A re-examination of the fossil in 1970 by Ostrom revealed feathers and its true identity.
The Eichstatt Specimen:Found near Workerszell in 1951, it was described by P. Wellnhofer in 1974. This is the smallest of all the specimens, being some 2/3 the size of the others. It also differs in other aspects such as the tooth structure and the poorly ossified shoulder bones. It has been suggested that this is a separate genus, however the differences can also be ascribed to the possible juvenile stage of the animal and/or a different feeding niche. However, this specimen has the best preserved head, from which the litany of Archae's reptilian cranial features were described. At the moment it still resides within A. lithographica.
The Solnhofen Specimen:Found in the 1960's near Eichstatt by a Turkish worker. First identified as Compsognathus, by a amateur collector, however, further examination showed that the arms were too long for the body size and preparation revealed feather traces. Described by P. Wellnhofer in 1988.
Soft tissue remnants discovered in Archaeopteryx fossil:
It boasts more than just beautiful impressions of long-gone feathers. One of the world's most famous fossils – of the earliest known bird, Archaeopteryx – also contains remnants of the feathers' soft tissue.
"It's amazing that that chemistry is preserved after 150 million years," says Roy Wogelius, a geochemist at the University of Manchester, UK. Wogelius and colleagues scanned the "Thermopolis specimen" using a powerful X-ray beam from a synchrotron at the Stanford Synchrotron Radiation Lightsource in California.
The synchrotron excites atoms in target materials to emit X rays at characteristic wavelengths. The scan reveals the distribution of elements throughout the fossil. The green glow of the bones in this false-colour image shows that Archaeopteryx, like modern birds, concentrated zinc in its bones. The red of the rocks comes from calcium in the limestone that had encased the fossil since the animal died.
Copper and zinc are key nutrients for living birds, and their presence in the fossil bones shows the evolutionary link with dinosaurs. The study also revealed phosphorous along the main shaft of the feathers in the fossil: palaeontologists had long thought that only impressions remained.
Class: Aves
Order: Archaeopterygiformes
Family: Archaeopterygidae
Genus: Archaeopteryx
Species: ithographica
PHYSICAL CHARACTERISTICS:
Archaeopteryx (meaning "ancient wing") is a very early prehistoric bird, dating from about 150 million years ago during the Jurassic period, when many dinosaurs lived. It is one of the oldest-known birds. Archaeopteryx had a wingspan of about 1.5 feet (0.5 m) and was about 1t foot ( 30 cm) long from beak to tail. It probably weighed from 11 to 18 ounces (300 to 500 grams).This crow-sized animal may have been able to fly, but not very far and not very well. Although it had feathers and could fly, it had similarities to dinosaurs, including its teeth, skull, lack of a horny bill, and certain bone structures.
EVOLUTION:
Paleontologists think that Archaeopteryx was a dead-end in evolution and that coelurosaurian theropods (a group of dinosaurs that included the Dromaeosaurs Deinonychus, Utahraptor, and Velociraptor) led to the birds.
FOSSILS RECORD:
Amazingly detailed Archaeopteryx fossils have been found in fine-grained Jurassic limestone in southern Germany. This fine-grained limestone is used in the lithographic process, hence the species name "lithographica" given to the early Archaeopteryx specimen. The first Archaeopteryx fossil (a feather) was found in 1860 near Solnhofen, Germany, and was named by the German paleontologist Hermann von Meyer in 1861. That year he also discovered the first specimen of Archaeopteryx. A total of eight Archaeopteryx specimens have been found, plus the feather.
The Feather:
Found in 1860 near Solnhofen and a revelation when it was described by H. v Meyer in 1861. The surprise was not the age of the fossil, since several ornithopod dinosaur footprints erroneously ascribed to birds were known from the Triassic, but the detail that was preserved.
Archaeopteryx specimens:
The London Specimen:Found in 1861, near Langenaltheim. Probably the best known (together with the Berlin specimen). Its discovery was announced by H. v Meyer in 1861 and the specimen was subsequently bought by the British Museum of Natural History in London (under the instruction of Richard Owen). It cost 700 UK Pounds - a small fortune in those times, but for that price Owen also received just over a thousand other fossils from Solnhofen. The specimen was sold by amateur collector and local doctor Carl Haberlein, who had received it in lieu of payment for medical treatment. Owen described the specimen in 1863. He saw at once that it was an important find and recognised that it represented a transitional form - but not in the "Darwin" sense. Owen was a staunch "evolutionist", however he did not believe in Darwin's model of evolution. Interestingly Huxley, who was a staunch "Darwinist" failed to recognise the true import of the fossil and merely remarked on it as a "reptile-like bird". It wasn't until close comparisons were made with the dinosaur Compsognathus that Archae's true worth was realised.
The Berlin Specimen:Found in 1877 near Blumenberg. This was a better specimen than the London specimen, principally because it had a complete head, albeit badly crushed, and was snapped up by the Berlin museum. It was sold to them by Carl Haberlein's son (talk about keeping it in the family!). It was described by W. Dames in 1884
The Maxburg Specimen:Found in 1958 near Langenaltheim (same as London Specimen). This specimen is of the torso only and is the only specimen to still be in private hands. In 1992, after the death of its finder and owner Eduard Opitsch, the specimen was found to be missing and it is thought that it was sold secretly (Abbott 1992). It's whereabouts remain unknown. The specimen was described by Heller in 1959.
The Haarlem or Teyler Specimen:This specimen was actually found near Reidenburg in 1855, 5 years before the feather! It lay in a museum after being classified as Pterodactylus crassipes by H. v Meyer in 1875. Curiously, Mayer described it as having a flight membrane unlike any other known pterodactyl, now we know why! A re-examination of the fossil in 1970 by Ostrom revealed feathers and its true identity.
The Eichstatt Specimen:Found near Workerszell in 1951, it was described by P. Wellnhofer in 1974. This is the smallest of all the specimens, being some 2/3 the size of the others. It also differs in other aspects such as the tooth structure and the poorly ossified shoulder bones. It has been suggested that this is a separate genus, however the differences can also be ascribed to the possible juvenile stage of the animal and/or a different feeding niche. However, this specimen has the best preserved head, from which the litany of Archae's reptilian cranial features were described. At the moment it still resides within A. lithographica.
The Solnhofen Specimen:Found in the 1960's near Eichstatt by a Turkish worker. First identified as Compsognathus, by a amateur collector, however, further examination showed that the arms were too long for the body size and preparation revealed feather traces. Described by P. Wellnhofer in 1988.
Soft tissue remnants discovered in Archaeopteryx fossil:
It boasts more than just beautiful impressions of long-gone feathers. One of the world's most famous fossils – of the earliest known bird, Archaeopteryx – also contains remnants of the feathers' soft tissue.
"It's amazing that that chemistry is preserved after 150 million years," says Roy Wogelius, a geochemist at the University of Manchester, UK. Wogelius and colleagues scanned the "Thermopolis specimen" using a powerful X-ray beam from a synchrotron at the Stanford Synchrotron Radiation Lightsource in California.
The synchrotron excites atoms in target materials to emit X rays at characteristic wavelengths. The scan reveals the distribution of elements throughout the fossil. The green glow of the bones in this false-colour image shows that Archaeopteryx, like modern birds, concentrated zinc in its bones. The red of the rocks comes from calcium in the limestone that had encased the fossil since the animal died.
Copper and zinc are key nutrients for living birds, and their presence in the fossil bones shows the evolutionary link with dinosaurs. The study also revealed phosphorous along the main shaft of the feathers in the fossil: palaeontologists had long thought that only impressions remained.
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