Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Share Flipboard Email. Bob Strauss. Science Writer. Updated October 01, Featured Video. Cite this Article Format. To advance the debate, researchers have increasingly put Archaeopteryx under the microscope.
For Clarke, ancient variation is to be expected. In the late Jurassic, evolution was in its sketching phase, as a menagerie of feathered dinosaurs haltingly took to the air. Only then could evolution refine flight to what it is today. All rights reserved. Share Tweet Email. Why it's so hard to treat pain in infants. This wild African cat has adapted to life in a big city.
Animals Wild Cities This wild African cat has adapted to life in a big city Caracals have learned to hunt around the urban edges of Cape Town, though the predator faces many threats, such as getting hit by cars. India bets its energy future on solar—in ways both small and big. Environment Planet Possible India bets its energy future on solar—in ways both small and big Grassroots efforts are bringing solar panels to rural villages without electricity, while massive solar arrays are being built across the country.
Go Further. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser or turn off compatibility mode in Internet Explorer. In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Analysis of fossil traits suggests that Archaeopteryx is not a bird at all.
The latest discovery of a fossil that treads the line between birds and non-avian dinosaurs is leading palaeontologists to reassess the creature that has been considered the evolutionary link between the two. Archaeopteryx has long been placed at the base of the bird evolutionary tree. It has traits that have helped to define what it is to be a bird, such as long and robust forelimbs. Yet in recent years, the discoveries of numerous small, feathery dinosaurs have created a conundrum for palaeontologists, raising questions about which animals are the ancestors of modern birds and which are just closely related cousins.
The fossil that is driving the latest Archaeopteryx rethink is called Xiaotingia zhengi , and is described in Nature today 1 by Xing Xu, a palaeontologist at the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, and his colleagues.
It was found in western Liaoning, China, in rocks dating to the Late Jurassic epoch, million— million years ago. Like many similar fossils, it is surrounded by feather impressions in the rock, but has claws on the ends of its forelimbs and sharp teeth. These traits by themselves do little to help place the fossil in the dinosaur—bird transition, but Xu reports that it also has extremely long middle and last finger bones and a wishbone with an L-shaped cross-section at one end.
These characteristics, Xu argues, identify Xiaotingia as very closely related to Archaeopteryx and another feathery relative, Anchiornis. After analysing the traits present in Xiaotingia and its relations, Xu and his colleagues are suggesting that the creatures bear more resemblance to the dinosaurs Velociraptor and Microraptor than to early birds, and so belong in the dinosaur group Deinonychosauria rather than in the bird group, Avialae.
It likely seized small prey with just its jaws, and may have used its claws to help pin larger prey. Archaeopteryx was first discovered in or , when a solitary feather was unearthed from limestone deposits near Solnhofen, Germany.
This feather, however, may have come from another, undiscovered proto-bird. In , the first Archaeopteryx skeleton, which was missing most of its head and neck, was unearthed near Langenaltheim, Germany. As a form of payment, it was given to a doctor, who later sold it to the London Natural History Museum. The discovery coincided with the publication of Darwin's "On the Origin of Species," and the specimen, dubbed the London Specimen, seemed to confirm his theories.
Through various transactions, the fossil, which is the first found to have an intact head, eventually wound up being in the Humboldt Museum fur Naturkunde, where it still resides.
The 12th and last Archaeopteryx specimen to be found was discovered in and announced in , but hasn't yet been scientifically described.
Recent discoveries from China, Mongolia and Argentina have shaken up what paleontologists knew about the relationship between stem-birds and bird-like theropods. In , scientists uncovered a fossil in Liaoning, China, whose combination of features unexpectedly suggested Archaeopteryx was actually just a relative of the lineage that ultimately gave rise to birds.
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