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Bird Archaeopterix was not bird! Who is the ancestor of avian kingdom?

Archaeopterix was considered famous for 150 years as the ancestor of all birds. In reality he was just another dinosaur with the feel of flying, say scientists after the recent discovery in China of a "cousin" the size of a chicken.

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Since the discovery of the first skeleton Archaeopterix in Bavaria in 1861, most experts considered this evolving dinosaur with feathers as the oldest type of bird. The "phylogenetic tree", which sets out the family of species Archaeopterix logically took place basic branch "Aviarelor" from which modern birds draw.

Over time, some researchers have had some doubts when those features regarded as typical attributes "bird" in Archaeopterix (feathers, hull, three-toed feet, etc..) Have been discovered in other dinosaurs, and they were terrestrial. But in the absence of formal evidence, "grandfather" Archaeopterix continue to rule the kingdom avian imperturbable.

Professor Xing Xu, a renowned specialist in paleontology from the Chinese Academy of Sciences, studied the fossil of a dinosaur with feathers trivial, weighing only 800 grams, found in Liaoning Province. It was a new species, named Zheng Xiaotingia very close Archaeopterix, but whose morphology undoubtedly a link to a branch parallel "aviarelor" called "deinonichozaur," explained the Chinese scientists in a study published in the journal Nature.

When Professor Xu and his team have introduced features of Xiaotingia the computer model allows phylogenetic tree composition, Archaeopterix "fell" on his arm, to find the origin of neighboring branches deinonichozaurilor.

"In other words, Archaeopterix ceased to be a bird," said Lawrence Witmer American biologist.

"Surprised by this result, the authors analyze the same parameters resumed, this time omitting Xiaotingia. And Archaeopterix was restored to his place Aviarelor branch, based on all birds," said Witmer.

Although Professor Xu remained cautious and said that currently still have too little data to support his new "phylogenetic hypothesis," this result does not ultimately nothing more than to confirm a number of assumptions made in recent years , with the discovery of fossils.

"Perhaps it is time to accept that Archaeopterix was only a small carnivorous dinosaur with feathers that others who walk through the Jurassic," ago 145-200 million years, says Lawrence Witmer.

Archaeopterix first skeleton was discovered less than two years after publication of the famous volume "Origin of Species" by Charles Darwin.

With its mixture of reptilian and avian features, this dinosaur was discovered at the ideal time to illustrate the evolution of species and could influence the way scientists work afterwards.

But where lies the common ancestor of birds? According to Professor Xu analysis, it must be sought near Epidexipterix, Jeholornis and Sapeornic, only recently discovered species that is "new territory, even for specialists," according to Lawrence Witmer.

Tags: new discover from dinosaurus world, dinosaurs time new info, information, 2011.07.29