en image, confondre généalogie et phylogénie
Living dinosaurs: How birds took over the worldFrom the toucans of the tropics to the penguins of the Antarctic, ours is a world of birds. They are among the most successful of land animals – and have been for a very long time. If a birdwatcher could step back 70 million years, they would be absolutely dazzled by the birds on show.
But the evolutionary history of birds has long been an enigma. Ever since a single fossil feather was dug up 150 years ago, the origins of birds have been one of biology's most contentious issues.
That has all changed with a string of recent discoveries, most notably the famous feathered dinosaurs of China. In a little over a decade these have transformed our understanding of bird origins.
It is all a far cry from when that first feather was found in a quarry at Solnhofen in southern Germany. The exact date of discovery is disputed – some accounts say 1860, others 1861 – but we do know it was quickly followed by a near-complete skeleton of its presumed owner, archaeopteryx. This 145-million-year-old enigma combined the teeth and long tail of a dinosaur with the wings and feathers of a bird. It assumed enormous importance as a "missing link" between two animal groups, exactly as Charles Darwin had predicted in 1859.
Archaeopteryx continues to be an icon of evolution, with new insights about it being made every year, but it has now been joined by dozens of bird-like dinosaurs and dinosaur-like birds, all helping to finally tell the full story of bird origins. Here is New Scientist's round-up of where we stand on the biggest questions.
Only now can we say beyond reasonable doubt that birds aren't just built like dinosaurs – they actually are dinosaurs. Continue reading
It had the wings and feathers of a bird, but the teeth, legs and claws of a dinosaur – so just what kind of beast was archaeopteryx? Continue reading
Ancestors of the dinosaurs may have sported feathers long before the first dino took a leap of faith. Continue reading
The late Cretaceous skies contained oddities to bamboozle any modern birdwatcher, but a few familiar sights too. Continue reading
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