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Modern Dinosaurs Although we think of dinosaurs as extinct they are in fact all around us birds are dinosaurs. The idea that birds and dinosaurs are closely related is not new. Indeed the dinosaur-bird controversy dates back to Darwin with the discovery of Archopteryx ancient wing in 1861. It was described by Richard Owen in the Philosophical Transactions of the Royal Society 1863. This was quite fortuitous because Darwins Origin had just been published and transitional forms were a topic of debate. Hugh Falconer wrote to Darwin in January 1863 You were never more missed...for there has been this grand Darwinian case of the Archopteryx...Had the Solenhofen quarries been commissionedby august command to turn out a strange being la Darwinit could not have executed the behest more handsomelythan in the Archopteryx. Archopteryx was a strange fossil indeed. It had feathers but it also had reptilian features like a long bony tail and unfused bones in the wrist and ankle. Archopteryx also had teeth but that was not known until the late 1870s when the Berlin specimen was discovered the first specimen had no head. Owen who was opposed to Darwins theory was quick to classify it strictly as a bird and downplay its transitional nature but to others it was further evidence of a close evolutionary link between the two groups. Compsognathus a small theropod dinosaur caught T. H. Huxleys attention. He thought it was very bird-like and wrote about it in a paper entitled On the Animals Which are Most Nearly Intermediate Between Birds and Reptiles Geological Magazine 1868. To Huxleys point a specimen now in the Jura Museum in Eichsttt was originally identified as Compsognathus. Only when it was reexamined later was it determined to be a birdan Archopteryx no less. Huxley would refer to Compsognathus again when making an even more daring proposition It is certain that Compsognathus must have walked on its hind legs. The question then naturally arises did the gigantic dinosaurs such as Iguanodon and Megalosaurus have the same mode of progression This seems at first sight hard to believe but there is considerable reason for thinking it may have been the case. And he was right. We now know that many dinosaurs were bipedal. In a later paper Further Evidence on the Affinity between the Dinosaurian Reptiles and Birds published in the Quarterly Journal of the Geological Society in 1870 Huxley compared the hip structure of an emu dinosaur and crocodile and concluded there was an unmistakable transition between reptiles and birds. The dinosaur-bird hypothesis fell out of favor in the early twentieth century because the theropod specimens known at the time did do not have collarbones which when fused together form the furcula or wishbone in birds. Thus scientists concluded that birds must have descended from an earlier predinosaurian ancestor. It turns out however that theropods not only have collarbones they are already fused into the signature wishbone. The early specimens were either incomplete or the furcula had been misidentified. With that problem out of the way the theory reemerged in the 1970s. 45