Evolution of birds extinction event 66 million years ago, giving rise to ostriches and relatives (Paleognathae), ducks and relatives (Anseriformes), ground-living fowl (Galliformes), and “modern birds” (Neoaves). Phylogenetically, Aves is usually defined as all descendants of the most recent common ancestor of a specific modern bird species (such as the house sparrow, "Passer domesticus"), and either "Archaeopteryx", or some prehistoric species closer to Neornithes (to avoid the problems caused by the unclear relationships of "Archaeopteryx" to other theropods). If the latter classification is used then the larger group is termed Avialae. Currently, the relationship between dinosaurs, "Archaeopteryx", and modern birds is still under
Specimens of Archaeopteryx a fish. Fragments of the braincase and upper jaw were later identified and published by other researchers. While Owen's 1863 monograph on the specimen is historically considered to be the first real description of "Archaeopteryx", Henry Woodward, assistant of the Geological Department of the British Museum, had published a shorter article on the specimen in December 1862. Here he provided a detailed description as well as the first published illustration of the specimen, sketched from the original. Rather than an attempt to steal Owen's glory, Woodward gave him due credit in this article as its official describer. Woodward's article nevertheless