Thursday, June 10, 2010

"Essentially Modern Waterfowl" in the Cretaceous
"Fowl were the first neognath lineages to evolve. From the limited fossils that have to date been recovered, the conclusion that they were already widespread - the predominant group of modern birds - by end of the Cretaceous is generally accepted nowadays. Fossils such as Vegavis indicate that essentially modern waterfowl - albeit belonging to a nowadays extinct lineage - were contemporaries of the (non-avian) dinosaurs."

is a genus of extinct bird that lived during the Late Cretaceous (Maastrichtian stage) of Antarctica, some 65 mya. It belonged to the clade Anseriformes. Among modern birds, Vegavis is most closely related to ducks and geese (Anatidae), but it is not considered to be a direct ancestor of them.[1]
The discovery of the type species, Vegavis iaai, demonstrates that the major groups of bird alive today had already diversified in the Cretaceous. This supports the longstanding phylogenetic inferences of paleornithologists.[citation needed] It has been hailed as the first definitive physical proof that representatives of some of the groups of modern birds lived in the Mesozoic.[1]"
"We have more data than ever to propose at least the beginnings of the radiation of all living birds in the Cretaceous," Clarke says. "We now know that duck and chicken relatives coexisted with non-avian dinosaurs. This does not mean that today's chicken and duck species lived with non-avian dinosaurs, but that the evolutionary lineages leading to today's chicken and duck species did." (Julia A. Clarke1,2, Claudia P. Tambussi3, Jorge I. Noriega4,
Gregory M. Erickson5,6,7 & Richard A. Ketcham8)

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