Archaeopteryx suggested that "Archaeopteryx" was a dinosaur that was no more closely related to birds than were other dinosaur groups. Kurzanov (1987) suggested that "Avimimus" was more likely to be the ancestor of all birds than "Archaeopteryx". Barsbold (1983) and Zweers and Van den Berge (1997) noted that many maniraptoran lineages are extremely birdlike, and they suggested that different groups of birds may have descended from different dinosaur ancestors. The discovery of the closely related "Xiaotingia" in 2011 led to new phylogenetic analyses that suggested that "Archaeopteryx" is a deinonychosaur rather than an avialan, and therefore, not a "bird" under most
Archaeopteryx or trunk-climbing lifestyle. This has been interpreted as evidence of theropod ancestry. In 1988, Gregory S. Paul claimed to have found evidence of a hyperextensible second toe, but this was not verified and accepted by other scientists until the Thermopolis specimen was described. "Until now, the feature was thought to belong only to the species' close relatives, the deinonychosaurs." The Thermopolis Specimen was assigned to "Archaeopteryx siemensii" in 2007. The specimen is considered to represent the most complete and best-preserved "Archaeopteryx" remains yet. The discovery of an eleventh specimen was announced in 2011, and it was described in 2014. It