Archaeopteryx for flightless birds. In 2010, Robert L. Nudds and Gareth J. Dyke in the journal "Science" published a paper in which they analysed the rachises of the primary feathers of "Confuciusornis" and "Archaeopteryx". The analysis suggested that the rachises on these two genera were thinner and weaker than those of modern birds relative to body mass. The authors determined that "Archaeopteryx" and "Confuciusornis", were unable to use flapping flight. This study was criticized by Philip J. Currie and Luis Chiappe. Chiappe suggested that it is difficult to measure the rachises of fossilized feathers, and Currie speculated that "Archaeopteryx" and "Confuciusornis"
Specimens of Archaeopteryx the feather. "Archaeopteryx lithographica" was initially named for this original feather, rather than the full skeleton that was found around the same time, and the feather was originally the formal type specimen and holotype for the species. There are obvious problems with this idea, such as the fact that the feather may have come from a juvenile, or possibly another species altogether. The distal obtuse angle at the tip is not a feature found on the feathers of any other "Archaeopteryx" skeleton with integument imprints. It is possible, however, that the strange angle of the tip is an artifact caused