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"
Ancestor Ancestor An ancestor is a parent or (recursively) the parent of an antecedent (i.e., a grandparent, great-grandparent, great-great-grandparent, and so forth). "Ancestor" is "any person from whom one is descended. In law the person from whom an estate has been inherited." Two individuals have a genetic relationship if one is the ancestor of the other, or if they share a common ancestor. In evolutionary theory, species which share an evolutionary ancestor are said to be of common descent. However, this concept of ancestry does not apply to some bacteria and other organisms capable of horizontal gene transfer. Some research suggests