Archaeopteryx Archaeopteryx Archaeopteryx (), meaning "old wing" (sometimes referred to by its German name ("original bird" or "first bird")), is a genus of bird-like dinosaurs that is transitional between non-avian feathered dinosaurs and modern birds. The name derives from the ancient Greek ("archaīos") meaning "ancient", and ("ptéryx"), meaning "feather" or "wing". Between the late nineteenth century and the early twenty-first century, "Archaeopteryx" had been generally accepted by palaeontologists and popular reference books as the oldest known bird (member of the group Avialae). Older potential avialans have since been identified, including "Anchiornis", "Xiaotingia", and "Aurornis". "Archaeopteryx" lived in the Late Jurassic around
Most recent common ancestor all of the modern population. Due to pedigree collapse, modern individuals may still exhibit clustering, due to vastly different contributions from each of ancestral population . Most recent common ancestor In biology and genealogy, the most recent common ancestor (MRCA, also last common ancestor (LCA), or concestor) of any set of organisms is the most recent individual from which all the organisms are directly descended. The term is also used in reference to the ancestry of groups of genes (haplotypes) rather than organisms. The MRCA of a set of individuals can sometimes be determined by referring to an established pedigree.