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This study contributes to this debate by reporting on two key aspects of this fossil that are visible under ultraviolet (UV) light. In contrast to previous studies, we show that most of the vertebral column of the Berlin<jats:italic>Archaeopteryx<\/jats:italic>possesses intraosseous pneumaticity, and that pneumatic structures also extend beyond the anterior thoracic vertebrae in other specimens of<jats:italic>Archaeopteryx<\/jats:italic>. With a minimum Pneumaticity Index (PI) of 0.39,<jats:italic>Archaeopteryx<\/jats:italic>had a much more lightweight skeleton than has been previously reported, comprising an air sac-driven respiratory system with the potential for a bird-like, high-performance metabolism. The neural spines of the 16<jats:sup>th<\/jats:sup>to 22<jats:sup>nd<\/jats:sup>presacral vertebrae in the Berlin<jats:italic>Archaeopteryx<\/jats:italic>are bridged by interspinal ossifications, and form a rigid notarium-like structure similar to the condition seen in modern birds. This reinforced vertebral column, combined with the extensive development of air sacs, suggests that<jats:italic>Archaeopteryx<\/jats:italic>was capable of flapping its wings for cursorial and\/or aerial locomotion.<\/jats:p>","DOI":"10.1038\/s41598-019-42823-5","type":"journal-article","created":{"date-parts":[[2019,4,24]],"date-time":"2019-04-24T10:03:10Z","timestamp":1556100190000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Ultraviolet light illuminates the avian nature of the Berlin Archaeopteryx skeleton"],"prefix":"10.1038","volume":"9","author":[{"given":"Daniela","family":"Schwarz","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Kundr\u00e1t","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helmut","family":"Tischlinger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gareth","family":"Dyke","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan M.","family":"Carney","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2019,4,24]]},"reference":[{"key":"42823_CR1","doi-asserted-by":"publisher","first-page":"1199","DOI":"10.1002\/jmor.10470","volume":"267","author":"MP O\u2019Connor","year":"2006","unstructured":"O\u2019Connor, M. 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