In 2015, a paper called "New chronology for Ksar Akil (Lebanon) supports Levantine route of modern human dispersal into Europe" by Marjolein D Bosch from Cambridge University, Amy L. Prendergast from Melbourne University, Marcello Antonio Mannino from Aarhus University, Jean-Jacques Hublina, Tamsin C. O’Connell, Beatrice Demarchid, Sheila M. Taylore, Laura Nivena and Johannes van der Plicht was submitted for reveiw on 23 January, edited by Gilbert Tostevin, University of Minnesota and published in June for the National Academy of Science. Their paper supported the Levantine corridor hypothesis.
The hypothesis had previously been questioned by the chronology of Ksar Akil, known for deeply stratigraphied Initial (IUP) and Early (EUP) Upper Paleolithic sequences containing human remains. Radiocarbon test dates of shell ornaments from the site were later than the start of the first Upper Paleolithic in Europe. New evaluations of a skeleton known as "Egbert" (43,200 an 42,900 cal B.P.) and a maxilla known as "Ethelruda" (before ~45,900 cal B.P.) brought the site's chronology in line with other Levantine IUP and EUP sites, demonstrating that modern humans associated wtih Upper Paleolithic toolkits in the Levant predated all modern human fossils from Europe. The age of Ethelruda is significant with regards the spread of modern humans carrying the Initial Upper Paleolithic into Europe and suggests the initial colonization of Europe was a rapid process.