The origin of the Basques and the Basque language is a controversial topic that has given rise to numerous hypotheses. Modern Basque, a descendant or close relative of Aquitanian and Proto-Basque, is the only Pre-Indo-European language that is extant in western Europe. The Basques have therefore long been supposed to be a remnant of a pre-Indo-European population of Europe. The main hypotheses about the origin of the Basques are: Native origin, the mainstream theory, according to which the Basque language would have developed over the millennia entirely between the north of the Iberian Peninsula and the current south of France, without the possibility of finding any kind of relationship between the Basque language and other modern languages in other regions. Basque-Iberism theorizes the existence of a kinship between the Basque and the Iberian language, and therefore between their speakers. Caucasian origin theorizes that the Basque language and the languages of the Caucasus may have a direct relation, explaining why they share some linguistic typologies absent in the Indo-European languages. Native origin theory According to Stephen Oppenheimer, from c.16,000BC, the warmer climate allowed the expansion of proto-Basque groups, or proto-Europeans, across the north of Africa and the entire continent of Europe, expanding the Magdalenian culture across Europe. In 2008, the Finnish linguist Kalevi Wiik proposed that the current Basque language is the remainder of a group of "Basque languages" that were spoken in the Paleolithic throughout western Europe and that retreated with the progress of the Indo-European languages. Wiik states that his theory coincides with the homogeneous distribution of the Haplogroup R1b in Atlantic Europe.<ref>[http://www.jogg.info/41/Wiik.pdf Kalevi Wiik Were did european men come from (2008)]</ref> Ludomir R. Lozny states that "Wiik's controversial ideas are rejected by the majority of the scholarly community, but they have attracted the enormous interest of a wider audience." Paleogenetic investigations In May 2012, the National Geographic Society Genographic Project released a study that showed through detailed DNA analysis of samples from French and Spanish Basque regions that Basques share unique genetic patterns that distinguish them from the surrounding non-Basque populations. The results of the study clearly support the hypothesis of a partial genetic continuity of contemporary Basques with the preceding Paleolithic/Mesolithic settlers of their homeland. Paleogenetic investigations by the Complutense University of Madrid indicate that the Basque people have a genetic profile coincident with the rest of the European population and that goes back to Prehistoric times.