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[QUOTE]Originally posted by the lioness,: [QB] [b]Ancient Local Evolution of African mtDNA Haplogroups in Tunisian Berber Populations[/b] Sabeh FrigiLotfi CherniKarima Fadhlaoui-zidAmel Benammar-Elgaaied Human Biology, Volume 82, Number 4, August 2010, n the present work, mtDNA data show a diversified distribution of African haplogroups. However, a question remains concerning the date of the sub-Saharan African inputs. Our results demonstrate an ancient local evolution in Tunisia of some African haplogroups (L2a, L3*, and L3b). The most ancient haplogroup is L3*, which would have been introduced from eastern sub-Saharan populations to North Africa about 20,000 years ago. The Siwa oasis sample studied by Coudray et al. (2009) contains sub-Saharan haplogroups L0a1, L3i, L4*, and L4b2, which are different from our Tunisian samples, in agreement with the heterogeneity of Berbers already shown in Tunisia.Stevanovitch et al. (2004) suggested that the Gurna population in Egypt has conserved the trace of an ancestral genetic structure from an ancestral East African population characterized by a high haplogroup M1 frequency. This haplogroup is also present in three Berber populations (Kesra, Matmata, and Sned) with vari-able frequencies. In each of these populations, haplogroup L3* is also present. The association of both eastern African haplogroups in the Berber populations is a strong argument in favor of eastern African gene flow in Berbers. Other genetic and archaeological studies confirmed the crucial idea that an ancient population in East Africa constituted the basis of the ancestors of all African Upper Paleolithic populations—and their subsequent present-day descendants (Bengtson 2008; Keita 2004; Relethford 2000; Zakrzewski 2003, 2007) Moreover, Berber languages spoken exclusively by North African popula-tions belong to the Afro-Asiatic language. Diakonoff (1998) showed an exclusively African origin (Diakonoff, 1981, 1988) for the family. He explicitly described proto-Afro-Asiatic vocabulary as consistent with non-food-producing vocabulary and linked it to pre-Neolithic cultures in the Levant and in Africa south of Egypt. Moreover, Ehret (2003) suggested that early Afro-Asiatic languages were spread by Mesolithic foragers from Africa into the Levant. On the contrary, Diamond and Bellwood (2003) suggested that food production and the Afro- Asiatic lan-guage family were brought simultaneously from the Near East to Africa by demic diffusion—in other words, by a migration of food-producing peoples. The evi-dence presented by Wetterstrom (1993) does not support this latter suggestion, however, and indicates that early African farmers in the Fayum initially incorpo-rated Near Eastern domesticates into an existing indigenous foraging strategy and only over time developed a dependence on horticulture. In conclusion, the crucial linguistic finding is that the three deepest clades of the Afro-Asiatic family are localized in Eritrea and Ethiopia. All the other lan-guages of the family outside that region belong to subclades of just one of those deep clades. This kind of cladistic distribution is a basic criterion of the genetic argument for the genetic lineage origins well understood by geneticists. It applies to linguistic history as well. [b]Our results also point to a less ancient western African gene flow to Tunisia involving haplogroups L2a and L3b. Thus the sub-Saharan contribution to north-ern Africa starting from the east would have taken place before the Neolithic. The western African contribution to North Africa should have occurred before the Sahara’s formation (15,000 BP). It seems likely that an expansion would have taken place in the Sahel zone starting about the time of a gradual climatic return to wetter conditions, when the Senegal River cut through the dunes (Burke et al. 1971). For subhaplogroup L2a1 (data not shown) we found some haplotypes that the Tunisian Berbers shared with Mauritanians and western sub-Saharan popula-tions speaking a Niger-Congo language (studied by Salas et al. 2002). This sug-gests that the people who brought these markers to the Berber populations most likely came from West African populations that spoke languages belonging to the Niger-Congo family when the Sahara became drier. However, this contribution of West African haplotypes and of other haplotypes, such as those belonging to haplogroup L1b1, could have been introduced to North Africa more recently.Indeed, this West African contribution was difficult to date, because few haplotypes belonging to western African haplogroups have been observed, most of them being divergent. This result can be interpreted in different ways.[/b] Ancient western African mtDNA contributions could have disappeared from North Africa as a result of recent flows, or the situation observed now could be the result of a strong drift effect on ancient western African lineages, particularly those belong-ing to haplogroups L2a and L3b. A strong Iberian gene flow may have contrib-uted to the decrease in African haplogroups. Indeed, most of the older hypotheses about North African population settlement used to suppose an Iberian or an east-ern origin. The dates for subhaplogroups H1 and H3 (13,000 and 10,000 years, respectively) in Iberian and North African populations allow for this possibility. Kefi et al.’s (2005) data on ancient DNA could be viewed as being in agreement with such a presence in North Africa in ancient times (about 15,000–6,000 years ago) and with the fact that the North African populations are considered by most scholars as having their closest relations with European and Asian populations (Cherni et al. 2008; Ennafaa et al. 2009; Kefi et al. 2005; Rando et al. 1998). How-ever, considering the general understanding nowadays that human settlement of the rest of the world emerged from eastern northern Africa less than 50,000 years ago, a better explanation of these haplogroups might be that their frequencies re-flect the original modern human population of these parts of Africa as much as or more than intrusions from outside the continent. The ways that gene frequencies may increase or decrease based on adaptive selection, gene flow, and/or social processes is under study and would benefit from the results of studies on autoso-mal and Y-chromosome markers.Since the end of the extreme Saharan desiccation, lasting from before 25,000 years ago up to about 15,000 years ago, the Sahara has had post- and pre-Holocene cyclical climatic changes (Street and Grove 1976), and corresponding increases and decreases in population are probable. Wetter phases with better hab-itats perhaps allowed for increased colonization and gene and cultural exchange. Desiccation would have encouraged the emigration and segmentation of popu-lations, with resultant genetic consequences secondary to drift producing more variation. During the last glacial period, the Sahara was even bigger than it is today, extending south beyond its current boundaries (Ehret 2002). About 13,000 years ago, large parts of the Sahara were as dry as the desert is now (White and Mattingly 2006). The end of the glacial period brought more rain to the Sahara, especially from about 8500 to 6000 BC (Fezzan Project 2006). By around 3400 BC, the monsoon retreated south to approximately where it is today, leading to the gradual desertification of the region (Kröpelin 2008). Thus the Sahara, through its cyclical environmental changes, might be seen as a microevolutionary “proces-sor” and/or “pump” of African people that “ejected” groups to the circum-Saharan regions in times of increasing aridity. Indeed, it must be noted that the high frequencies of cDe, P, and V antigens and low frequencies of FY antigens in some Berber-speaking groups (Chamla 1980; Mourant et al. 1976) indicate affinities with tropical Africans. These data may indicate recent or ancient gene flow from sub-Saharan Africa, a common im-mediate pre-Holocene ancestral group, or chance resemblance. Our findings are in accordance with other studies on Y-chromosome mark-ers that have shown that the predominant Y-chromosome lineage in Berber com-munities is the subhaplogroup E1b1b1b (E-M81), which emerged in Africa, is specific to North African populations, and is almost absent in Europe, except in Iberia (Spain and Portugal) and Sicily. Molecular studies on the Y chromosome in North Africa are interpreted as indicating that the southern part of Africa, namely, the Horn/East Africa, was a major source of population in the Nile Valley and northwest Africa after the Last Glacial Maximum, with some migration into the Near East and southern Europe (Bosch et al. 2001; Underhill et al. 2001). Hence, contrary to the suggestion that mtDNA haplogroups were intro-duced mostly from Iberia, it seems that Y-chromosome markers have an eastern African origin with an ancient local evolution in North Africa. These observa-tions are in agreement with the proposal that the ancient communities ancestral in language to more recent Berber communities absorbed a lot of females from the existing pre-Holocene populations. This would indicate that the North Afri-can populations arose from admixture rather than from local evolution, leading to an intermediate genetic structure between eastern sub-Saharan Africans and Eurasians. Rock paintings in North Africa that show people of different pheno-types living together are a strong argument for our hypothesis (Hachid 1982, 1992, 1998).In conclusion, our findings parallel the more recent findings of both archae-ology and linguistics on the prehistory of Africa. The present study suggests that sub-Saharan contributions to North Africa have experienced several complex pop-ulation processes after the occupation of the region by anatomically modern hu-mans. Our results reveal that Berber speakers have a foundational biogeographic root in Africa and that deep African lineages have continued to evolve in supra-Saharan Africa [IMG]https://i.imgbox.com/X2EaG8bH.jpg[/IMG] _______________________________ [b]KESRA[/b] Kesra is a Berber village of the center-west, the highest of Tunisia with 1100 meters of altitude, famous for its megalithic monuments, its cascade of water and its stairs carved in the rock At a distance of 160 kms from Tunis and 120 kms from Kairouan, it is attached to the governorate of Siliana. It has about 2500 inhabitants. Kesra is the only ancient settlement in the area to survive. Historically, it played an important role. Exceptional architecture The stepped streets, the emblem of the village, date from Roman times, and it is not uncommon To find Punic and Latin inscriptions on the stones of the walls of the houses. The village contains megalithic monuments, some of which have retained their cover in large slabs, as well as tombs dug in the rock. The other Byzantine monuments were built with ancient materials, such as a quadrangular fortress of the Justinian period, ramparts and a tower. Also worth seeing is the zaouia of Sidi Ameur which is accessed by stairs cut in the rock. The Heritage Museum Kesra has a magnificent museum with three main themes: . Popular traditions and female artisan work (pottery, weaving) VIDEO: https://www.youtube.com/watch?v=cFBi7TPd0IY&t=48s [/QB][/QUOTE]
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