août 2017
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info:eu-repo/semantics/altIdentifier/doi/10.1016/j.quascirev.2017.06.025
L. Bremond et al., « Five thousand years of tropical lake sediment DNA records from Benin », HALSHS : archive ouverte en Sciences de l’Homme et de la Société, ID : 10.1016/j.quascirev.2017.06.025
Until now, sedimentary DNA (sedDNA) studies have only focused on cold and temperate regions wereDNA is relatively well preserved. Consequently, the tropics, where vegetation is hyperdiverse and naturalarchives are rare, have been neglected and deserve attention. In this study, we used next-generationsequencing to barcode sedDNA from Lake Sele, localized in the tropical lowlands of Benin (Africa), andcompared the taxonomic diversity detected by DNA analyses with pollen assemblages. Plant sedDNA wassuccessfully amplified from 33 of the 34 successfully extracted samples. In total, 43 taxa were identifiedalong the 5000 years spanned by the sediment: 22 taxa were identified at the family level and 21 at thegenus level. The plant diversity recovered through sedDNA from Lake Sele showed a specific local signaland limited overlapping with pollen. Introduced plants, grown and cultivated close to the water, such assweet potato, were also well recorded by sedDNA. It appears, therefore, to be a promising approach tostudying past diversity in tropical regions, and could help in tracking the introduction and history ofagriculture. This is the first time this method has been used in the field of domestication and disseminationof several specific crops, and the results are very encouraging.