RT Journal Article SR Electronic T1 The date palm (Phoenix dactylifera L.) in Siwa oasis (Egypt): How ethnographic, morphometric, and genetic analyses together explain the local agrobiodiversity JF bioRxiv FD Cold Spring Harbor Laboratory SP 122846 DO 10.1101/122846 A1 Vincent Battesti A1 Muriel Gros-Balthazard A1 Clémence Ogéron A1 Sarah Ivorra A1 Jean-Frédéric Terral A1 Claire Newton YR 2017 UL http://biorxiv.org/content/early/2017/03/31/122846.abstract AB The agrobiodiversity of the Siwa oasis (in Egypt), located at the crossroads of ancient Trans-Saharan routes, is evaluated in this article focusing on the date palm (Phoenix dactylifera L.), the oasis “ecosystem engineer”. This assessment confronts different ontologies: diversity as expressed and maintained by the folk categorization system of the Siwa inhabitants (through the results of an ethnographical analysis) and diversity described by genetic sciences and a morphometric tool based on the size and geometry of the seeds. This work is also an opportunity to evaluate this tool intended for archaeobotany. Beyond a simple instrumentalization of one discipline by another, this study offers a space of mutual enrichment: on the relative importance of the feral and cultivated date palms, the local relevance of the concept of “cultivar” and the confirmation of the existence of “ethnovarieties”.