DateBack, a digital open access repository of archaeobotanical data for reconstructing date palm history

The date palm (Phoenix dactyliferaL.) has been a cornerstone of oasis agrosystems in West Asia and North Africa for millenia, yet the timeline and processes of its domestication and spread remain poorly documented. Archaeobotanical remains provide critical insights into its cultivation history, but no comprehensive review or dedicated platform currently exists to synthesize and analyze these data.

To address this gap, we conducted an extensive literature review and developedDateBack(<ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://cloudapps.france-bioinformatique.fr/dateback">https://cloudapps.france-bioinformatique.fr/dateback</ext-link>), a digital open access repository of archaeobotanical remains ofPhoenixspp. In its first version,DateBackrecords macroremains (e.g., seeds, fruits, stems, petioles) from prehistoric to Late Antiquity contexts in Southwest and South Asia.

We assembled 140 entries from 99 archaeological sites across 110 references, along with a separate table of 55 radiocarbon-dated entries from 17 sites, refining chronological assessments. Most entries comprise charred seeds (55.7%), with a smaller proportion of charred vegetative parts or desiccated remains. Our findings highlight regional disparities in remain distribution, concentrated in the Levant and Gulf, while Saudi Arabia and southern Iran are underrepresented, and in data reliability, particularly dating resolution, complicating the reconstruction of date cultivation history. Our evidence shows that the earliest securely dated remains, indicating date consumption, appear in the Gulf around 5000 BCE, while cultivation emerges later, first in southern Mesopotamia and the northern Gulf in the 4^thmillennium BCE, then in eastern Arabia and the Indus Valley in the 3^rdmillennium BCE. The Levant presents challenges, with numerous presumed early finds but significant uncertainties, with secure evidence of cultivation only appearing by the late 2^ndmillennium BCE, as in northwestern Arabia, while in the southern Arabian Peninsula, it is not attested until the 1^stmillennium BCE.

By compiling and standardizing archaeobotanical data,DateBackfacilitates advanced spatiotemporal analyses and supports additional archaeobotany-based research including ancient DNA studies. Moreover, the platform is dynamic, scalable, and collaborative, enhancing data integration and refinement, with future expansions planned to include additional periods (Islamic era and beyond), geographic regions (North Africa), and new types of evidence, such as plant microremains and iconography.