1 Citation 387 Views 26 Downloads
Human-mediated biological exchange has had global social and ecological
impacts. In sub-Saharan Africa, several domestic and commensal animals
were introduced from Asia in the pre-modern period; however, the timing
and nature of these introductions remain contentious. One model supports
introduction to the eastern African coast after the mid-first millennium
CE, while another posits introduction dating back to 3000 BCE. These
distinct scenarios have implications for understanding the emergence of
long-distance maritime connectivity, and the ecological and economic
impacts of introduced species. Resolution of this longstanding debate
requires new efforts, given the lack of well-dated fauna from
high-precision excavations, and ambiguous osteomorphological
identifications. We analysed faunal remains from 22 eastern African sites
spanning a wide geographic and chronological range, and applied
biomolecular techniques to confirm identifications of two Asian taxa:
domestic chicken (Gallus gallus) and black rat (Rattus rattus). Our
approach included ancient DNA (aDNA) analysis aided by BLAST-based
bioinformatics, Zooarchaeology by Mass Spectrometry (ZooMS) collagen
fingerprinting, and direct AMS (accelerator mass spectrometry) radiocarbon
dating. Our results support a late, mid-first millennium CE introduction
of these species. We discuss the implications of our findings for models
of biological exchange, and emphasize the applicability of our approach to
tropical areas with poor bone preservation.
387 views reported since publication in 2018.