An Evolutionary Approach to the History of Barley (Hordeum vulgare) Cultivation in the Canary Islands

Abstract

The Canary Islands are an archipelago that lies about 100 km west of North Africa. Barley (Hordeum vulgare) has been continuously cultivated since the colonization of the islands. To investigate the agricultural history of the islands, the DNA from multiple individuals of six extant landraces of barley was sequenced, and the resulting data were analyzed with ABC modeling. Estimates of separation times of barley populations on the different islands and the mainland were congruent with archaeological dating of the earliest settlements on the islands. The results of the genetic analyses were consistent with the continuous cultivation of barley on Lanzarote island since it was first colonized, but suggested cultivation was carried out at a smaller scale than on Gran Canaria and Tenerife. Contrary to archaeological evidence and early written historical sources, the genetic analyses suggest that barley was cultivated on a larger scale on Tenerife than on Gran Canaria. The genetic analysis of contemporary barley added support to the dating of the colonization of the islands and pointed to the need for more archaeological data concerning barley cultivation on Tenerife.

Who, Why, When, and Where From? The Peopling of the Canary Islands and the Challenges of Archaeometry

“…The absence of human remains for the eastern islands is problematic, considering the stepping-stone model assumes this region would have been occupied first (Atoche-Peña & del-Arco-Aguilar, 2023), and should therefore provide the oldest human genotypes. Interestingly, genomic data from extant barley seeds indicates that an older grain strain was grown in Lanzarote and exchanged between eastern and western islands (Hagenblad & Morales, 2020), thus supporting the stepping-stone model.…”

Characterization of the complete chloroplast genome of Hordeum vulgare L. var. trifurcatum with phylogenetic analysis

“…The genus Hordeum comprises more than 30 species. Some varieties are also found in this genus (Malysheva-Otto et al 2006;Forsberg et al 2019;Hagenblad and Morales 2020;Kumar et al 2020). Organelle genomes have been widely used in study of taxonomy, evolution and genetics (Wang et al 2016;Yang et al 2019;Wang et al 2020;Li, He, et al 2020).…”

Archaeological Research in the Canary Islands: Island Archaeology off Africa’s Atlantic Coast

“…The archaeobotanical picture of a general decline in crop diversity across the islands with time supports this. It suggests that Fuerteventura and Lanzarote quickly became isolated from the rest of the group, but that seed exchange may have persisted longer between Gran Canaria and Tenerife in the archipelago's center (Hagenblad and Morales 2020). Analyses of human aDNA from La Gomera and El Hierro further suggest that the populations of individual islands experienced long-term isolation, compounded genetically by strong founder effects in small colonizing groups (Calderón Ordóñez et al 2017;Fregel et al 2015).…”