Archaeobiogeography of extinct rice rats (Oryzomyini) in the Lesser Antilles during the Ceramic Age (500 BCE–1500 CE)

Abstract

During the Ceramic Age (500 BCE–1500 CE), Lesser Antilles rice rats (Tribe Oryzomyini) made up a significant portion of the diet of Caribbean islanders. Archaeological excavations across the archipelago resulted to the discovery of large quantities of remains from to these now extinct taxa. It offers a unique opportunity to investigate the past biogeography of this taxon of high cultural and ecological importance. We have studied 1140 first lower molars originating from 40 archaeological sites across eleven islands of the Lesser Antilles archipelago using two-dimensional geometric morphometric approaches to establish spatiotemporal patterns relying on phenotypic variations. This study identified three morphological groups, present in all chrono-cultural periods, that were geographically restricted and consistent with published ancient mitochondrial DNA clusters. These three geographically-separate groups likely represent three distinct genera of rice rats. The first group includes specimens from the North of the archipelago (Saint-Martin, Saba, Saint-Eustatius, Saint-Kitts, and Nevis) and likely referable to as Pennatomys sp.; the second, occurring in the South (Martinique), is assigned to Megalomys desmarestii; and the third corresponds to specimens from the center of the Lesser Antilles (Antigua, Barbuda, Marie-Galante, and Guadeloupe) and likely corresponds to Antillomys sp. These oryzomyine morphotypes are present during all studied periods and support an older presence of these rodents in the region. Our results are congruent with ancient DNA studies that favor the hypothesis of a natural introduction of the group in the archipelago before settlement of human populations. Moreover, the observed phenotypic homogeneity and stability over the 2000 years of Pre-Columbian occupation suggests that rice rats were not part of long-distance inter-island exchanges by humans. Instead, rice rat human consumption was likely based on in-situ hunting of local populations.

Paleodietary reconstruction of endemic rodents from the precolumbian Dominican Republic: Discriminating wild feeding behavior from diets linked to human niche construction activities

“…In the Lesser Antilles, there is some evidence to suggest that rice rats ( Oryzomys spp.) may have also been introduced either intentionally or unintentionally to new island environments and likely served as an important food source in some islands that were relatively depauperate of other terrestrial fauna (Brace et al, 2015 ; Durocher et al, 2021 ). It is probable that these species served similar roles as hutias did in the Greater Antilles.…”

Defining Fragmentation Patterns of Archaeological Bone Remains without Typologies: A Landmark-Based Approach on Rodent Mandibula

“…Specimens originate from 17 Lesser Antilleans islands and 45 archaeological sites (Table S1.1). The mandibular fragments studied originate from the same archaeological contexts as the teeth studied elsewhere [34]. Specimens are housed in the collections of the Regional Service of Archaeology (Service Régional de l'Archéologie, Direction des Affaires Culturelles (DAC)) of Guadeloupe and Martinique, at the Muséum national d'Histoire naturelle de Paris (MNHN, France), and at the Florida Museum of Natural History (FLMNH, USA).…”