Marine Durocher
email: marine.durocher@mnhn.fr

Violaine Nicolas

Sophia Perdikaris

Dominique Bonnissent

Gwenola Robert

Karyne Debue

Allowen Evin

Sandrine Grouard

Archaeobiogeography of extinct rice rats (Oryzomyini) in the Lesser Antilles

Keywords:

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INTRODUCTION

The Lesser Antilles are an oceanic archipelago in the Caribbean, located between two biogeographic features, the Anegada passage off the Anguilla bank [START_REF] Jany | Geological interpretation of combined Seabeam, Gloria and seismic data from Anegada Passage (Virgin Islands, north Caribbean)[END_REF], and Koopman's Line off the Grenada Bank [START_REF] Genoways | Bats of the Grenadine Islands, West Indies, and placement of Koopman's line[END_REF] (Fig. 1). The Lesser Antilles show a low diversity of terrestrial organisms associated with a high rate of endemism common to many island ecosystems (e.g. [START_REF] Baker | Zoogeography of Antillean Bats[END_REF][START_REF] Bond | A Field Guide to the Birds of the West Indies[END_REF][START_REF] Hedges | Distribution patterns of amphibians in the West Indies. Patterns of distribution of amphibians: a global perspective[END_REF][START_REF] Ricklefs | The Causes of Evolutionary Radiations in Archipelagoes: Passerine Birds in the Lesser Antilles[END_REF] which are profoundly influenced by both modern and past human activity [START_REF] Whittaker | Island biogeography: ecology, evolution, and conservation[END_REF]. The first attested human settlement in the Lesser Antilles dates to the 4 th millennium BCE [START_REF] Bonnissent | Archéoécologie des sociétés insulaires des Petites Antilles au Mésoindien: l'enjeu des ressources à Saint-Martin[END_REF] in Saint-Martin.

Archaeological records confirm the ancient introduction and translocation of continental plants and animals that are still present today, including manioc (Manihot exculenta), maize (Zea mays), papaya (Carica papaya) [START_REF] Newsom | On land and sea: Native American uses of biological resources in the West Indies[END_REF][START_REF] Jiménez | La temprana introducción y uso de algunas plantas domésticas, silvestres y cultivos en las Antillas precolombinas. Una primera revaloración desde la perspectiva del 'arcaico'de Vieques y Puerto Rico[END_REF], dogs (Canis familiaris), and agouti (Dasyprocta sp.) [START_REF] Bonnissent | Archéologie précolombienne de l'île de Saint-Martin, Petites Antilles (3300 BC-1600 AD)[END_REF][START_REF] Giovas | New records for prehistoric introduction of Neotropical mammals to the West Indies: evidence from Carriacou, Lesser Antilles[END_REF][START_REF] Giovas | Sr and Pb isotopic investigation of mammal introductions: Pre-Columbian zoogeographic records from the Lesser Antilles, West Indies[END_REF]Wing, 2001a). Lesser Antillean rice rats (tribe Oryzomyini) are considered to be endemic to the archipelago, as the timing of their arrival in this area has been estimated via molecular clock analysis to the Late Miocene (6. 814-6.303 Mya -Brace, Turvey, Weksler, Hoogland, & Barnes, 2015). However, the oldest secure evidence of rice rats recovered from the paleontological record is contemporaneous with the earliest human occupations of the archipelago [START_REF] Steadman | Fossil vertebrates from Antigua, Lesser Antilles: Evidence for late Holocene human-caused extinctions in the West Indies[END_REF]. Rice rats are abundant in archaeological assemblages and show clear evidence of consumption (cutting and burning marks) [START_REF] Grouard | Modes de vie des Précolombiens des Antilles françaises. Synthèse des données archéozoologiques[END_REF], though are now extinct across the Lesser Antilles, with the last living specimen recorded during the mid-late 19 th century [START_REF] Allen | Extinct and Vanishing mammals of the Western Hemisphere[END_REF][START_REF] Ray | The oryzomyine rodents of the Antillean subregion: a thesis[END_REF]. Traditional reasons for small mammal extinction on islands include the introduction of competing species [START_REF] Macphee | Requiem Aeternam. Extinctions in near time[END_REF] such as rats (Rattus rattus and R. norvegicus) or new predators like the cat (Felis silvestris) [START_REF] Henderson | Consequences of predator introductions and habitat destruction on amphibians and reptiles in the post-Columbus West Indies[END_REF], the Small Indian mongoose (Herperstidae, Urva auropunctata) [START_REF] Grouard | Subsistance, systèmes techniques et gestion territoriale en milieu insulaire antillais précolombien: exploitation des vertébrés et des crustacés aux époques Saladoïdes et Troumassoïdes de Guadeloupe[END_REF][START_REF] Henderson | Consequences of predator introductions and habitat destruction on amphibians and reptiles in the post-Columbus West Indies[END_REF][START_REF] Horst | The mongoose in the West Indies: the biogeography and population biology of an introduced species[END_REF] and the racoon (Procyonidae, Procyon lotor) [START_REF] Louppe | Occupancy modelling of two invasive carnivores in two Caribbean islands: implications for insular ecosystems[END_REF], or overhunting [START_REF] Ray | The oryzomyine rodents of the Antillean subregion: a thesis[END_REF][START_REF] Steadman | Fossil vertebrates from Antigua, Lesser Antilles: Evidence for late Holocene human-caused extinctions in the West Indies[END_REF][START_REF] Trouessart | Note sur le rat musqué ("Mus pilorides") des Antilles, type du sousgenre" Megalomys"(Trt) et la place de ce sous-genre dans le groupe des rats américains ou" Hesperomyeae[END_REF], along with the transformation of the landscapes and deforestation [START_REF] Boudadi-Maligne | Evidence for historical human-induced extinctions of vertebrate species on La Désirade (French West Indies)[END_REF]). Yet the specific causes of rice rat extinction in the Lesser Antilles still remains unclear.

Pre-Columbian societies relied primarily on marine resources such as fish and mollusks [START_REF] Grouard | Caribbean archaeozoology. Current Advances in Latin-American Archaeozoology[END_REF][START_REF] Wing | Prehistoric ceramic age adaptation to varying diversity of animal resources along the West Indian archipelago[END_REF] but terrestrial mammals, including oryzomyines, were also consumed as evidenced by the presence of butchery and burning marks on recovered remains [START_REF] Grouard | Variation des stratégies de subsistance des Précolombiens à Hope Estate, Saint-Martin (Petites Antilles), d'après l'analyse des restes des petits vertébrés[END_REF][START_REF] Grouard | Caribbean archaeozoology. Current Advances in Latin-American Archaeozoology[END_REF][START_REF] Newsom | On land and sea: Native American uses of biological resources in the West Indies[END_REF]Wing, 2001bWing, , 2001a)). Rice rats were an important part of the human diet throughout the Ceramic Age. Analysis of zooarchaeological collection from the site of Hope Estate (Saint-Martin) show that rice rats comprise 54% of the total number of all identified vertebrates (NMI=748/1,384; [START_REF] Grouard | Variation des stratégies de subsistance des Précolombiens à Hope Estate, Saint-Martin (Petites Antilles), d'après l'analyse des restes des petits vertébrés[END_REF]. Extensive evidence for anthropic inter-island exchange in the Lesser Antilles has been evidenced for e.g. dogs, humans, raw materials, and artefacts (i.e. [START_REF] Bonnissent | Archéologie précolombienne de l'île de Saint-Martin, Petites Antilles (3300 BC-1600 AD)[END_REF][START_REF] Bonnissent (dir | Les gisements précolombiens de la Baie Orientale: campements du Mésoindien et du Néoindien sur l'île de Saint-Martin (Petites Antilles)[END_REF][START_REF] Fitzpatrick | The pre-Columbian Caribbean: Colonization, population dispersal, and island adaptations[END_REF][START_REF] Hofman | Archipelagic resource procurement and mobility in the northern Lesser Antilles: the view from a 3000-year-old tropical forest campsite on Saba[END_REF][START_REF] Hofman | Island rhythms: the web of social relationships and interaction networks in the Lesser Antillean archipelago between 400 BC and AD 1492[END_REF][START_REF] Hofman | Attractive ideas, desirable goods: examining the Late Ceramic Age relationships between Greater and Lesser Antillean societies[END_REF][START_REF] Hofman | Unravelling the multi-scale networks of mobility and exchange in the pre-colonial circum-Caribbean. Communities in contact: Essays in archaeology, ethnohistory and ethnography of the Amerindian Circum-Caribbean[END_REF][START_REF] Knippenberg | Stone artefact production and exchange among the Lesser Antilles[END_REF][START_REF] Laffoon | Oxygen and carbon isotope analysis of human dental enamel from the Caribbean: implications for investigating individual origins[END_REF][START_REF] Laffoon | The movement and exchange of dogs in the prehistoric Caribbean: An isotopic investigation[END_REF][START_REF] Laffoon | Human dietary assessment in the Pre-colonial Lesser Antilles: New stable isotope evidence from Lavoutte, Saint Lucia[END_REF][START_REF] Stouvenot | Matières premières lithiques des sites mésoindien et néoindien de la Baie Orientale à Saint-Martin (Petites Antilles)[END_REF]. It is still unclear whether rice rats were part of this network. Anthropic translocation has been proposed for the group (LeFebvre and deFrance, 2014) and examplified by the presence of South American rice rats of the genus Zygodontomys in the island of Carriacou [START_REF] Giovas | Pre-Columbian Amerindian Lifeways at the Sabazan Site, Carriacou, West Indies[END_REF][START_REF] Mistretta | Grenada's extinct rice rats (Oryzomyini): Zooarchaeological evidence for taxonomic diversity[END_REF].

Rodents have colonized a remarkable number of islands worldwide, either by natural dispersal (e.g. [START_REF] Fabre | A new genus of rodent from Wallacea (Rodentia: Muridae: Murinae: Rattini), and its implication for biogeography and Indo-Pacific Rattini systematics[END_REF][START_REF] Jansa | The pattern and timing of diversification of Philippine endemic rodents: evidence from mitochondrial and nuclear gene sequences[END_REF], as stowaway like the black rat (Rattus rattus; [START_REF] Macphee | Requiem Aeternam. Extinctions in near time[END_REF][START_REF] Vigne | Small mammal fossil assemblages as indicators of environmental change in northern Corsica during the last 2500 years[END_REF] or intentional transportation like the domestic guinea pig (Cavia porcellus; [START_REF] Kimura | Origin of pre-Columbian guinea pigs from Caribbean archeological sites revealed through genetic analysis[END_REF][START_REF] Lefebvre | Guinea Pigs in the Pre-Columbian West Indies[END_REF][START_REF] Lord | Complete mitogenomes of ancient Caribbean Guinea pigs (Cavia porcellus)[END_REF]. Morphological similarities between rodent populations can be used to explore the type of dispersal (e.g. [START_REF] Cucchi | The changing pace of insular life: 5000 years of microevolution in the Orkney vole (Microtus arvalis orcadensis)[END_REF][START_REF] Lefebvre | Bahamian hutia (Geocapromys ingrahami) in the Lucayan Realm: pre-Columbian exploitation and translocation[END_REF] along with the impact of environmental factors on their diversity (e.g. [START_REF] Maestri | Geometric morphometrics meets metacommunity ecology: environment and lineage distribution affects spatial variation in shape[END_REF].

In this study we have used tooth identification as the basis of our analysis. Teeth have an advantage over other skeletal elements in that they are often well preserved, are recovered in large numbers in the archaeological record and known to be taxonomically informative [START_REF] Cucchi | Le commensalisme de la souris et les sociétés néolithiques méditerranéennes[END_REF][START_REF] Darviche | Mus spretus et M. musculus (Rodentia, Mammalia) en zone méditerranéenne: différenciation biométrique et morphologique: application à des fossiles marocains pléistocènes/Mus spretus and M. musculus (Rodentia, Mammalia) in the Mediterranean zone: biometric and morphological differentiation: application to Pleistocene Moroccan fossils[END_REF][START_REF] Darviche | Critères de différenciation morphologique et biométrique de deux espèces de souris sympatriques: Mus spretus et Mus musculus domesticus[END_REF][START_REF] Renaud | Fourier analysis applied to Stephanomys (Rodentia, Muridae) molars: nonprogressive evolutionary pattern in a gradual lineage[END_REF][START_REF] Van Dam | Stephanodonty in fossil murids[END_REF].

Consequently, teeth, especially their size and shape have been used to study past rodent populations and their relationship with human societies (e.g. [START_REF] Cucchi | The changing pace of insular life: 5000 years of microevolution in the Orkney vole (Microtus arvalis orcadensis)[END_REF]Hulme-Beaman et al., 2018b;[START_REF] Valenzuela-Lamas | House mouse dispersal in Iron Age Spain: a geometric morphometrics appraisal[END_REF].

Because Lesser Antilles rice rats have no direct modern relatives and because morphological evolution of insular populations can happen very fast [START_REF] Millien | Morphological evolution is accelerated among island mammals[END_REF] eventually leading to inter-island radiation (e.g. [START_REF] Kadmon | Integrating the effects of area, isolation, and habitat heterogeneity on species diversity: a unification of island biogeography and niche theory[END_REF], the current systematic and taxonomy of the group is still not fully established. Three genera are currently recognized in the Lesser Antilles archipelago [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF][START_REF] Machado | Phylogeny and biogeography of tetralophodont rodents of the tribe Oryzomyini (Cricetidae: Sigmodontinae)[END_REF] (Fig. 1): Pennatomys has been described in the North of the archipelago (Saint-Eustatius, Saint-Kitts and Nevis) [START_REF] Turvey | Taxonomy, phylogeny, and diversity of the extinct Lesser Antillean rice rats (Sigmodontinae: Oryzomyini), with description of a new genus and species[END_REF], Megalomys [START_REF] Trouessart | Note sur le rat musqué ("Mus pilorides") des Antilles, type du sousgenre" Megalomys"(Trt) et la place de ce sous-genre dans le groupe des rats américains ou" Hesperomyeae[END_REF] in the South (Martinique, Saint-Lucia and Barbados) [START_REF] Major | The musk-rat of Santa Lucia (Antilles)[END_REF][START_REF] Friant | Notes anatomiques sur les Megalomys des Antilles[END_REF][START_REF] Miljutin | Notes on the external morphology, ecology, and origin of Megalomys desmarestii (Sigmodontinae, Cricetidae, Rodentia), The extinct giant rat of Martinique Island, Lesser Antilles[END_REF], and Antillomys [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF] in the center (Guadeloupe, Antigua and Barbuda) [START_REF] Barbotin | Les sites archéologiques de Marie-Galante (Guadeloupe)[END_REF][START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF][START_REF] Hopwood | XLVI.-A fossil rice-rat from the Pleistocene of Barbuda[END_REF][START_REF] Pregill | Late Quaternary vertebrate Faunas of the Lesser Antilles: Historical components of Caribeean Biogeography[END_REF]. These three genera are supported by high genetic divergence (560 bp of the Cytochrome b gene) and according to ancient genetic data Megalomys and Pennatomys are sister clades, only distantly related to the genus Antillomys [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF]. The present study aims to assess the archaeobiogeography of the oryzomyines taxa in the Lesser Antilles during the Ceramic Age and explore whether spatio-temporal variation in their morphology can be explained through human translocation. Results were compared to published ancient DNA clusters in order to gain in the understanding on the group taxonomy.

<Figure 1>

MATERIALS

Chrono-cultural division

The pre-Columbian archaeology of the Lesser Antilles is divided into two main periods: the Early and Late Ceramic Ages, each further divided into an early and a late phase. The Early Ceramic Age corresponds to the Saladoid cultures and it is divided into an early phase A (ECA) dating from c. 500 BCE to 400 CE (Early Cedrosan Saladoid and Huecan Saladoid), and a late phase B (ECB) from c. 400 to 600/800 CE (modified Cedrosan Saladoid, Late Saladoid, and Saladoid with Barrancoid influences) [START_REF] Bérard | Pre-Columbian Antillean civilizations in an archipelagic perspective[END_REF][START_REF] Fitzpatrick | The pre-Columbian Caribbean: Colonization, population dispersal, and island adaptations[END_REF][START_REF] Hofman | Island rhythms: the web of social relationships and interaction networks in the Lesser Antillean archipelago between 400 BC and AD 1492[END_REF][START_REF] Hofman | Attractive ideas, desirable goods: examining the Late Ceramic Age relationships between Greater and Lesser Antillean societies[END_REF]. The Late Ceramic Age corresponds to the Troumassoid cultures and is divided into an A phase (LCA) dated from 600/800 to c. 1200 CE, and a B phase (LCB) dated from c. 1200 to 1500 CE. Contrary to the Early Ceramic, the two phases of Late Ceramic were characterized by a geographic division between the North and the South of the archipelago [START_REF] Crock | Inter-island exchange, settlement hierarchy, and a Tainorelated chiefdom on the Anguilla Bank, Northern Lesser Antilles. Late Ceramic Age Societies in the Eastern Caribbean[END_REF][START_REF] Mol | Costly Giving, Giving Guaízas: Towards an Organic Model of the Exchange of Social Valuables in the Late Ceramic Age Caribbean[END_REF][START_REF] Rouse | Excavations at the Indian Creek Site[END_REF][START_REF] Siegel | Early ceramic population lifeways and adaptive strategies in the Caribbean[END_REF]. The LCA is characterized by the Northern Troumassan Troumassoid and the Southern Suazan Troumassoid, while the LCB correspond to the Marmoran Troumassoid in the North and Troumassan Troumassoid in the South.

Studied specimens

A total of 1140 archaeological first lower molars (M1, either isolated or enclosed in the mandible) belonging to adult specimens with limited wear were analyzed. When teeth were not found isolated, only hemi-mandibles were recovered and could not be left and right paired to form complete jaws based on tooth wear abrasion or stratigraphic information, as a consequence it is possible that both the right and left M1 of some specimens were included in the analyses. Specimens originated from 40 archaeological sites spanning across the pre-Columbian Ceramic Age in eleven islands throughout the archipelago (Fig. 1; Table 1). Specimens were assigned to chronological cultural phases based on primary publications and excavation reports, and according to investigators' opinion (Table 1; SI.1).

<Table 1>

METHODS

Morphometrics

Photographs of the occlusal view of the lower first molar were taken using a LEICA 76 APO macroscope and a non-distorting objective, with a 1.25x or 1.6x magnification and Leica Microsystem LAS software (V4.8). A sliding semi-landmark based geometric morphometric approach was employed to quantify the size and the shape of the teeth. On each photograph, the two-dimensional coordinates of one landmark, placed at the junction between the most posterior point of the metaconid and the external buccal edge of the tooth were recorded, along with 65 equidistant sliding semi-landmarks localized along the external edge of the tooth (recorded clockwise) (Fig. 2) using TPS Dig2 [START_REF] Rohlf | tpsDig-thin plate spline digitizer, version 1.40[END_REF]. All photographs and measurements were taken by the same person (M.D.). Coordinates were superimposed using a generalized Procrustes analysis (GPA) [START_REF] Goodall | Procrustes methods in the statistical analysis of shape revisited[END_REF][START_REF] Rohlf | Extensions of the Procrustes method for the optimal superimposition of landmarks[END_REF], with the semilandmarks allowed to slide following the Procrustes distance minimization criterion. Analyses of size were based on the log-transformed centroid size, and investigation of shape performed on the Procrustes residuals (coordinates after superimposition).

<Figure 2>

Statistics

Prior to analyses, the existence of size or shape clusters at each archaeological site, island, island bank, and overall was examined using a Gaussian Mixture Modelling for Model-Based Clustering (R package 'mclust, [START_REF] Scrucca | Genetic algorithms for subset selection in model-based clustering[END_REF]. This approach determines, based on a maximized loglikelihood approach, the number of clusters (i.e. groups) present in the dataset, without a priori knowledge. Centroid size differences between populations from different sites, periods, islands and island banks were tested with Kruskal-Wallis and Wilcoxon tests and visualized by boxplots.

In pairwise comparisons, p-values were adjusted using a Benjamini-Hochberg multicomparison procedure [START_REF] Benjamini | Controlling the false discovery rate: a practical and powerful approach to multiple testing[END_REF].

The shape variation was examined through the application of principal component analysis (PCA), before testing differences between groups through multivariate analysis of variance (MANOVA). Because of the large number of variables compared to the relatively low number of specimens per group, a dimensionality reduction of the data was performed [START_REF] Baylac | Fourier descriptors, Procrustes superimposition, and data dimensionality: an example of cranial shape analysis in modern human populations[END_REF][START_REF] Evin | The long and winding road: identifying pig domestication through molar size and shape[END_REF]. Canonical variate analysis (CVA) and MANOVAs were performed on the firsts PCA scores that maximized the between-group discrimination quantified by leave-one-out cross validation [START_REF] Baylac | Fourier descriptors, Procrustes superimposition, and data dimensionality: an example of cranial shape analysis in modern human populations[END_REF][START_REF] Dobigny | Geometric morphometrics, neural networks and diagnosis of sibling Taterillus species (Rodentia, Gerbillinae)[END_REF].

CVA was used to quantify and visualize the group differences [START_REF] Albrecht | Multivariate analysis and the study of form, with special reference to canonical variate analysis[END_REF][START_REF] Gittins | Canonical variate analysis[END_REF][START_REF] Russell | Canonical Variate Analysis. Data-driven Methods for Fault Detection and Diagnosis in Chemical Processes[END_REF]. The discrimination power of the CVA was quantified by the mean crossvalidation percentage (CVP) and the 90% confidence interval obtained from 100 CVAs performed on resampled same-size datasets [START_REF] Evin | The long and winding road: identifying pig domestication through molar size and shape[END_REF]. This approach randomly subsamples the largest groups to the size of the smallest group, thus removing effects of unbalanced sample size which is common and largely inevitable in bioarchaeology [START_REF] Evin | The long and winding road: identifying pig domestication through molar size and shape[END_REF].

Cross-validation percentages were calculated for size, shape and form (size+shape). In addition to CVA, phenotypic dissimilarity between groups were assessed using both Mahalanobis and Procrustes distances. Distances were computed only for groups of at least 10 specimens and the repeatability of the topologies was estimated by bootstrap with 1000 replicates. Procrustes distances between group mean shape was obtained following [START_REF] Nagorsen | Tempo and mode of evolutionary divergence in modern and Holocene Vancouver Island marmots (Marmota vancouverensis)(Mammalia, Rodentia)[END_REF] and Mahalanobis distances were obtained from resampled datasets with equal number of specimens per group. For both approaches the number of resampled specimens match the number of specimens in the smallest group. The majority-rule consensus and mean branch lengths topologies were computed as unrooted Neighbor-Joining (NJ) networks [START_REF] Friesen | Sympatric speciation by allochrony in a seabird[END_REF][START_REF] Saitou | The neighbor-joining method: a new method for reconstructing phylogenetic trees[END_REF] on which the percentage of trees in which each observed node grouping appeared has been reported (i.e. bootstrap supports). All analyses were performed in R version 3.5.3 (R Core Team, 2019), with the 'ape' [START_REF] Paradis | ape 5.0: an environment for modern phylogenetics and evolutionary analyses in R[END_REF], 'Morpho' [START_REF] Schlager | Morpho: Calculations and visualisations related to Geometric Morphometrics[END_REF] and 'Geomorph' [START_REF] Adams | Geomorph: Software for geometric morphometric analyses[END_REF] packages.

RESULTS

None of the clustering analysis on size and shape revealed the presence of multiple groups.

As a consequence, the composition of each archaeological site was considered homogeneous.

Despite the fact that the number of teeth per site and chrono-cultural period was maximized by including right and left teeth, statistical analyses were highly constrained by the number of specimens per site and chrono-cultural period. As a precaution, a subset of analyses were performed for teeth of only one side (left) of the mandible and provide congruent results though based on much less groups (for homogeneity groups with less than 10 specimens were excluded). Analyses performed in this study were constraint by available archaeological data which range from an island with only one site occupied during one period (e.g Saint-Kitts) to islands occupied during all periods on multiple sites (e.g. Martinique).

Main archaeobiogeographic pattern

Analysis of the populations from each site and each cultural time period revealed three geographically structured clusters (figs. 3 & 4). <Figure 3> <Figure 4 > Molar centroid size analysis revealed two main clusters, perfectly discriminated, with the specimens from the Northern islands (Saint-Martin, Saba, Saint-Eustatius, Saint-Kitts and Nevis) showing much smaller teeth than any other specimens from across the archipelago (Fig. 3).

Shape analysis revealed differences between the populations (F(46,2238)=105.91, p≤ 2.2e-16). While Procrustes distances do not provide a resolved network topology (most bootstrap values are < 50%) (SI.2), Mahalanobis networks (Fig. 4, SI.2) revealed three perfectly supported clusters (100% bootstrap values) that are geographically structured. The first cluster corresponds to the northern islands (Saint-Martin, Saba, Saint-Eustatius, Saint-Kitts and Nevis), the second to the central islands (Barbuda, Antigua, Grande-Terre and Basse-Terre of Guadeloupe, and Marie-Galante) while the third correspond the southern island of Martinique.

However, when working at the island scale (SI.2) the split between Martinique and the central islands is not supported, but because of the relatively long length of the Martinique branch and the high size differences between the two geographic clusters (Fig. 3) they were considered as valid morphometric and geographic entities. The paired leave-one-out cross validation between the three geographic clusters is high (94.4 %; CI: 92.9 -95.9 %) confirming their morphometrical distinction. Moreover, when molar form is analyzed, combining size and shape data, this percentage reaches 99.7 % (CI: 99.3 -100 %).

Regional spatio-temporal patterns

Variation within the three clusters was then investigated at different geographical and chronological scales by looking at the differences between island banks (during past low-stand sea levels occurrences), between islands and sites, and through the different cultural time periods.

The five northern Islands

Populations from the five northern islands differ in both size (X 2 =147.5, df=4, p≤ 2.2e-16; CVP=35%(CI:28.8-43.8%); SI.3.2) and shape (F(44-2528)=11.8, p≤2.2e-16; CVP=51.1% (CI:41.3-58.8%); SI.3.1-2) (Fig. 5). The island structuring of the populations observed in the networks (Fig. 4 & 5) is also evidenced by pairwise comparisons (SI.3.2). The differences between islands exceed the differences between cultural time periods despite the small number of populations available for comparison. Only Saint-Martin is represented by more than one period with sufficient specimens for a diachronic comparison. One site (Hope Estate) was occupied during the ECA and ECB, and the corresponding specimens differ only slightly in shape (F(4,517)=4, p=3e-3; CVP=55.7% (CI:50.5-59.9%)) and not in size (W=22975, p=0.3; CVP=49.1% (CI:46.8-53.2%)). On the other hand, differences between islands during the ECB are highly significant in both size (X 2 =106.3, df=3, p≤2.2e-16; CVP= 39.7% (CI:29.7-48.4%); SI.3.2) and shape (F(24-1533)=15.5, p≤2.2e-16; CVP= 57.8% (CI:40.9-65.7%); SI.3.1-2).

<Figure 5>

Martinique

In Martinique, the populations differ in both size (X 2 =19.5, df=5, p=0.0015; CVP= 23.5% CI:5.6-38.9%)) and shape (F(85,355)=2.2, p=4e-7; CVP=27.9% (CI:11.1-44.4%)). Specimens from the Early and Late Ceramic differ in shape (F(14,64)=3.9, p=8e-5; CVP=71.7% (CI:64.8-79.6%); SI.4.1-2), but not in size (W=707, p=1; CVP=35.2% (CI: 3.6-51.9%), SI.4.2). The specimens from the ECB populations do not differ in size (X 2 = 4, df=2, p=0.1) or shape (F(16,36)=1.7, p=0.1). During the LCB, there was no observed size difference, (W=257, p=0.94), but shape varied (F(8,38)=2.6, p=0.02; CVP=64.5% (CI:55.6-75%)).

The five Central islands

The populations from the central islands differ in both size (X 2 =105.4, df=4, p<2.2e-16; CVP=32.6% (CI:28.1-37.8%)) and shape (F(100,1536)=4.4, p≤2.2e-16; 44.7% (CI:38.5-51.2%)). Only populations from Barbuda and Guadeloupe Basse-Terre are clustered by islands (only one population was studied from Antigua) contrary to the populations from Grande-Terre and Marie-Galante (Fig. 6).

<Figure 6>

Specimens from the two islands of the Barbuda bank (Antigua and Barbuda) differ from each other in shape (F(7,61)=3.1, p=0.007; CVA=65.6% (CI:59.3-72.2%); SI.5.1) but not in size (W=454, p=0.2). Specimens from the three archeological sites from Antigua (SI.5.1-2), all attributed to the LCA, differ in shape (F(16,36)=2.1, p=0.03; CVA=41.4% (CI:22.2-66.7%)) but not in size (X 2 =1.49, df=2, p=0.47). On Barbuda, the specimens from the two sites (one ECA, one LCA) do not differ in their molar size (W=170, p-value=0.2) nor shape (F(3,38)=0.3, p=0.9).

Thirteen sites were analyzed from the Guadeloupe Bank (Basse-Terre + Grande-Terre, Table 1; SI.5.1-2). On average, specimens from Basse-Terre have larger molars than those from Grand-Terre (W=6398, p=5.4e-11, CVP=71.1% (CI:68.8-73.6%)) and differ slightly in shape (F(15,169)=4.2, p=1e-6; CVP=50.2% (CI:41.6%-58.4). On Grande-Terre, the specimens from the different sites do not differ in size (X 2 =5.5, df=6, p=0.5), but differ in shape (F(78,588)=1.4, p=0.02; CVP=28.4% (CI:14.3-50.%)). During the ECA the populations do not differ in either size (W=41, p=0.7) or shape (F(5,11)=1.4, p=0.3), nor do they differ during the LCA (size: X 2 =2.2, df=4, p=0.7; shape: F(36,64)=1.2, p=0.2). However, specimens attributed to the Early and Late Ceramic differ in shape (F(6,103)=4.2, p=0.0008; CVP=67.8% (CI=64.5-71.9%) but not in size (W=1317, p=0.3).

Similarly to the ones from Grande-Terre, Basse-Terre populations differ in shape (F(115,240)=1.4, p=0.02; CVP=22.8% (CI:12.3-33.5%)), but not in size (X 2 =4.9, df=5, p=0.4).

Finally and again similarly, in Marie-Galante, the populations do not differ in size (X 2 =6.2, df=9, p=0.7) but differ in shape (F(66,816)=2.03, p=6.1e-06); CVA=24.6% (CI:16.1-33.9); SI.5.1-2). Specimens attributed to the Early and Late Ceramic differ in shape (F(12,143)=3.31, p=0.0003; CVP=63% (CI:59.5-66.3%), but not in size (W=2646, p=0.2). We detect no differences between the ECA and ECB (size: X 2 =1.1, df=1, p=0.29; shape: F(16,66)=1.1, p=0.4) whereas specimens differ in shape between the LCA and LCB (F(2,70)=5.5, p=0.006; CVP= 65.1% (CI=50-81.3%)), but not size (W=323, p =0.3; SI.5.1-2).

DISCUSSION

Three morphometric clusters, corresponding to three biogeographic units, were identified from the molar size and shape variation: one in Martinique in the south, one in the center islands of the archipelago (Barbuda, Antigua, Guadeloupe, and Marie-Galante), and one in the Northern islands (including Saint-Martin, Saba, Saint-Eustatius, Saint-Kitts, and Nevis).

Morphological distances between island cannot be explained by the geographic distances between them since some geographically close islands are distant morphometrically (e.g. Antigua (central cluster) is 83 km far from Nevis (northern cluster), and 106 km far from Basse-Terre (central cluster)). This geographic variation greatly outweighs temporal variation, with only slight differences in molar morphology linked to cultural time periods within each geographical cluster. Our results thus support long term biogeographic patterning of morphological variation over the span of ca. 2,000 years.

Morphological diversity and rice rat taxonomy

By only working on the first lower molars only a small portion of the entire phenotype of the organism is quantified. However, teeth are the most abundant rodents remains in archeological or paleontological sites, and they are widely used to infer the systematic, taxonomy and spatio-temporal patterns in this group (e.g. Hulme-Beaman et al., 2018a;[START_REF] Stoetzel | Systematics and evolution of the Meriones shawii/grandis complex (Rodentia, Gerbillinae) during the Late Quaternary in northwestern Africa: Exploring the role of environmental and anthropogenic changes[END_REF]. Tooth morphology is the result of both an adaptive and an heritability component [START_REF] Bader | Heritability of dental characters in the house mouse[END_REF][START_REF] Polly | Heritability: the link between development and the microevolution of molar tooth form[END_REF][START_REF] Renaud | Conserved phenotypic variation patterns, evolution along lines of least resistance, and departure due to selection in fossil rodents[END_REF]. Given the absence of genetic and morphometric data on exactly the same specimens, which make it impossible to draw definitive conclusions on the taxonomy of rice rats, the strong biogeographic patterning observed in tooth morphology could nonetheless be used to infer the diversity of Antillean rice rats and discuss taxonomical attributions. Our results reveal three distinct morphotypes likely corresponding to the three genera previously described in earlier morphometric and ancient DNA research [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF][START_REF] Turvey | Taxonomy, phylogeny, and diversity of the extinct Lesser Antillean rice rats (Sigmodontinae: Oryzomyini), with description of a new genus and species[END_REF]. The Martinican archaeological specimens (89 specimens) likely correspond to Megalomys desmarestii [START_REF] Fischer | Synopsis Mammalium[END_REF], the only species described from the island [START_REF] Friant | Notes anatomiques sur les Megalomys des Antilles[END_REF][START_REF] Trouessart | Note sur le rat musqué ("Mus pilorides") des Antilles, type du sousgenre" Megalomys"(Trt) et la place de ce sous-genre dans le groupe des rats américains ou" Hesperomyeae[END_REF] and for which only four specimens have been molecularly analyzed [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF]. Megalomys luciae [START_REF] Major | The musk-rat of Santa Lucia (Antilles)[END_REF] specimens from Sainte-Lucia were not included in this study. However, specimens from Barbuda, where Megalomys audreyae was previously described [START_REF] Hopwood | XLVI.-A fossil rice-rat from the Pleistocene of Barbuda[END_REF], were found to be morphologically closer to specimens from the central islands, including Grande-Terre and Antigua, where Antillomys rayi was genetically identified [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF]. The slight morphometric differences revealed by our analyses (407 specimens) between the central islands may correspond to intra-specific variation within Antillomys rayi although the possibility that our sample includes several distinct species (with morphometrically closely similar first lower molars) could not be excluded. Finally, the third cluster including specimens from the Northern islands (644 specimens) likely corresponds to Pennatomys, with Pennatomys nivalis described from the Saint-Kitts Bank [START_REF] Turvey | Taxonomy, phylogeny, and diversity of the extinct Lesser Antillean rice rats (Sigmodontinae: Oryzomyini), with description of a new genus and species[END_REF]. [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF], based on the Cytochrome b mitochondrial gene, observed some genetic differentiation between islands across the Saint-Kitts Bank, with 2% of genetic divergence between specimens from Nevis and Saint-Kitts, and 5-7% divergence between these specimens and those from Saint-Eustatius. These molecular analyses are in perfect agreement with our morphometrical data (specimens from Nevis and Saint-Kitts being morphological closer than those from Saint-Eustatius) and suggest intraspecific or inter-specific variation. Our results suggest that the two geographically-distant island groupings, Martinique in the South and the Northern islands, are phenotypically more similar to each other, than to those of the geographical closer central islands. This is consistent with molecular data showing a sister relationship between Megalomys and Pennatomys, while Antillomys is more distantly related [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF]. Further research on this insular group taxonomy should seek to combine morphometric analysis with ancient DNA of the same specimens, in order to confirm the taxonomy of all investigated populations.

Influence of ecological factors within clusters

Rice rats from the Northern islands had very small molar size compared to the rest of the archipelago. A similar pattern has been observed in the Anolis lizards from Saint-Martin which particularly small size has been linked to the presence of competition [START_REF] Brown | Character displacement[END_REF][START_REF] Losos | Ecological character displacement and the study of adaptation[END_REF][START_REF] Losos | Adaptation and diversification on islands[END_REF][START_REF] Roughgarden | Anolis lizards of the Caribbean: ecology, evolution, and plate tectonics[END_REF]. Accordingly, the size of the oryzomyines from Saint-Martin and the other northern islands might be caused by the presence of a competitor species (e.g. Amblyrhiza inundata identified in the Anguilla bank during the Pleistocene; [START_REF] Mcfarlane | New specimens of Amblyrhiza inundata (Rodentia: Caviomorpha) from the Middle Pleistocene of Saint Barthélemy, French West Indies[END_REF] or by the existence of peculiar, but yet to be determined, local conditions which impacted species size on these islands.

In the present study comparison between chrono-cultural periods was greatly limited by the number of archaeological sites available for each island and period. Despite these limitations, we detected some differences in shape, but not in size, between diachronic populations, more especially between the Early and Late Ceramic in Martinique, Marie-Galante, and Guadeloupe Grande-Terre. Diachronic differentiation between archaeological rodent populations have been identified, in other species, using a similar methodology (e.g. [START_REF] Cucchi | The changing pace of insular life: 5000 years of microevolution in the Orkney vole (Microtus arvalis orcadensis)[END_REF]Hulme-Beaman et al., 2018b) and has been interpreted as the result of a variety of causes including human landscape modification, climatic change, or a combination of both causes.

In the case of oryzomyine, their past and current distribution ranges on the South American continent indicates that climatic change has affected their distribution [START_REF] Vázquez-Domínguez | Climate Change Impact at the Genetic Level: Patterns in the Couesi's Rice Rat (Oryzomys couesi)[END_REF][START_REF] Vickery | Archaeological Remains of the Rice Rat (Oryzomys) as a Climatic Proxy in the American Midwest[END_REF]. In the Lesser Antilles archipelago, a climatic change is registered around 900-1000 CE, and coincide to the transition between the Early and Late Ceramic Age. This change is linked with a transformation from a wet to a dryer and stormier climate across the archipelago [START_REF] Beets | Climate and pre-Columbian settlement at Anse à la Gourde, Guadeloupe, Northeastern Caribbean[END_REF][START_REF] Bertran | Paléoclimat des Petites Antilles depuis 4000 ans BP : l'enregistrement de la lagune de Grand-Case à Saint-Martin[END_REF]. In between these two periods, Pre-Columbian populations also experienced societal changes, identifiable in material culture and habitat [START_REF] Fitzpatrick | The pre-Columbian Caribbean: Colonization, population dispersal, and island adaptations[END_REF][START_REF] Hofman | Island rhythms: the web of social relationships and interaction networks in the Lesser Antillean archipelago between 400 BC and AD 1492[END_REF][START_REF] Siegel | Paleoenvironmental evidence for first human colonization of the eastern Caribbean[END_REF] and bioarchaeological studies point to a transformation in the management and consumption of resources [START_REF] Grouard | Variation des stratégies de subsistance des Précolombiens à Hope Estate, Saint-Martin (Petites Antilles), d'après l'analyse des restes des petits vertébrés[END_REF][START_REF] Grouard | Modes de vie des Précolombiens des Antilles françaises. Synthèse des données archéozoologiques[END_REF][START_REF] Grouard | Caribbean archaeozoology. Current Advances in Latin-American Archaeozoology[END_REF]Wing, 2001a).

If these elements are to be considered, further investigations are required to define the impact of ecological factors on insular rice rat morphology, which is particularly challenging when dealing with extinct taxa.

No strong evidence for human-mediated dispersal

A proposed northward river-based connection between the Amazon basin and the Caribbean sea during the late Miocene [START_REF] Wilkinson | Megafan environments in northern South America and their impact on Amazon Neogene aquatic ecosystems. Amazonia, Landscape and Species Evolution: A Look into the Past[END_REF] may have facilitated broadly simultaneous overwater dispersal of many South American mainland vertebrates to the Lesser Antilles (review in [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF]. For instance, the genus Leptodactylus (Anura, Leptodactylidae) is considered to have colonized the Lesser Antilles by dispersal across water in the mid-Cenozoic [START_REF] Camargo | Phylogeography of the frog Leptodactylus validus (Amphibia: Anura): patterns and timing of colonization events in the Lesser Antilles[END_REF][START_REF] Hedges | Molecular phylogeny and biogeography of West Indian frogs of the genus Leptodactylus (Anura, Leptodactylidae)[END_REF]. According to genetic data the multiple colonization events of oryzomyine in the archipelago date to the same period (late Miocene) [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF], despite their absence in the paleontological records [START_REF] Grouard | Peuplemens humains et animaux de la Caraïbe depuis 10 000 ans[END_REF]. Our results show only slight phenotypic changes through archaeological chrono-cultural periods, between 500 BCE and 1500 CE, as well as the continuous presence of three clearly defined geographic clusters supporting the hypothesis of an ancient arrival of the group in the archipelago.

Prior to their extinction, the rice rats of the Lesser Antilles lived close to human settlements and crop areas [START_REF] Allen | Extinct and Vanishing mammals of the Western Hemisphere[END_REF][START_REF] Pinchon | Quelques aspects de la nature aux Antilles[END_REF][START_REF] Trouessart | Note sur le rat musqué ("Mus pilorides") des Antilles, type du sousgenre" Megalomys"(Trt) et la place de ce sous-genre dans le groupe des rats américains ou" Hesperomyeae[END_REF]Wing, 2001b). This tendency to commensalism was probably established since the first human occupation in the archipelago. Indeed, zooarchaeological studies highlight their importance in the subsistence economy of local human population throughout the entire Ceramic Age [START_REF] Grouard | Variation des stratégies de subsistance des Précolombiens à Hope Estate, Saint-Martin (Petites Antilles), d'après l'analyse des restes des petits vertébrés[END_REF][START_REF] Grouard | Caribbean archaeozoology. Current Advances in Latin-American Archaeozoology[END_REF]Wing, 2001b) and thus long-term interactions between these rodents and the Pre-Columbian populations. On the other hand, in the north of the archipelago the morphometric variation is well structured per island, a pattern that favor a hypothesis of no (or at least not strong) inflow from external rice rats populations that would have disrupted or smoothed out the inter-island phenotypic structure. In the center, the differences between island phenotypes is less structured, and the possibility of inter-island connections cannot be completely excluded. However, study of additional specimens and archaeological sites would be necessary to confirm these hypotheses. As the prevailing morphometric variation is geographically structured through time we suggest an absence of long-distance connection between islands from the different clusters, and thus an absence of human transport of oryzomyines from one island to another.

Moreover, rice rats fail to meet five of the 10 criteria proposed for classifying species as impacted by humanly-mediated translocations [START_REF] Giovas | The beasts at large-perennial questions and new paradigms for Caribbean translocation research. Part I: Ethnozoogeography of mammals[END_REF][START_REF] Heinsohn | Animal translocation: long-term human influences on the vertebrate zoogeography of Australasia (natural dispersal versus ethnophoresy)[END_REF][START_REF] Heinsohn | Marsupials as introduced species: Long-term anthropogenic expansion of the marsupial frontier and its implications for zoogeographic interpretation. Altered ecologies: Fire, climate and human influence on terrestrial landscapes[END_REF], and two of them could not be applied to this study. Even though the presence of oryzomyines is lacking in the paleontological and archaeological faunal records (criteria 2) prior to the Ceramic Age where they abruptly appear (criteria 3) [START_REF] Grouard | Peuplemens humains et animaux de la Caraïbe depuis 10 000 ans[END_REF], they likely colonized the Lesser Antilles during the late Miocene [START_REF] Brace | Unexpected evolutionary diversity in a recently extinct Caribean mammal radiation[END_REF]. Rice rats show commensal tendency (criterion 5) on the continent [START_REF] Guilday | Archaeological Evidence of Scalopus aquaticus in the Upper Ohio Valley[END_REF][START_REF] Guilday | Animal remains from the Sheep Rock Shelter (36Hu1)[END_REF][START_REF] Vickery | Archaeological Remains of the Rice Rat (Oryzomys) as a Climatic Proxy in the American Midwest[END_REF] and are found in zooarchaeological contexts in association with a plethora of naturally dispersed species (criterion 8) consumed by humans [START_REF] Grouard | Variation des stratégies de subsistance des Précolombiens à Hope Estate, Saint-Martin (Petites Antilles), d'après l'analyse des restes des petits vertébrés[END_REF][START_REF] Grouard | Caribbean archaeozoology. Current Advances in Latin-American Archaeozoology[END_REF][START_REF] Newsom | On land and sea: Native American uses of biological resources in the West Indies[END_REF]Wing, 2001b), as well as with the agouti, another rodent potentially introduced [START_REF] Allen | Extinct and Vanishing mammals of the Western Hemisphere[END_REF][START_REF] Newsom | On land and sea: Native American uses of biological resources in the West Indies[END_REF] and managed [START_REF] Govoni | Paca (Agouti paca) and Agouti (Dasyprocta spp.)-Minilivestock Production in the Amazonas State of Venezuela[END_REF][START_REF] Hardouin | Minilivestock: from gathering to controlled production[END_REF] (criterion 7). At the scale of the archipelago, their distribution is wide (criterion 4), their phenotypic and molecular differentiation is geographically cohesive (criterion 1) and interisland differences persist through time (criterion 6, applied here to morphometric data). Finally, the criteria based on comparisons with historically documented species introduction (criterion 9) and diachronic reconstruction of invasion frontiers (criterion 10) cannot be applied due to data limitation. Overall, the evidence from previous analyses alongside our current research favors a non-anthropic dispersion of the group into the archipelago, or if contacts have existed, newly human-introduced populations from one island to another have not persisted and were not detected.

CONCLUSIONS

This study significantly contributes to our knowledge and understanding of the past diversity of the tribe Oryzomyini in the Lesser Antilles archipelago. Over a thousand specimens of these now extinct taxa were analyzed using geometric morphometrics, allowing the first exploration of their archaeobiogeography. The rice rats show diverse but very homogenous molar morphotypes defined by geographic parameters, which remain largely stable for the 2.000 years of the Ceramic Age in the Lesser Antilles archipelago. The persistence of this strong archaeobiogeographical phenotypic pattern throughout the Ceramic Age supports a scenario of a pre-human dispersal of Oryzomyini species. While rice rats were a component of human diet throughout the Ceramic Age, our overall results do not support an initial hypothesis of humanmediated transport of rice rats between and within the three geographic entities, despite the evidences of transportation of cultivated plants, domesticated animals and raw materials.

Additional studies combining geometric morphometric and ancient DNA analyses on the exact same specimens would allow for the consolidation of the archaeobiogeography, taxonomy and systematics of these extinct endemic rodents, and better identify the environmental adaptations that might have driven the establishment of rice rat populations across the archipelago.

Table legend:

Figures legends:

Figure 1 -Map of the Lesser Antilles archipelago. The seven islands investigated are highlighted and followed by the number of archaeological rice rats (tribe Oryzomyini) teeth analyzed. The number of archaeological sites studied are in brackets. Information about the sites can be found in Table 1. Grey shadows indicate the geological banks exposed during the Pleistocene [START_REF] Hedges | Biogeography of the West Indies: an overview[END_REF][START_REF] Mcphee | Requiem aeternam: the last five hundred years of mammalian species extinctions[END_REF][START_REF] Pregill | Late Quaternary vertebrate Faunas of the Lesser Antilles: Historical components of Caribeean Biogeography[END_REF]. Dashed lines in the North mark the Anegada passage [START_REF] Jany | Geological interpretation of combined Seabeam, Gloria and seismic data from Anegada Passage (Virgin Islands, north Caribbean)[END_REF] and in the South Koopman's Line [START_REF] Genoways | Bats of the Grenadine Islands, West Indies, and placement of Koopman's line[END_REF].

Figure 2 -

 2 Figure 2 -Left: Occlusal view of a first lower molar of a Lesser Antillean rice rat (specimen SRA-Guadeloupe-HE-089-D from Hope Estate, Saint-Martin). Right: Geometric morphometric protocol including one landmark (large yellow dot) and 65 sliding semi-landmarks along the outside curvature of the tooth, recorded in a clockwise direction.

Figure 3 -

 3 Figure 3 -Size variation between rice rat populations of the Lesser Antilles. Boxplots of the log-transformed centroid size of the lower M1. Specimens were grouped by island, site and chronological occupation phase. In light blue: Early Ceramic Age A, dark blue: Early Ceramic Age B, pink: Late Ceramic Age A, red: Late Ceramic Age B. SE: Saint-Eustatius, SK: Saint-Kitts, NEV.: Nevis, ANT.: Antigua, BAR.: Barbuda. The islands names are colored according to the three shape clusters identified (Fig. 4) (purple: Northern islands, yellow: Central islands, green: Southern island).

Figure 4 -

 4 Figure 4 -A. Phenotypic relationship between sites across the Lesser Antilles. Mean branch lengths neighborjoining network of the bootstraped Mahalanobis distances (1000 replicates) with mention of the bootstrap percentages above 50%. Only sites with more than 10 specimens were included. Island names are colored by their geographic and morphometrical cluster attribution (purple: Northern islands, yellow: Central islands, green: Southern islands). B. Map of the studied islands colored by the three shape clusters identified.

Figure 5 -

 5 Figure 5 -Phenotypic relationship between sites of the Northern islands. Mean branch lengths neighborjoining network of the bootstraped Mahalanobis distances (1000 replicates) with mention of the bootstrap percentages above 50%. Site names are colored by chronological occupation phases (light blue: Early Ceramic A, dark blue: Early Ceramic B, pink: Late Ceramic A, red: Late Ceramic B). Only sites with more than 10 specimens were included.

Figure 6 -

 6 Figure 6 -Phenotypic relationship between sites of the Central islands. Mean branch lengths neighbor-joining network of the bootstraped Mahalanobis distances (1000 replicates) with mention of the bootstrap percentages above 50%. Site names are colored by chronological occupation phases (light blue: Early Ceramic A, dark blue: Early Ceramic B, pink: Late Ceramic A, red: Late Ceramic B). M.G.: Marie-Galante, B.T.: Guadeloupe Basse-Terre, GT: Guadeloupe Grande-Terre. Only sites with more than 10 specimens were included.

Table 1 -

 1 Number of archaeological rice rat lower first molars studied, organized by chrono-cultural period, archaeological site and island of origin.

ACKNOWLEDGEMENTS

We would like to acknowledge the Guadeloupe (including Saint-Martin) and Martinique Departments of Archaeology (Regional Office of Cultural Affairs, French Ministry of Culture), Antigua and Barbuda National Parks and the Barbuda Research Complex (BRC), and the Florida Museum of Natural History in Gainesville (FLMNH) who provided the archaeological specimens studied. We acknowledge the morphometric platform of the MNHN, Paris (UMS OMSI). This work was granted by the ATM Blanche program of the MNHN, and the PEPS ECOMOB grant of the CNRS, INEE. We would also like to acknowledge Alex Chepstow-Lusty for language editing, and Carly Ameen, Ashleigh Haruda, Pierre-Henri Fabre, Pierre-Olivier Antoine, and the team of the GAARAnti project for discussion and suggestions. We warmly also thank Andrea Cardini and all the anonymous reviewers who gave helpful comments on earlier versions of the manuscript.

Author contributions:

Author contributions: AE and SG conceived the ideas; DB, KD, SG, SP and GR conducted the fieldwork and collected the material, KD and SG identified the archaeological bones; MD acquired the data; MD and AE performed the analyses; MD, AE, SG, VN, interpreted the results and MD led the writing with assistance from AE, SG and VN.