Hispaniola is the second-largest island in the West Indies bioregion and along with Cuba is considered the cradle of Greater Antillean rodent evolution and diversification. While the fossil record in ...Hispaniola includes ten extinct species of late Quaternary rodents, only a single species, the Hispaniola hutia (Plagiodontia aedium), is extant on the island. Changes in climate and anthropogenic effects have been suggested as drivers for these extinctions, but there are few radiometric dates associated with these fossils which limits our understanding of the timing of rodent extinctions on Hispaniola relative to shifts in Holocene climate and major events in human settlement and colonization. We report nine new AMS radiocarbon dates for six endemic rodents of Hispaniola that, when coupled with previously reported dates, provide last occurrence records for eight of the ten extinct rodent species there. Results show that Hispaniola rodent extinction occurred in a series of episodes, with more than half (63.6%) surviving into the late Holocene (4200 cal BP to present), postdating the initial arrival of Ceramic Age Indigenous groups, with extinction likely only after European colonization. This pattern in Hispaniola is consistent with what recent studies have found on the timing of extinction of other terrestrial vertebrates in the West Indies. Results from analysis of stable isotopes of fossil bone suggest that the extinction of endemic rodents from Hispaniola largely also postdate habitat changes following the onset of drier conditions in the late Holocene, suggesting that while climate may have shaped the geographic distribution of species, it probably played a minimal direct role in their extinctions on Hispaniola.
•Nearly 70% of extinct native rodents from Hispaniola survived until the Late Holocene.•Body size of native rodents does not correlate with extinction timing.•Defaunation postdated climatic changes in the Pleistocene-Holocene.•Hispaniola was the initial center of Capromyini rodent radiation and evolution.
Sloths were among the most diverse groups of land vertebrates that inhabited the Greater Antilles until their extinction in the middle-late Holocene following the arrival of humans to the islands. ...Although the fossil record of the group is well known from Quaternary deposits in Cuba, Hispaniola, and Puerto Rico, remains from older units are scarce, limiting our understanding of their evolution and biogeographic history. Here we report the oldest known fossil ground sloth from Hispaniola, represented by an unassociated partial tibia and scapula that are recognized as a single taxon from the late Miocene-early Pliocene of the Dominican Republic. The combination of characters observed on the tibia suggests a close relationship with Megalocnus, otherwise only known from the Pleistocene–Holocene of Cuba. These fossils fill a temporal gap between those previously known from the early Miocene of Cuba and those from Pleistocene–Holocene deposits in the region and provide additional support for a continuous presence of the group in the Greater Antilles since the Oligocene.
Abstract
Ancient biomolecule analyses are proving increasingly useful in the study of evolutionary patterns, including extinct organisms. Proteomic sequencing techniques complement genomic ...approaches, having the potential to examine lineages further back in time than achievable using ancient DNA, given the less stringent preservation requirements. In this study, we demonstrate the ability to use collagen sequence analyses via proteomics to assist species delimitation as a foundation for informing evolutionary patterns. We uncover biogeographic information of an enigmatic and recently extinct lineage of Nesophontes across their range on the Caribbean islands. First, evolutionary relationships reconstructed from collagen sequences reaffirm the affinity of Nesophontes and Solenodon as sister taxa within Solenodonota. This relationship helps lay the foundation for testing geographical isolation hypotheses across islands within the Greater Antilles, including movement from Cuba toward Hispaniola. Second, our results are consistent with Cuba having just two species of Nesophontes (N. micrus and N. major) that exhibit intrapopulation morphological variation. Finally, analysis of the recently described species from the Cayman Islands (N. hemicingulus) indicates that it is a closer relative to N. major rather than N. micrus as previously speculated. This proteomic sequencing improves our understanding of the origin, evolution, and distribution of this extinct mammal lineage, particularly with respect to the approximate timing of speciation. Such knowledge is vital for this biodiversity hotspot, where the magnitude of recent extinctions may obscure true estimates of species richness in the past.
Zooarchaeological analysis and isotopic niche space modelling of faunal remains excavated from the settlement of El Carril (ca. AD 1100–1500) in the northern Dominican Republic provides evidence that ...the site was situated along an important transportation corridor for the passage of animal commodities. This study qualitatively investigates faunal remains recovered from sample excavation units within the site and relates these findings to a previously conducted palaeobotanical study of the site. The zooarchaeological findings are compared to that of nearby El Flaco, a smaller settlement located 2.5 km to the east and for which zooarchaeological and palaeobotanical data is available. Isotopic niche space modelling was conducted on animal remains from both sites to relatively indicate different ecological zones that were targeted by Indigenous peoples, and to speculate whether native
Isolobodon portoricensis
hutias (Capromyinae) were arriving to El Carril from different regions. Our evidence of animal resources arriving from far-flung environments, and the isotopic niche space modelling all suggest that El Carril may been situated near an important transportation corridor for animal goods passing between the coastline, the Cordillera Septentrional, and the riverine environments of the Cibao Valley.
We report late Quaternary fossils of the hind limb (tibiotarsus, tarsometatarsus, hallux, pedal phalanges) of an extinct species of eagle (Accipitridae) from Hispaniola (Haiti, Dominican Republic). ...We are unable to refer these 24 fossils with confidence to any Accipitrid genus, living or extinct. Among living genera, the Hispaniolan fossils are most similar in nonquantitative characters to leg elements in Geranoaetus Kaup 1844, as represented in our comparisons by the South American species Black-chested Buzzard-Eagle (G. melanoleucus Vieillot 1819). Although it may be that Geranoaetus eventually will be found to accommodate the Hispaniolan eagle and perhaps other large, extinct species of West Indian eagles (from Cuba and Bahamas), the fossil material available at this time is inadequate. Generic assignment is complicated further by uncertain generic limits among surviving New World buteonine/buteogalline hawks and eagles, which themselves also are not well represented in scientific collections. Measures of the tibiotarsus suggest the Hispaniolan eagle was 15–30% larger than the extant Golden Eagle (Aquila chrysaetos). It is likely that the large Hispaniolan eagle went extinct along with, and potentially as a consequence of, the extinction of most endemic species of large- and medium-sized mammals (primates, rodents, and sloths) that once served as prey.
This study analyses zooarchaeological material recovered from the late precolumbian site of El Flaco (AD 990-1450), northern Dominican Republic. The faunal assemblage from this inland settlement ...demonstrates terrestrially focused modes of faunal exploitation but with some resources obtained from coastal ecosystems, such as mangrove forests, sandy-bottom, and reefs, which are located approximately 20 km to the northwest. This study establishes last occurrence dates for extinct taxa; examines the spatial distribution of fauna; explores modes of food procurement; and the effects of agricultural activities on local fauna by investigating animal remains from three excavation units. A diachronic study of animal remains from one artificial mound demonstrates changing patterns in resource exploitation, such as an increasing consumption of land crab over a roughly 100-year period. This study follows previous research that examined the isotope ecology of endemic species from El Flaco that indicates some hutias were possibly scavenging or being fed cultivated plants. Palaeoenvironmental data suggest that Indigenous landscape transformations led to the creation of mosaic environments, which may have attracted and supported certain species, implying that the inhabitants of El Flaco likely did not have to venture far to trap or hunt many of the animals upon which they relied.
Analysis of largely unstudied fossil collections recovered from caves and sinkholes from western Hispaniola has resulted in the recognition of a new capromyine rodent (
Zagoutomys woodsi
, gen. et ...sp. nov.) and a new solenodontid (
Solenodon ottenwalderi
sp. nov.). Fossils of
Z. woodsi
show that it differs from other capromyine rodents in having a mandible with a relatively thin and elongated symphysis, a relatively long diastema between the lower incisor and dp4, a more procumbent incisor, and a more anteriorly positioned masseteric crest. Results from a phylogenetic analysis suggest that
Z. woodsi
is closely related to the
Plagiodontia
clade, which includes living
P. aedium
and two extinct species. While fossils referred to
Z. woodsi
are rare (
n
= 18) among the thousands of rodent specimens recovered from the study sites, their geographic distribution suggests it was present across western Hispaniola. In contrast, fossils of
S. ottenwalderi
are relatively abundant in several localities but restricted to the western portion of the Tiburon Peninsula, like other regionally endemic extinct taxa, including the platyrrhine primate
Insulacebus toussaintiana
and the capromyine rodent
Rhizoplagiodontia lemkei
. Fossils of
S. ottenwalderi
show that it was notably smaller than other species of Solenodontidae, reducing the body size gap between this genus and
Nesophontes
. A phylogenetic analysis suggests that
S. ottenwalderi
is sister to the extinct species
S. marcanoi
and both are sister to extant
S. paradoxus
, forming a monophyletic clade endemic to Hispaniola. Morphological and body size differences of these two new mammals with respect to their sister taxa might suggest niche differentiation with segregation of available resources in these past island ecosystems.
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