scholarly journals The paleoecology and extinction of endemic tortoises in the Bahamian Archipelago

The Holocene ◽  
2019 ◽  
Vol 30 (3) ◽  
pp. 420-427
Author(s):  
David W Steadman ◽  
Nancy A Albury ◽  
Lizabeth A Carlson ◽  
Richard Franz ◽  
Michelle J LeFebvre ◽  
...  
Keyword(s):  
Native Species ◽  
Late Holocene ◽  
Human Settlement ◽  
The Bahamas ◽  
Turks And Caicos Islands ◽  
Human Contact ◽  
Accelerator Mass Spectrometer ◽  
Island Group ◽  
Bahamian Archipelago ◽  
Archeological Site

No native species of tortoises ( Chelonoidis spp.) live today in the Bahamian (Lucayan) Archipelago (= The Bahamas + The Turks and Caicos Islands), although a number of species inhabited these islands at the first human contact in the late-Holocene. Until their extinction, tortoises were the largest terrestrial herbivores in the island group. We report 16 accelerator mass spectrometer (AMS) radiocarbon (14C) dates determined directly on individual bones of indigenous, extinct tortoises from the six Bahamian islands (Abaco, Eleuthera, Flamingo Cay, Crooked, Middle Caicos, Grand Turk) on five different carbonate banks. These 16 specimens probably represent six or seven species of tortoises, although only one ( Chelonoidis alburyorum on Abaco) has been described thus far. Tortoises seem to have survived on most Bahamian islands for only one or two centuries after initial human settlement, which took place no earlier than AD ~700–1000. The exception is Grand Turk, where we have evidence from the Coralie archeological site that tortoises survived for approximately three centuries after human arrival, based on stratigraphically associated 14C dates from both tortoise bones and wood charcoal. The stable isotope values of carbon (σ13C) and nitrogen (σ15N) of dated tortoise fossils show a NW-to-SE trend in the archipelago that may reflect increasing aridity and more consumption of cactus.

scholarly journals Absence of Saharan dust influence on the strontium isotope ratios on modern trees from the Bahamas and Turks and Caicos Islands

2018 ◽  
Vol 89 (2) ◽  
pp. 394-412 ◽  
Author(s):  
Rick Schulting ◽  
Mike Richards ◽  
John Pouncett ◽  
Bryan Naqqi Manco ◽  
Ethan Freid ◽  
...  
Keyword(s):  
Late Quaternary ◽  
Saharan Dust ◽  
Soil Types ◽  
Sr Isotope ◽  
The Bahamas ◽  
Turks And Caicos Islands ◽  
Order Of Magnitude ◽  
The Caribbean ◽  
The Impact ◽  
Bahamian Archipelago

AbstractWe report on strontium (87Sr/86Sr) isotope results from 91 modern trees growing on the Bahamas and Turks and Caicos Islands. The average87Sr/86Sr ratio of 0.709169±0.000010 is consistent with the late Quaternary limestone of the islands and with the modern ocean value. The absence of any detectable influence of87Sr-enriched Saharan dust is notable, given the known contribution of this material to both past and recent soils of the Caribbean. Our results indicate that the impact of Saharan dust to the modern biosphere of the Bahamian archipelago is at least an order of magnitude less than modeled in currently available strontium isoscapes for the circum-Caribbean. We suggest that the bioavailability of Sr in Saharan dust may be considerably less than previously thought. Nevertheless, further work could usefully be carried out in the Bahamian archipelago on plants with different rooting depths, growing on different soil types and on limestone of different ages. Our results have particular relevance for the refinement of existing strontium isoscapes and the archaeological provenience of artifacts, animals, and people in the circum-Caribbean.

Holocene vertebrates from a dry cave on Eleuthera Island, Commonwealth of The Bahamas

The Holocene ◽  
2017 ◽  
Vol 28 (5) ◽  
pp. 806-813 ◽  
Author(s):  
David W Steadman ◽  
Nancy A Albury ◽  
Jim I Mead ◽  
J Angel Soto-Centeno ◽  
Janet Franklin
Keyword(s):  
Late Holocene ◽  
Terrestrial Plants ◽  
Human Occupation ◽  
The Bahamas ◽  
Sea Levels ◽  
Southeastern Myotis ◽  
Accelerator Mass Spectrometer ◽  
Myotis Myotis ◽  
Vertebrate Assemblage ◽  
Myotis Austroriparius

We report a mid- to late-Holocene, non-cultural vertebrate assemblage from Garden Cave (site EL-229), Eleuthera Island, The Bahamas, with 2450 fossils representing 26 species. The chronology is based on accelerator mass spectrometer (AMS) radiocarbon (14C) dates determined directly on individual bones of the hutia ( Geocapromys ingrahami), an extirpated species of rodent that dominates the bone assemblage at Garden Cave. Four AMS 14C dates from our excavation range from 1340 to 1280 cal. BP (surface of the site) to 4860 to 4830 cal. BP with depth. A hutia bone lying on the surface from elsewhere in the cave dated to 450 to 290 cal. BP, which is roughly the time of European and African contact on Eleuthera. Other extirpated species from Garden Cave are tortoise ( Chelonoidis sp.), rock iguana ( Cyclura sp.), skink ( Mabuya sp.), parrot ( Amazona leucocephala), crow ( Corvus nasicus), and southeastern myotis ( Myotis austroriparius). Each of these species may have survived on Eleuthera until sometime after the initial human occupation of the island (~1000 cal. BP), although we have direct AMS 14C dates for only the hutia. During the time of fossil deposition in Garden Cave, sea levels were approaching that of today, yet land areas were considerably larger than now, connecting Eleuthera to New Providence, and potentially to Exuma as well. Such relatively recent connections are important in explaining past and present distributions of terrestrial plants and animals.

Human occupation strategies and related environmental-climate during the middle and late Holocene in central Pampas of Argentina

The Holocene ◽  
2018 ◽  
Vol 29 (2) ◽  
pp. 244-261 ◽  
Author(s):  
Pablo G Messineo ◽  
Marcela S Tonello ◽  
Silvina Stutz ◽  
Alfonsina Tripaldi ◽  
Nahuel Scheifler ◽  
...  
Keyword(s):  
Late Holocene ◽  
Specific Activity ◽  
Climatic Conditions ◽  
Hard Material ◽  
Human Occupation ◽  
Climate Conditions ◽  
Lithic Assemblage ◽  
Depositional Rate ◽  
Archeological Site ◽  
Middle And Late Holocene

The main objective of this work is to generate and integrate interpretations of human occupation strategies and inferences of the environmental-climatic conditions in the central Pampas during the middle and late Holocene. We present a novel archeological–geological–paleoecological analysis in the area of the Cabeza de Buey lake, placed in an aeolian landscape. During the middle Holocene, two events of human occupations were recognized at Laguna Cabeza de Buey 2 archeological site. Both events present a small amount of lithic materials, a low diversity of tools and activities developed with them (principally hard material), and the hunting and primary processing of artiodactyls. These evidences suggest a locus of specific activity associated with an ephemeral human settlement under climate conditions drier than present and the presence of small, brackish, and shallow water bodies. For the late late Holocene, the hunter-gatherer occupation has a higher depositional rate of lithic assemblage, stones with diverse origins, presence of pottery fragments, a great lithic tool diversity, knapping techniques, and activities developed with these tools (processing wood, bone, hide, non-woody plant, and soft material). These evidences reveal an occupation with a higher degree of recurrence represented by a locus of multiple activities associated with a more stable landscape, such as an environment of dunes fixed by grass vegetation, and the establishment of a permanent water body. The different environmental characteristics for the middle and late Holocene in this area promoted that human groups develop two different patterns of mobility, settlement and use of space.

Late Holocene Historical Ecology: The Timing of Vertebrate Extirpation on Crooked Island, Commonwealth of The Bahamas

2017 ◽  
Vol 12 (4) ◽  
pp. 572-584 ◽  
Author(s):  
David W. Steadman ◽  
Hayley M. Singleton ◽  
Kelly M. Delancy ◽  
Nancy A. Albury ◽  
J. Angel Soto-Centeno ◽  
...  
Keyword(s):  
Late Holocene ◽  
Historical Ecology ◽  
The Bahamas

scholarly journals Absence of Saharan dust influence on the strontium isotope ratios on modern trees from the Bahamas and Turks and Caicos Islands – ERRATUM

2018 ◽  
Vol 90 (1) ◽  
pp. 251-251 ◽  
Author(s):  
Rick Schulting ◽  
Mike Richards ◽  
John Pouncett ◽  
Bryan Naqqi Manco ◽  
Ethan Freid ◽  
...  
Keyword(s):  
Isotope Ratios ◽  
Strontium Isotope ◽  
Saharan Dust ◽  
The Bahamas ◽  
Turks And Caicos Islands ◽  
Strontium Isotope Ratios

Chronology and causes of the extinction of the Lava Mouse,Malpaisomys insularis(Rodentia: Muridae) from the Canary Islands

2008 ◽  
Vol 70 (2) ◽  
pp. 141-148 ◽  
Author(s):  
Juan Carlos Rando ◽  
Josep Antoni Alcover ◽  
Juan Francisco Navarro ◽  
Francisco García-Talavera ◽  
Rainer Hutterer ◽  
...  
Keyword(s):  
Invasive Species ◽  
Atlantic Ocean ◽  
Alien Species ◽  
Canary Islands ◽  
Mus Musculus ◽  
Late Holocene ◽  
Human Impacts ◽  
Eastern Atlantic Ocean ◽  
Accelerator Mass Spectrometer ◽  
Owl Pellets

AbstractUnderstanding late Holocene extinctions on islands requires accurate chronologies for all relevant events, including multiple colonisations by humans and the introduction of alien species. The most widely held hypothesis on the causes of Holocene island vertebrate extinctions incorporates human impacts, although climatic-related hypotheses cannot be excluded. Both hypotheses have been suggested to account for the extinction of the endemic Lava Mouse,Malpaisomys insularisfrom the Canary Islands. Here we present the first accelerator mass spectrometer (AMS)14C ages from collagen ofM. insularisbones from ancient owl pellets collected at Fuerteventura (Canary Islands, eastern Atlantic Ocean). These new dates contribute to an understanding of the extinction of this species. We are able to exclude climatic causes, predation by invasive species, and competition with the house mouse,Mus musculus. The arrival of Europeans in the Canary Islands correlates with the extinction ofMalpaisomys. The introduction of rats,Rattusspp., together with their parasites and diseases, emerges as the most reasonable hypothesis explaining the extinction ofM. insularis.

scholarly journals Vertebrate community on an ice-age Caribbean island

2015 ◽  
Vol 112 (44) ◽  
pp. E5963-E5971 ◽  
Author(s):  
David W. Steadman ◽  
Nancy A. Albury ◽  
Brian Kakuk ◽  
Jim I. Mead ◽  
J. Angel Soto-Centeno ◽  
...  
Keyword(s):  
Sea Level ◽  
Late Pleistocene ◽  
Late Holocene ◽  
Ice Age ◽  
Caribbean Island ◽  
The Bahamas ◽  
Broadleaf Forest ◽  
The Past ◽  
Scuba Divers ◽  
Moist Habitat

We report 95 vertebrate taxa (13 fishes, 11 reptiles, 63 birds, 8 mammals) from late Pleistocene bone deposits in Sawmill Sink, Abaco, The Bahamas. The >5,000 fossils were recovered by scuba divers on ledges at depths of 27–35 m below sea level. Of the 95 species, 39 (41%) no longer occur on Abaco (4 reptiles, 31 birds, 4 mammals). We estimate that 17 of the 39 losses (all of them birds) are linked to changes during the Pleistocene–Holocene Transition (PHT) (∼15–9 ka) in climate (becoming more warm and moist), habitat (expansion of broadleaf forest at the expense of pine woodland), sea level (rising from −80 m to nearly modern levels), and island area (receding from ∼17,000 km2 to 1,214 km2). The remaining 22 losses likely are related to the presence of humans on Abaco for the past 1,000 y. Thus, the late Holocene arrival of people probably depleted more populations than the dramatic physical and biological changes associated with the PHT.

Sign in / Sign up

Export Citation Format

Share Document