Human Arrival and Landscape Dynamics in the Northern Bahamas
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Human arrival and landscape dynamics in the northern Bahamas Patricia L. Falla,1, Peter J. van Hengstumb,c, Lisa Lavold-Footed, Jeffrey P. Donnellye, Nancy A. Alburyf, and Anne E. Tamalavagec aDepartment of Geography and Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223; bDepartment of Marine and Coastal Environmental Science, Texas A&M University, Galveston, TX 77554; cDepartment of Oceanography, Texas A&M University, College Station, TX 77550; dPrivate address, Mesa, AZ 85203; eDepartment of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543; and fNational Museum of The Bahamas, Nassau, The Bahamas Edited by Cathy Whitlock, Montana State University, Bozeman, MT, and approved January 6, 2021 (received for review July 25, 2020) The first Caribbean settlers were Amerindians from South Amer- Few archaeological remains have been recovered from the ica. Great Abaco and Grand Bahama, the final islands colonized in northern Bahamian islands, which include Grand Bahama Island the northernmost Bahamas, were inhabited by the Lucayans when and Abaco Island. On Grand Bahama, Lucayan artifacts were Europeans arrived. The timing of Lucayan arrival in the northern discovered adjacent to a hearth that was dated 1390 to 1500 CE, Bahamas has been uncertain because direct archaeological evi- just prior to Columbus’s arrival (10). On Abaco Island, sinkholes dence is limited. We document Lucayan arrival on Great Abaco preserved the remains of two Lucayan individuals. A human tibia Island through a detailed record of vegetation, fire, and landscape from Sawmill Sink and a human epiphysis recovered from Great dynamics based on proxy data from Blackwood Sinkhole. From Cistern Sinkhole date to 1101 to 1290 CE (2σ range) and 1255 to about 3,000 to 1,000 y ago, forests dominated by hardwoods and 1340 CE (2σ range), respectively (11, 12). Independent of direct palms were resilient to the effects of hurricanes and cooling sea archaeological evidence, the arrival of people in new landscapes σ surface temperatures. The arrival of Lucayans by about 830 CE (2 typically causes profound ecological change, involving fire, defor- range: 720 to 920 CE) is demarcated by increased burning and fol- estation, local extinctions, and invasive plant and animal intro- lowed by landscape disturbance and a time-transgressive shift from ductions. Initial human settlement on islands is often reflected by hardwoods and palms to the modern pine forest. Considering that evidence of burning and vegetation changes preserved in pollen Lucayan settlements in the southern Bahamian archipelago are ENVIRONMENTAL SCIENCES and charcoal records from lakes and wetlands (13–15). However, datedtoabout750CE(2σ range: 600 to 900 CE), these results dem- onstrate that Lucayans spread rapidly through the archipelago in disentangling colonization impacts from synchronous natural en- less than 100 y. Although precontact landscapes would have been vironmental perturbations, such as climate or sea level change, can influenced by storms and climatic trends, the most pronounced be challenging. In The Bahamas, Lucayan arrival has been inferred changes follow more directly from landscape burning and ecosys- previously from increased charcoal deposition and more abundant tem shifts after Lucayan arrival. The pine forests of Abaco declined Pinus caribaea about 1200 to 1250 CE at West Pond, Abaco ’ substantially between 1500 and 1670 CE, a period of increased re- (median age 1175 CE) (16) and at Church s Bluehole, Andros gional hurricane activity, coupled with fires on an already human- (median age 1265 CE) (17). SUSTAINABILITY SCIENCE impacted landscape. Any future intensification of hurricane activity Here, we present a high-resolution record of fire and vegeta- in the tropical North Atlantic Ocean threatens the sustainability of tion history in the northern Bahamas over the last 3,000 y that modern pine forests in the northern Bahamas. Significance anthropogenic burning | Lucayan | Caribbean | pollen | vegetation change The oral history for Amerindian migration through The Baha- he first explorers and settlers in the Caribbean islands were mas was lost after Columbus’s arrival in 1492 CE and Lucayan TAmerindians from South America, who migrated north through enslavement in the early sixteenth century. The Lucayans en- the Lesser Antilles and eventually into the Bahamian archipelago. countered unique prehuman reptile-dominated terrestrial food At European contact, the inhabitants of The Bahamas were the webs (i.e., tortoise and crocodile), with palm and hardwood Lucayans, an Arawakan-speaking Taíno people, whose name forests that were resilient to regional oceanographic cooling translates as “island men” in the native Arawakan language (1). It and hurricane perturbations. New evidence indicates that Lu- cayans arrived in the northern Bahamas by about 830 CE after has been debated whether Lucayans originated from Cuba or – expanding rapidly throughout The Bahamas in less than 100 y. Hispaniola (2 4), but recent analysis of Lucayan skull morphology Following subsequent burning, reptiles were extirpated, and suggests they migrated into the Bahamian archipelago from pyrogenic pine forests took over Great Abaco Island. Com- Hispaniola and Jamaica by 800 CE (5) (Fig. 1). The earliest known pounded perturbations, including forecasts of future hurricane Lucayan settlements in The Bahamas are the Three Dog Site on intensification, may continue to alter Bahamian ecosystems, San Salvador, which was occupied from 600 to 900 CE (2σ range) particularly pine forests, which are less resilient than precon- (6), and the Coralie Site on Grand Turk, occupied 650 to 885 CE tact tropical hardwood ecosystems. (2σ range) (7). Lucayan populations at the time of Columbus’s arrival in 1492 CE on San Salvador (called Guanahani by native Author contributions: P.L.F., P.J.v.H., L.L.-F., J.P.D., N.A.A., and A.E.T. performed research; P.L.F. analyzed data; and P.L.F. and P.J.v.H. wrote the paper with contributions from all. Taíno people) most likely numbered in the tens of thousands (8), The authors declare no competing interest. with lower population densities in the drier southernmost islands This article is a PNAS Direct Submission. (2, 7). Within 30 y, the population of The Bahamas had been This open access article is distributed under Creative Commons Attribution-NonCommercial- greatly reduced by disease and Spanish enslavement to provide NoDerivatives License 4.0 (CC BY-NC-ND). labor on Hispaniola and Cuba (9). Thus, the history of human 1To whom correspondence may be addressed. Email: [email protected]. colonization and ecological impact in The Bahamas depends on This article contains supporting information online at https://www.pnas.org/lookup/suppl/ archaeology and evidence of landscape disturbance because Lu- doi:10.1073/pnas.2015764118/-/DCSupplemental. cayan oral tradition is forever lost. Published March 1, 2021. PNAS 2021 Vol. 118 No. 10 e2015764118 https://doi.org/10.1073/pnas.2015764118 | 1of7 Downloaded by guest on September 26, 2021 85° W 65° W Furthermore, the record illustrates the resilience of Bahamian vegetation to climate variability (e.g., regional sea surface tem- Florida A peratures, hurricanes) prior to human contact, in stark contrast 30° N to the sensitivity of the modern pine-dominated landscape to Blackwood Sinkhole ongoing fires and hurricane activity. ~830 CE Study Site Three Dog Site Church’s Blue Hole ~750 CE The Little Bahama Bank is the northernmost carbonate platform Yucatán in the Bahamian archipelago, with Great Abaco Island and Grand Cuba Coralie Site Bahama Island in the eastern and western margins of the plat- 20° N form, respectively. The local carbonate geology has formed a mature karst landscape with abundant caves and sinkholes. During Jamaica Hispañola Lesser late Pleistocene sea level lowstands, marine carbonate particles were transported by wind into dunes, which created shoreline- Antilles parallel and curvilinear features that characterize the modern topography (SI Appendix,Fig.S1). Modern wetlands often form in the swales between these lithified Pleistocene dunes. 78º W 77º W Blackwood Sinkhole (32 m diameter, about 38 m deep in the Abaco main sinkhole) is positioned about 220 m inland from the coastline Little B Island on a modern topographic high (<10 m above sea level) on the Bahama Bank Blackwood windward margin of northern Great Abaco Island (see Fig. 1; 26.79°N, 77.42°W). The sinkhole is groundwater fed with no 27º N Sinkhole Great inflowing or outflowing streams, and the groundwater level varies Cistern tidally and is co-positioned with sea level (SI Appendix,Fig.S2). Blackwood Sinkhole is surrounded currently by stands of Pinus Grand caribaea var. bahamensis, similar to other northern Bahamian is- Bahama North Providence lands (Great Abaco, Grand Bahama, New Providence, and Channel Andros). Pinus caribaea is limited in the southern Bahamas to Moore’s scattered stands on North and Middle Caicos and Pine Cay (18). Sawmill depth: 12 m Island During heavy rainfall events, low-elevation landscape features Sink within 1 km of Blackwood Sinkhole preferentially flood, including ºN 26 Great a large trough (about 6 km long) lying about 300 m west of the Bahama Bank site. A small wetland about 100 m to the east of the site presently contains salt-tolerant taxa, including Conocarpus erectus (button- C wood or button mangrove) and Typha (cattail). Radiocarbon dating of peat at the underlying limestone contact indicates the emplacement of this wetland by 560 to 595 CE (2σ range) (19). North Atlantic Ocean The Sediment Record and Pollen Preservation Anoxic bottom water has preserved an exceptionally high-quality stratigraphic record in Blackwood Sinkhole (19, 20) (SI Appen- Wetlands dix, Fig. S3). Radiocarbon dating of Blackwood Sinkhole Core 2 (BLWD-C2, collected and sampled in May 2011) indicates the topmost 110 cm of sediment was deposited during the last 3,000 y Blackwood (20). Internal stratigraphic architecture is characterized by lami- nated authigenic carbonate and algal sapropel, with varying Sinkhole quantities of coarse-grained detrital carbonate particles and ter- restrial plant remains.