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Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane Jan 2011

Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

A suite of distinctive freshwater subaerial phosphatic stromatolites is developed close to the northeastern entrance of Deer Cave, Gunung Mulu National Park, Sarawak, Borneo, in conditions of very low light but ample supply of nutrients from guano. These stromatolites are not particulate; they are composed of alternating layers of more porous and more dense amorphous hydroxylapatite. This biomineralization occurs as moulds of coccoid (the majority) and filamentous (less abundant) cyanobacteria. Mineralization occurs at a pH of ~ 7.0 in the extracellular sheaths and in micro-domains of varying carbonate content in the surrounding mucus of the biofilm. The most recent surfaces …


An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias Jan 2010

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation. …


A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg Jan 2010

A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg

WM Keck Science Faculty Papers

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from …


Guano, Donald A. Mcfarlane Jan 2004

Guano, Donald A. Mcfarlane

WM Keck Science Faculty Papers

This is an encyclopedia article.


A New Megalonychid Sloth From The Late Wisconsinan Of The Dominican Republic, Elizabeth Rega, Donald A. Mcfarlane, Joyce Lundberg, Keith Christenson Jan 2002

A New Megalonychid Sloth From The Late Wisconsinan Of The Dominican Republic, Elizabeth Rega, Donald A. Mcfarlane, Joyce Lundberg, Keith Christenson

WM Keck Science Faculty Papers

An unusually well preserved skull, mandible, and indisputably associated post-cranial elements of new sloth, Acratocnus (Miocnus), were recovered from a cave in Jaragua National Park, Dominican Republic. The animal died lying in a rimstone pool and was rapidly coated with a thin calcite patina. We have documented a late Wisconsinan age for this specimen by inorganic 14C radiometric dating of the patina, with supporting data on the carbon systematics of the speleothems in this cave. This sloth is described as a new species on the basis of the distinctive morphology and relative size of cranial and mandibular features. We consider …


A Late Quaternary Paleoecological Record From Caves Of Southern Jamaica, West Indies, Donald A. Mcfarlane, Joyce Lundberg, A.G. Fincham Jan 2002

A Late Quaternary Paleoecological Record From Caves Of Southern Jamaica, West Indies, Donald A. Mcfarlane, Joyce Lundberg, A.G. Fincham

WM Keck Science Faculty Papers

Studies of an unusual and diverse system of caves in coastal southern Jamaica have yielded a paleoclimatic record associated with a fossil vertebrate record that provides useful insights into the poorly documented paleoecology of latest Wisconsinan and Holocene Jamaica. Episodes of significantly increased precipitation during the Holocene have left characteristic deposits of speleothems, and have supported both faunal and archaeological communities that were dependent on these mesic conditions. Deposits of fossil bat guano preserved in the caves provide a δ¹³C record of alternating mesic and xeric climatic episodes that supports the interpretation of the faunal and archaeological record.


Puerto Rican Karst - A Vital Resource, Ariel E. Lugo, Leopoldo Miranda Castro, Abel Vale, Tania Del Mar López, Enrique Hernández Prieto, Andrés García Martinó, Alberto R. Puente Rolón, Adrianne G. Tossas, Donald A. Mcfarlane, Tom Miller, Armando Rodríguez, Joyce Lundberg, John Thomlinson, José Colón, Johannes H. Schellekens, Olga Ramos, Eileen Helmer Aug 2001

Puerto Rican Karst - A Vital Resource, Ariel E. Lugo, Leopoldo Miranda Castro, Abel Vale, Tania Del Mar López, Enrique Hernández Prieto, Andrés García Martinó, Alberto R. Puente Rolón, Adrianne G. Tossas, Donald A. Mcfarlane, Tom Miller, Armando Rodríguez, Joyce Lundberg, John Thomlinson, José Colón, Johannes H. Schellekens, Olga Ramos, Eileen Helmer

WM Keck Science Faculty Papers

The limestone region of Puerto Rico covers about 27.5 percent of the island's surface and is subdivided into the northern, southern, and dispersed limestone areas. All limestone areas have karst features. The karst belt is that part of the northern limestone with the most spectacular surficial karst landforms. It covers 142,544 ha or 65 percent of the northern limestone. The karst belt is the focus of this publication, although reference is made to all limestone regions. The northern limestone contains Puerto Rico's most extensive freshwater aquifer, largest continuous expanse of mature forest, and largest coastal wetland, estuary, and underground cave …


The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford Apr 2000

The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford

WM Keck Science Faculty Papers

The Dream Cave woolly rhinoceros, Coelodonta antiquitatis, is a "classic" specimen of a "cold-stage" fossil fauna from central England. The find was illustrated and described by Dean William Buckland in his seminal tome Reliquiae Diluvianae (1823) during the first half of the 19th century, and made a significant contribution to the development of Buckland's views on the origin of extinct and extirpated fossil vertebrates. The report presents the first, albeit indirect, radiometric dates on the specimen, and argues that the animal fell into the cave just before 37,000 years BP, during the middle of Marine Isotope Stage 3 Interstadial (41 …


New Specimens Of Late Quaternary Extinct Mammals From Caves In Sanchez Ramirez Province, Dominican Republic, Donald A. Mcfarlane, Abel Vale, Keith Christenson, Joyce Lundberg, Gabriel Atilles, Stein Erik Lauritzen Jan 2000

New Specimens Of Late Quaternary Extinct Mammals From Caves In Sanchez Ramirez Province, Dominican Republic, Donald A. Mcfarlane, Abel Vale, Keith Christenson, Joyce Lundberg, Gabriel Atilles, Stein Erik Lauritzen

WM Keck Science Faculty Papers

During the late Quaternary, the island of Hispaniola supported one of the most diverse mammalian faunas in the West Indies. Much of this diversity was lost to extinction in the past 100,000 years, but the timing of these events is poorly known. Here we report the paleontological findings of a multidisciplinary investigation of caves in the central Dominican Republic. These findings include new 'last occurrence' dates for the rodents Isolobodon portoricensis and Brotomys cf. voratus that take these genera to the dawn of the historic era; a first record of a last-interglacial sloth, and the first report of the upper …


Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane Dec 1999

Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has …


A Second Pre-Wisconsinan Locality For The Extinct Jamaican Rodent, Clidomys (Rodentia: Heptaxodontidae), Donald A. Mcfarlane, Joyce Lundberg, Clare Flemming, Ross D. E. Macphee, Stein-Erik Lauritzen Dec 1998

A Second Pre-Wisconsinan Locality For The Extinct Jamaican Rodent, Clidomys (Rodentia: Heptaxodontidae), Donald A. Mcfarlane, Joyce Lundberg, Clare Flemming, Ross D. E. Macphee, Stein-Erik Lauritzen

WM Keck Science Faculty Papers

Clidomys is the most distinctive but least well known member of the late Quaternary terrestrial mammal fauna of Jamaica. Here we report the second dated locality for this genus. The Illinoisan age we report further strengthens arguments we have made elsewhere, that Clidomys represents an early - probably pre-Wisconsinan - extinction that contrasts with the growing record of Holocene extinctions in the Antilles.


The Age Of The Kirkdale Cave Palaeofauna, Donald A. Mcfarlane, Derek C. Ford Apr 1998

The Age Of The Kirkdale Cave Palaeofauna, Donald A. Mcfarlane, Derek C. Ford

WM Keck Science Faculty Papers

The Kirkdale Cave palaeofauna represents the original and classic 'warm', interglacial mammalian cave deposit in Britain. Although long considered to be 'Ipswichian' in age, no previous attempts to obtain radiometric dates have been recorded. Here we report a uranium-series disequilibrium date of 121,000 ± 4000 yr BP on a flowstone capping that overlay the original bone bed. The precision of the date exceeds that obtained at any other British Interglacial cave site, and permits tentative correlation with the high precision ice core records now available.


Jamaican Cave Vertebrates, Donald A. Mcfarlane Jan 1997

Jamaican Cave Vertebrates, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Limestone caves in the tropics are typically associated with a more diverse assemblage of vertebrates than are caves in temperate regions. Chapman [87] for example, has reported 37 species from the caves of Gunung Mulu National Park, Sarawak, whereas Bailey [43] lists only 13 for the equally cavernicolous Guadeloupe Mountains National Park, New Mexico, USA. Twenty-eight vertebrate species have been recorded from Jamaican caves. The relative importance of the five Classes differ in these three areas as shown in Table 1 (overleaf).


Amblyrhiza And The Vertebrate Paleontology Of Anguillean Caves, Donald A. Mcfarlane, Ross D. E. Macphee Jan 1993

Amblyrhiza And The Vertebrate Paleontology Of Anguillean Caves, Donald A. Mcfarlane, Ross D. E. Macphee

WM Keck Science Faculty Papers

Recorded interest in the caves of Anguilla dates back to the second half of the nineteenth century. The earliest explorations were concerned with the locating phosphatic cave earths, and resulted in the mining of several sites. Incidental to this work, the bones of the largest island rodent ever discovered were collected from Aguillan caves. Whereas the phosphate mining operations were short-lived, the remains of the giant rodent Amblyrhiza have catalyzed a continued interest in the caves of Anguilla. The most recent series of explorations have provided the first adequate documentation of Amhlyrhiza fossil sites, and have started to yield radiometric …


Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya Feb 1992

Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Carbon and nitrogen isotope ratios were measured for various ecogeochemical samples relevant to bat guano ecosystems. In particular, ca. 800-year-old subfossil guano from Jackson's Bay Cave Compex, Jamaica, yielded ratios similar to the modern guano from other Jamaican bat caves but quite different from modern guano of the same area. Diagenetic change and differences in bat food habits were unlikely explanations for the observation. Instead, insects that feed on C4 and CAM plants were the main prey for the bats in present Jackson's Bay area, while the ultimate source of organic matter for bats in other Jamaican caves and for …


Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya Feb 1992

Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Nitrogen and carbon isotope ratios were studied in a stratified deposit of guano of Mexican Free-tailed bats in Eagle Creek Cave, Arizona, U.S.A. Little diagenetic change was observed over the 25-year time span of the guano deposit. High aridity and reduced circulation of air in the cave are hypothesized to have slowed the normally rapid decomposition of the excreta and the subsequent escape of resultant ammonia. The results suggest the high dependency of the speed of diagenetic change on specific physical and other conditions of the caves and indicate that great care need be exercised in the interpretation of the …


The Quaternary Bone Caves And Associated Sites At Wallingford, Jamaica, Donald A. Mcfarlane, R. E. Gledhill Jan 1985

The Quaternary Bone Caves And Associated Sites At Wallingford, Jamaica, Donald A. Mcfarlane, R. E. Gledhill

WM Keck Science Faculty Papers

A group of caves associated with the sink of the One Eye River in St. Elizabeth Parish, Jamaica, have been the subject of numerous important palaeontological investigations beginning 1919. Unfortunately, considerable confusion has arisen in the literature through inadequate documentation of different sites. The caves of the immediate area are described and located, and their palaeontological significance is summarised in the light of recent taxonomic review and relevant geochronological evidence.


Liverpool University Expedition To Jamaica, Donald A. Mcfarlane Jan 1980

Liverpool University Expedition To Jamaica, Donald A. Mcfarlane

WM Keck Science Faculty Papers

During summer 1977, five members of the Liverpool University Potholing Club spent six weeks working and exploring in the caves of Jamaica. The team consisted of Don McFarlane, John Dye, Malcolm Macduff, Mike Roger and Barry Williams, all of whom contributed to this report. The expedition base was at Troy, where the villagers are owed a debt of gratitude for their hospitality. This placed the expedition in the heart of the cave region, and a number of new caves and shafts were discovered and explored. The main discovery was the Still Waters Cave, located near Accompong, where 11,800 feet of …