Repository hosted by TU Delft Library

Home · Contact · About · Disclaimer ·
 

Mid-Holocene vertebrate bone Concentration-Lagerstätte on oceanic island Mauritius provides a window into the ecosystem of the dodo (Raphus cucullatus)

Publication files not online:

Author: Rijsdijk, K.F. · Hume, J.P. · Bunnik, F. · Florens, F.B.V. · Baider, C. · Shapiro, B. · Plicht, J. van der · Janoo, A. · Griffiths, O. · Hoek Ostende, L.W. van den · Cremer, H. · Vernimmen, T. · Louw, P.G.B. de · Bholah, A. · Saumtally, S. · Porch, N. · Haile, J. · Buckley, M. · Collins, M. · Gittenberger, E.
Type:article
Date:2009
Institution: TNO Bouw en Ondergrond
Source:Quaternary Science Reviews, 1-2, 28, 14-24
Identifier: 241345
Keywords: Geosciences · Animals · Bone · Collagen · Drought · Ecology · Mammals · Nucleic acids · Oceanography · Organic acids · Sea level · Water levels · Abiotic conditions · Aridification · Bone collagens · Dry environments · Freshwater lakes · Holocene · Human impacts · Human settlements · Indian Ocean regions · Macrofossils · Mauritius · Micro fossils · Oceanic islands · Plant tissues · Radiocarbon ages · Vertebrate species · Volcanic islands · Ecosystems · anthropogenic effect · aridification · bird · bone · colonization · extinction · fossil record · Holocene · radiocarbon dating · sea level change · Indian Ocean · Indian Ocean islands · Mascarene Islands · Mauritius · Bacillariophyta · Bacteria (microorganisms) · Cylindraspis · Gastropoda · Hexapoda · Raphus cucullatus · Testudinidae · Vertebrata

Abstract

Although the recent history of human colonisation and impact on Mauritius is well documented, virtually no records of the pre-human native ecosystem exist, making it difficult to assess the magnitude of the changes brought about by human settlement. Here, we describe a 4000-year-old fossil bed at Mare aux Songes (MAS) in south-eastern Mauritius that contains both macrofossils (vertebrate fauna, gastropods, insects and flora) and microfossils (diatoms, pollen, spores and phytoliths). With >250 bone fragments/m2 and comprising 50% of all known extinct and extant vertebrate species (ns = 44) of Mauritius, MAS may constitute the first Holocene vertebrate bone Concentration-Lagerstätte identified on an oceanic volcanic island. Fossil remains are dominated by extinct giant tortoises Cylindraspis spp. (63%), passerines (∼10%), small bats (7.8%) and dodo Raphus cucullatus (7.1%). Twelve radiocarbon ages [four of them duplicates] from bones and other material suggest that accumulation of fossils took place within several centuries. An exceptional combination of abiotic conditions led to preservation of bones, bone collagen, plant tissue and microfossils. Although bone collagen is well preserved, DNA from dodo and other Mauritian vertebrates has proved difficult. Our analysis suggests that from ca 4000 years ago (4 ka), rising sea levels created a freshwater lake at MAS, generating an oasis in an otherwise dry environment which attracted a diverse vertebrate fauna. Subsequent aridification in the south-west Indian Ocean region may have increased carcass accumulation during droughts, contributing to the exceptionally high fossil concentration. The abundance of floral and faunal remains in this Lagerstätte offers a unique opportunity to reconstruct a pre-human ecosystem on an oceanic island, providing a key foundation for assessing the vulnerability of island ecosystems to human impact. © 2008 Elsevier Ltd.