Isotopic Indications of Late Pleistocene and Holocene Paleoenvironmental Changes at Boodie Cave Archaeological Site, Barrow Island, Western Australia.

Jane Skippington,Peter Veth,Tiina Manne

doi:10.3390/molecules26092582

Abstract

This paper presents the first application of mammal tooth enamel carbonate stable isotope analysis for the purpose of investigating late Pleistocene–early Holocene environmental change in an Australian archaeological context. Stable carbon (δ13C) and oxygen (δ18O) isotope ratios were analyzed from archaeological and modern spectacled hare wallaby (Lagorchestes conspicillatus) and hill kangaroo (Osphranter robustus) tooth enamel carbonates from Boodie Cave on Barrow Island in Western Australia. δ18O results track the dynamic paleoecological history at Boodie Cave including a clear shift towards increasing aridity preceding the onset of the Last Glacial Maximum and a period of increased humidity in the early to mid-Holocene. Enamel δ13C reflects divergent species feeding ecology and may imply a long-term shift toward increasing diversity in vegetation structure. This study contributes new data to the carbonate-isotope record for Australian fauna and demonstrates the significant potential of stable isotope based ecological investigations for tracking paleoenvironment change to inter-strata resolution.

Highlights

Boodie Cave is located on Barrow Island in northwest Australia in an area characterized by dynamic precipitation driven by the influence of winter rainfall and tropical cyclones (Figure 1andFigure 2) [1]
Isotopic measurements were recorded for a total of 69 L. conspicillatus and O. robustus samples
High δ18 O values between 36.6 and 46.2 ka BP demonstrates the local onset of pre-LGM aridity and an early to mid-Holocene low in δ18 O aligns with an increasingly humid period reflected in regional speleothem records, consistent with existing climate models [1,46]

Summary

Introduction

Boodie Cave is located on Barrow Island in northwest Australia in an area characterized by dynamic precipitation driven by the influence of winter rainfall and tropical cyclones (Figure 1andFigure 2) [1]. The archaeological site preserves rich deposits dating from the earliest period of occupation (~50 ky BP) through the post-glacial marine transgression and subsequent islandization (~7 ky BP) [4,5] This provides a unique opportunity to reconstruct past environments and examine the complex relationships between ecological vectors and human populations during the site’s extensive history. The pursuit of further, site-specific paleoenvironmental data is fundamental to expanding understandings of influencing factors including variable precipitation, changing vegetation structure and unstable biological productivity

Methods

Results

Discussion

Conclusion