New South Wales, Australia 140KYr Amino Acid Racemization Data Miller, G.H.; Fogel, M.L.; Magee, J.W.; Gagan, M.K.; Clarke, S.J.; Johnson, B.J. Miller, G.H. Fogel, M.L. Magee, J.W. Gagan, M.K. Clarke, S.J. Johnson, B.J. earth science/paleoclimate/others (M92-A3>LATITUDE -34.085>LONGITUDE 141.903) Most of Australia's largest mammals became extinct 50,000 to 45,000 years ago, shortly after humans colonized the continent. Without exceptional climate change at that time, a human cause is inferred, but a mechanism remains elusive. A 140,000-year record of dietary d13C documents a permanent reduction in food sources available to the Australian emu, beginning about the time of human colonization; a change replicated at three widely separated sites and in the marsupial wombat. We speculate that human firing of landscapes rapidly converted a drought-adapted mosaic of trees, shrubs, and nutritious grasslands to the modern fire-adapted desert scrub. Animals that could adapt survived; those that could not, became extinct. STUDY NOTES: New South Wales, Australia 136KYr Amino Acid Racemization Data LABORTAORY AND ANALYTICAL INFORMATION Samples prepared and analyzed at the University of Colorado, Boulder (CU) Lab PI: Miller, Gifford H. Samples collected and prepared between 1992 and 2003 Pretreatment: Eggshell fragments surface cleaned with dremel tools; 33% leached in 2N HCl in vacuum centrifuge; rinsed with DI water and air dried AA fraction: Total Hydrolysate Hydrolysis procedure: 7N HCl 22 hours 110 deg C Bleach: No Analytical method: IELC Instrumental programming: IELC stepwise buffer change (pH 3.12, 3.86, 10.4) Area or height ratio: height Blank corrections: no Response factors: no Data screening criteria: each sample typically analyzed twice, analyzed again if coefficient of variation >5%. Interlab comparisons: no SAMPLE LOCATION INFORMATION Country or ocean: Australia Region: Darling-Murray State or province or sea: NSW Coordinate precision: ± 5m Datum: WGS84 SAMPLE MATERIAL AND CONTEXT Material type: ratite eggshell Number of individuals: 1 (Lab-ID represents single fragment analysis) Field context: eggshell fragments Field context: lacustrine lunettes Field context: surface collections Collection date: 1992-2002 Collector: Gifford H Miller Sample PI: Gifford H Miller Stratigraphic unit or age: Quaternary Sample ID = "Lab Code + Lab-ID" RESULTS Lab code: AAL Lab number = "Lab Code + Lab-ID" Number of chromatograms: variable; normally > 2 for all IELC analyses Sample or analytical quality AI = A/I NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Miller, G.H. Investigator : Fogel, M.L. Investigator : Magee, J.W. Investigator : Gagan, M.K. Investigator : Clarke, S.J. Investigator : Johnson, B.J. 2011-04-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/10751 https://www1.ncdc.noaa.gov/pub/data/paleo/aar/miller2005nsw/miller2005nsw.xls https://www1.ncdc.noaa.gov/pub/data/paleo/aar/miller2005nsw/miller2005nsw.txt https://www1.ncdc.noaa.gov/pub/data/paleo/aar/miller2005nsw/miller2005nsw.xls https://www1.ncdc.noaa.gov/pub/data/paleo/aar/miller2005nsw/miller2005nsw.txt English https://www.ncdc.noaa.gov/paleo/study/10751 https://www1.ncdc.noaa.gov/pub/data/paleo/aar/miller2005nsw/miller2005nsw.xls https://www1.ncdc.noaa.gov/pub/data/paleo/aar/miller2005nsw/miller2005nsw.txt Miller, G.H., M.L. Fogel, J.W. Magee, M.K. Gagan, S.J. Clarke, and B.J. Johnson. 2005. Ecosystem Collapse in Pleistocene Australia and a Human Role in Megafaunal Extinction. Science, Vol. 309, pp 287-290, 8 July 2005. DOI: 10.1126/science.1111288 START YEAR: 140000 cal yr BP * END YEAR: 0 cal yr BP 141.903 -34.085 141.903 -34.085