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Science 16 August 1974:
Vol. 185. no. 4151, pp. 610 - 612
DOI: 10.1126/science.185.4151.610
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Articles

Photosynthetic Mechanisms and Paleoecology from Carbon Isotope Ratios in Ancient Specimens of C4 and CAM Plants

John H. Troughton 1, P. V. Wells 2, and H. A. Mooney 3

1 Department of Plant Biology, Carnegie Institution of Washington, Stanford, California 94305, and Physics and Engineering Laboratory, Department of Scientific and Industrial Research, Private Bag, Lower Hutt, New Zealand
2 Department of Botany, Division of Biological Sciences, University of Kansas, Lawrence 66044
3 Department of Biological Sciences, Stanford University, Stanford, California 94305

Carbon istotope ratios of modern, 10,000-year-old, and more than 40,000-year-old Atriplex confertifolia (C4) material from Nevada caves indicate that the C4 photosynthetic pathway was operating in these plants over that period. Samples of a plant with crassulacean acid metabolism, Opuntia polyacantha, were also measured, and a shift in the 813C value from -21.9 per mil (more than 40,000 years ago) to -13.9 per mil (10,000 years ago) was observed. This provides unique physiological evidence to support the hypothesis that the late Pleistocene pluvial climate in the region already had become drier about 10,000 years ago.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Palaeoenvironments of Early Miocene Kisingiri volcano Proconsul sites: evidence from carbon isotopes, palaeosols and hydromagmatic deposits.
E. A. BESTLAND and E. S. KRULL (1999)
Journal of the Geological Society 156, 965-976
   Abstract »    PDF »
Stable Carbon Isotope Ratios of Rock Varnish Organic Matter: A New Paleoenvironmental Indicator.
R. I. Dorn, R. I. DORN, and M. J. DENIRO (1985)
Science 227, 1472-1474
   Abstract »    PDF »
Plants and the palaeoatmosphere.
P. D. Moore (1983)
Journal of the Geological Society 140, 13-25
   Abstract »    PDF »


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