The stable isotope setting of Australopithecus sediba at Malapa, South Africa.
Date
2016-07
Authors
Holt, E.
Dirks, P.
PLaczek, C.
Berger, L.R.
Journal Title
Journal ISSN
Volume Title
Publisher
Academic of Science of South Africa (ASSAf)
Abstract
We report delta C-13 and delta O-18 results from carbonate-cemented cave sediments at Malapa in South Africa.
The sediments were deposited during a short-period magnetic reversal at 1.977±0.003 Ma, immediately
preceding deposition of Facies D sediments that contain the type fossils of Australopithecus sediba. Values
of delta C-13 range between -5.65 and -2.09 with an average of -4.58±0.54% (Vienna Pee Dee Belemnite,
VPDB) and values of delta O-18 range between -6.14 and -3.84 with an average of -4.93±0.44% (VPDB).
Despite signs of diagenetic alteration from metastable aragonite to calcite, the Malapa isotope values are
similar to those obtained in two previous studies in South Africa for the same relative time period. Broadly,
the Malapa delta C-13 values provide constraints on the palaeovegetation at Malapa. Because of the complex
nature of the carbonate cements and mixed mineralogy in the samples, our estimates of vegetation type
(C4-dominant) must be regarded as preliminary only. However, the indication of a mainly C4 landscape is in
contrast to the reported diet of A. sediba, and suggests a diverse environment involving both grassland and
riparian woodland.
Description
Keywords
palaeovegetation, carbonatecemented, cave sediments, palaeoclimate
Citation
Holt, E. et al. 2016. The stable isotope setting of Australopithecus sediba at Malapa, South Africa. South african Journal of Science 112 (7/8): Article #2015-0351