Lehmann, SB and Braun, DR and Dennis, KJ and Patterson, DB and Stynder, DD and Bishop, LC and Forrest, F and Levin, NE (2016) Stable isotopic composition of fossil mammal teeth and environmental change in southwestern South Africa during the Pliocene and Pleistocene. Palaeogeography, Palaeoclimatology, Palaeoecology, 457. pp. 396-408. ISSN 0031-0182
Lehmann et al Palaeo3 accepted.pdf - Accepted Version
Restricted to Repository staff only until 29 April 2018.
Available under License Creative Commons Attribution Non-commercial No Derivatives.
The past 5 million years mark a global change from the warmer, more stable climate of the Pliocene to the initiation of glacial-interglacial cycles during the Pleistocene. Marine core sediment records located off the coast of southwestern Africa indicate aridification and intensified upwelling in the Benguela Current over the Pliocene and Pleistocene. However, few terrestrial records document environmental change in southwestern Africa over this time interval. Here we synthesize new and published carbon and oxygen isotope data of the teeth from large mammals (>6 kg) at Langebaanweg (~5 million years ago, Ma), Elandsfontein (1.0 – 0.6 Ma), and Hoedjiespunt (0.35 – 0.20 Ma), to evaluate environmental change in southwestern Africa between the Pliocene and Pleistocene. The majority of browsing and grazing herbivores from these sites yield enamel 13 C values within the range expected for animals with a pure C3 diet, however some taxa have enamel 13C values that suggest the presence of small amounts C4 grasses at times during the Pleistocene. Considering that significant amounts of C4 grasses require a warm growing season, these results indicate that the winter rainfall zone, characteristic of the region today, could have been in place for the past 5 million years. The average 18O value of the herbivore teeth increases ~4.4‰ between Langebaanweg and Elandsfontein for all taxa except suids. This increase may solely be a function of a change in hydrology between the fluvial system at Langebaanweg and the spring-fed environments at Elandsfontein, or a combination of factors that include depositional context, regional circulation and global climate. However, an increase in regional aridity or global cooling between the early Pliocene and mid-Pleistocene cannot explain the entire increase in enamel 18O values. Spring-fed environments like those at Elandsfontein may have 75 provided critical resources for mammalian fauna in the mid-Pleistocene within an increasingly arid southwestern Africa ecosystem.
|Uncontrolled Keywords:||0403 Geology, 0602 Ecology, 0603 Evolutionary Biology|
|Subjects:||C Auxiliary Sciences of History > CC Archaeology
Q Science > QE Geology
Q Science > QH Natural history > QH301 Biology
|Divisions:||Natural Sciences and Psychology|
|Date Deposited:||28 Apr 2016 08:18|
|Last Modified:||03 Oct 2016 10:44|
|DOI or Identification number:||10.1016/j.palaeo.2016.04.042|
Actions (login required)