Palaeoenvironmental reconstructions of the interior of South Africa show a wetter environment than today and a non-analogous vegetation structure in the Early Pleistocene. This includes the presence of grasses following both C and C photosynthetic pathways, whereas C grasses decline after the mid-Pleistocene transition (MPT, c. 1.2-0.8 Ma). However, the local terrestrial proxy record cannot distinguish between the potential drivers of these vegetation changes. In this study we show that low glacial CO levels, similar to those at the MPT, lead to the local decline of C grasses under conditions of decreased water availability, using a vegetation model (LPX) driven by Atmosphere-Ocean coupled General Climate Model climate reconstructions. We modelled vegetation for glacial climates under different levels of CO and fire regimes and find evidence that a combination of low CO and changed seasonality is driving the changes in grass cover, whereas fire has little influence on the ratio of C:C grasses. Our results suggest the prevalence of a less vegetated landscape with limited, seasonal water availability, which could potentially explain the much sparser mid-Pleistocene archaeological record in the southern Kalahari.
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http://dx.doi.org/10.1038/s41598-020-72614-2 | DOI Listing |
Nat Commun
January 2025
Irreversible Climate Change Research Center, Yonsei University, Seoul, Republic of Korea.
The recent sea ice changes in the Northern Hemisphere (NH), necessitate elucidating the sea ice variability over the past 2.6 million years (Ma), when the Earth's glacial cycles transitioned from ∼41 to ∼100 kyr periodicity, following the Mid-Pleistocene Transition (MPT) period (0.7-1.
View Article and Find Full Text PDFMol Ecol
February 2025
Department of Biomedical Science and Environmental Biology, College of Life Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan.
Adaptive introgression involves the acquisition of advantageous genetic variants through hybridisation, which are subsequently favoured by natural selection due to their association with beneficial traits. Here, we analysed speciation patterns of the kleptoparasitic spider, Argyrodes lanyuensis, through genomic analyses and tested for possible genetic evidence of adaptive introgression at the Taiwan-Philippines transition zone. Our study used highly polymorphic SNPs to demonstrate that speciation occurred when the Hualien (on Taiwan Island + Green Island) and Orchid Island + Philippine lineages separated during the early to mid-Pleistocene.
View Article and Find Full Text PDFSci Adv
December 2024
Aker BP ASA, Oslo, Norway.
Efforts to understand how Pleistocene climate changes were translated into fluctuations in ice sheet extent and volume are limited by a lack of consensus about the glacial history of the North Sea. Here, we use high-resolution 3D seismic data to interpret the landforms and sediments of the central North Sea in unprecedented detail. In contrast to previous interpretations of multiple extensive early glaciations, our data suggest that grounded ice extended across the central North Sea only once, from western Norway, during the Early Pleistocene.
View Article and Find Full Text PDFNat Commun
November 2024
State Key Laboratory of Tibetan Plateau Earth System and Resources Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
Mol Phylogenet Evol
November 2024
Department of Botany, University of Innsbruck, Sternwartestr. 15, 6020 Innsbruck, Austria. Electronic address:
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