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South Africa's southwestern Cape occupies a critical transition zone between Southern Hemisphere temperate (winter) and tropical (summer) moisture-bearing systems. In the recent geological past, it has been proposed that the relative influence of these systems may have changed substantially, but little reliable evidence regarding regional hydroclimates and rainfall seasonality exists to refine or substantiate the understanding of long-term dynamics. In this paper we present a mid-to late Holocene multi-proxy record of environmental change from a rock hyrax midden from Katbakkies Pass, located along the modern boundary between the winter and summer rainfall zones. Derived from stable carbon and nitrogen isotopes, fossil pollen and microcharcoal, these data provide a high resolution record of changes in humidity, and insight into changes in rainfall seasonality. Whereas previous work concluded that the site had generally experienced only subtle environmental change during the Holocene, our records indicate that significant, abrupt changes have occurred in the region over the last 7000 years. Contrary to expectations based on the site's location, these data indicate that the primary determinant of changes in humidity is summer rather than winter rainfall variability, and its influence on drought season intensity and/or length. These findings are consistent with independent records of upwelling along the southern and western coasts, which indicate that periods of increased humidity are related to increased tropical easterly flow. This substantially refines our understanding of the nature of temperate and tropical circulation system dynamics in SW Africa, and how changes in their relative dominance have impacted regional environments during the Holocene. [ABSTRACT FROM AUTHOR]

Abstract: South Africa's southern coastal margin is recognised as being a highly dynamic climatic region that plays a critical role in both regional and global atmospheric and oceanic circulation dynamics. Our understanding of the past dynamics of this system, however, has been limited by the number and nature of datasets available that can be used to infer changes in key climatic parameters in the region. In this paper we present new high resolution δ13C and δ15N data from two independently dated rock hyrax (Procavia capensis) middens from Seweweekspoort in South Africa's Groot Swartberg mountains. These data provide information regarding both past vegetation and hydroclimatic change, and allow a regional integration of available data that explore the long-term dynamics of mid-latitude circulation systems in the African sector of the Southern Hemisphere. Combined, a negative relationship is apparent between temperature and humidity in this area of the southern Cape, and these changes can for the first time be clearly linked to variations in Antarctic sea-ice extent and shifts in the southern westerly storm track. This dynamic is particularly evident between 5 and 7 cal kBP, when a reduction in sea-ice extent and a southward shift of the westerlies are manifested regionally by increased temperatures and a phase of marked aridity. [Copyright &y& Elsevier]

This paper reviews past and present distributions of murid (mice and rats) and soricid (shrew) species from the Pinnacle Point fossil sites PP5-6N, PP9C, PP13B, and PP30, as well as the coastal site of Knysna Eastern Heads Cave 1. The positioning of these sites on the edge of the Palaeo-Agulhas Plain resulted in the micromammal communities being exposed to rapid landmass changes through sea-level regressions and transgressions, as well as climatic and environmental fluctuations during glacial-interglacial cycling. Together, Pinnacle Point and Knysna preserve a composite coastal sequence from MIS 9 to MIS 1, and provide an opportunity to assess the long term sensitivity of micromammals to environmental change. Modern distributional information for the south coast region was obtained from owl pellet and small-carnivore scat assemblages, and extended the known current distributions of six murids. A uniform suite of micromammals was pervasive throughout all the fossil sites, during both glacial and inter-glacial cycling, and the composition of the majority of fossil micromammal assemblages remained unchanged, despite fluctuations in rainfall amount, seasonality, and the proportion of C3 versus C4 vegetation. This suggests an ability to adapt to, and cope with, climatic and environmental changes with relative ease. The fact that the fossil evidence indicates that many murid taxa occupied different ranges in the past, and, in some cases, had considerably more extensive ranges, and lived in a greater variety of habitats, raises a note of caution regarding using current biogeographies to elucidate palaeoenvironmental and climatic change, and for biogeographic and species distribution modelling. • The Palaeo-Agulhas Plain was populated by a unique flora and micromammalian fauna. • The micromammal population remained relatively unaffected by glacial-interglacial cycling. • Climate change cannot always be assumed to affect small mammal distributions. • The current biogeography of many micromammals differs to that of the past. • Current understanding of small mammal distributions is extremely poor and inaccurate. [ABSTRACT FROM AUTHOR]