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This paper explores the Holocene climatic dynamics of South Africa's southern Cape, a region that supports a large proportion of the Greater Cape Floristic Region and contains an array of important archaeological sites. While South African climates are generally characterised by marked rainfall seasonality, the southern Cape is currently situated at the interface between tropical and temperate climate systems, resulting in a largely aseasonal rainfall regime. This regime, however, is thought to have been particularly sensitive to past changes in late Quaternary boundary conditions, meaning that variability in either tropical or temperate systems could have significant environmental impacts. Evidence of past climate change, however, remains limited. We present a 9000-year record of hydroclimatic variability obtained from rock hyrax midden stable nitrogen records, from Papkuilsfontein, on the southern slope of the Anysberg Mountains. Resolved to an average 6-year resolution and spanning the period c. 9050 cal yr BP to 1990 CE, this is the highest resolution Holocene record from southern Africa and presents a unique opportunity for the detailed study of the primary drivers and spatial gradients of Holocene climate change in the southern Cape. The data indicate a long-term decrease in aridity across the Holocene and a pattern of variability that reveals remarkable similarities with records from the South African tropics and El Niño–Southern Oscillation proxies, highlighting the significance of tropical systems as drivers of Holocene climate change in the region. This substantially expands what has been previously considered to be the zone of tropical influence, extending from a coastal phenomenon associated with heat transport via the Agulhas Current to encompass much, if not all, of the Agulhas Plain south of the Cape Fold Mountains. These findings provide a valuable new climatic framework for contextualizing changes in ecological and archaeological records in the southern Cape, and contribute to a more comprehensive understanding of the spatio-temporal dynamics of climate systems in southern Africa. • Sub-decadal 9000-year record of aridity from South Africa's southern Cape. • Reveals dominance of tropical forcing across the southern Cape and Agulhas Plain. • ENSO variability indicated to be important driver of regional climate change. • Presents high-resolution framework for study of human-environment interactions. [ABSTRACT FROM AUTHOR]

A fundamental and long-standing question of southern African palaeoclimatology is the way tropical and temperate climate system dynamics have influenced rainfall regimes across the subcontinent since the Last glacial maximum. In this paper, we analyse a selection of recently published palaeoclimate reconstructions along a southwest-northeast transect across South Africa. These records span the last 22,000 years, and encompass the transition between the region's winter and summer rainfall zones. In synthesis, these records confirm broad elements of the dominant paradigm, which proposes an inverse coeval relationship between temperate and tropical systems, with increased precipitation in the winter (summer) rainfall zone during glacial (interglacial) periods. Revealed, however, is a substantially more complex dynamic, with millennial-scale climate change events being strongly – even predominantly – influenced by the interaction and combination of temperate and tropical systems. This synoptic forcing can create same sign anomalies across the South African rainfall zones, contrary to expectations based on the classic model of phase opposition. These findings suggest a new paradigm for the interpretation of southern African palaeoenvironmental records that moves beyond simple binary or additive influences of these systems. [ABSTRACT FROM AUTHOR]

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]

The Palaeo-Agulhas Plain formed an important habitat exploited by Pleistocene hunter-gatherer populations during periods of lower sea level. This productive, grassy habitat would have supported numerous large-bodied ungulates accessible to a population of skilled hunters with the right hunting technology. It also provided a potentially rich location for plant food collection, and along its shores a coastline that moved with the rise and fall of sea levels. The rich archaeological and paleontological records of Pleistocene sites along the modern Cape south coast of South Africa, which would have overlooked the Palaeo-Agulhas Plain during Pleistocene times of lower sea level, provides a paleoarchive of this extinct ecosystem. In this paper, we present a first order illustration of the " palaeoscape modeling " approach advocated by Marean et al. (2015). We use a resourcescape model created from modern studies of habitat productivity without the Palaeo-Agulhas Plain. This is equivalent to predominant Holocene conditions before recent landscape modifications for farming. We then run an agent-based model of the human foraging system to investigate several research questions. Our agent-based approach uses the theoretical framework of optimal foraging theory to model human foraging decisions designed to optimize the net caloric gains within a complex landscape of spatially and temporally variable resources. We find that during the high sea-levels of MIS 5e (+5–6 m asl) and the Holocene, the absence of the Plain left a relatively poor food base supporting a much smaller population relying heavily on edible plant resources from the current Cape flora. Despite high species diversity of plants with edible storage organs, and marine invertebrates, encounter rates with highly profitable resources were low. We demonstrate that without the Palaeo-Agulhas Plain, human populations must have been small and low-density, and exploited plant, mammal, and marine resources with relatively low caloric returns. The exposure and contraction of the Palaeo-Agulhas Plain was likely the single biggest driver of behavioural change during periods of climate change through the Pleistocene and into the transition to the Holocene. • Agent-based model of Later Stone Age human foraging in coastal South Africa. • Reconstructed food resource landscape including mammals, shellfish, and plants. • Sustainable population is under 20 individuals/100 km^2. • Long foraging days (10 + hours per day) and small groups needed to survive. • Edible plants, including USOs, make up 80% or more of the diet. [ABSTRACT FROM AUTHOR]