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The giant Cape zebra (Equus capensis) is one of the extinct Quaternary large mammal species of southern Africa, and the largest equid from the Quaternary of Africa. Twenty-six Pleistocene equid tracksites have been identified in aeolianites on the Cape south coast of South Africa. An age range of 161 ± 12 ka to 43 ± 4 ka has been established through Optically Stimulated Luminescence. More than half of the sites contain large-equid tracks, representing the first ichnosites attributed to E. capensis. Smaller equid tracks may have been registered by the quagga (E. quagga quagga). The abundance of E. capensis tracksites on the Cape south coast contrasts with the paucity of body fossils of the species from the region, contrasting with the impression obtained from the body fossil record that E. capensis was predominantly a west coast species in the region. The new data illustrate the capacity of the body fossil and trace fossil records to complement each other. The loss of suitable habitat provided by the Palaeo-Agulhas Plain was probably a contributing factor in the extinction of this large-bodied grazer. A long trackway at Driefontein, attributed to E. capensis, adds to a sparse global record of fossil horse trackways.

Although tortoises (Testudinidae) are a familiar clade of reptiles, with a body fossil record extending to at least the Eocene, hitherto no tortoise ichnosites have been described. Here, a number of sites attributed to tortoise trackmakers are identified within Pleistocene aeolianites on South Africa's Cape south coast. These date from late Marine Isotope Stage 6 to Marine Isotope Stage 4. The findings indicate large trackmakers, with evidence of a trackmaker length of more than a meter—substantially longer than the largest extant tortoises in southern Africa. This suggests either the presence of an extinct very large tortoise species, or that Pleistocene leopard tortoises in the region were larger than their descendants. Variations in substrate properties are responsible for a variety of track and trace forms. A mismatch exists between the reported ichnological evidence for large tortoises, and the regional archaeological and body fossil records, which almost exclusively comprise smaller tortoises. The findings illustrate the potential of ichnology to complement and augment the paleontological and archaeological records.

A multi-proxy study on a sediment core from Pedro Palo Lake, a mid-altitude endorheic Andean Lake in northern South America, was carried out to understand the effects of human activities and climate variability on tropical mountain freshwater ecosystems. Results indicate that between ~ 7980 and 4110 cal year BP the lake maintained well-mixed, mesotrophic conditions, within which a diverse planktonic and benthic diatom community flourished. From 4110 to about 2050 cal year BP, benthic diatoms almost disappeared, and the planktonic community changed to include small Discostella spp. and large Fragilaria species, suggesting higher nutrient concentrations and possibly, more turbid waters. At this time, peaks in charcoal concentration and in the sedimentary C/N ratio imply that forest fires in the watershed intensified and that more organic matter, derived from terrestrial vegetation, accumulated in the lake. This period coincides with an increase in population, and in the social, technological and agricultural complexity of indigenous peoples. We propose that anthropogenic activities, burning and deforestation, increased the nutrient load to the lake causing the observed changes in the diatom communities. After 2050 cal year BP, periphytic diatoms returned, the intensity and frequency of fires diminished, and a secondary forest grew. We infer an associated decrease in nutrients, resulting from reforestation and/or lower water levels caused by drier climates. Estimations based on the age model of the core suggest that it took approximately 30 years for the lake to change from its most degraded state in the middle Holocene to its state in the late Holocene. However, the much-reduced diversity of the diatom community after ~ 2050 cal year BP indicates that the lake did not rebound to its previous middle Holocene conditions. The record from Pedro Palo is therefore a good example of the detrimental and long-lasting effects of anthropic deforestation.

Topography fundamentally influences the distribution and morphology of aeolian landforms via the modification of surface wind flow and the creation of space for sediment deposition. This has been observed at both landform (individual topographic dune forms) and macro-landscape (sand sea) scales. Although previous studies have considered several aspects of the impact of topography on aeolian landforms, the patterns of landscape-scale aeolian sediment accumulation that emerge at the meso-scale, within topographically complex environments have received less consideration. To address this, we present an approach that combines information on the presence of surficial sand (via remote sensing) with the morphometric feature classification method, LandSerf. Using the Cady Mountains in the Mojave Desert as a case study, we explore the relationships between sand cover and topographic indices over length scales of 102–103 m. Field observations are then used to refine our understanding of these patterns. Aeolian deposits across the Cady Mountains are strongly controlled by the topography. Although sand cover is often continuous and highly variable in depth, four archetypal “accommodation space types” are identified from the morphometric analysis: Slopes, Plains, Valley-Fills, and Slope-Valley composite. Specific aeolian landforms within these accommodation spaces may manifest as sand ramps and climbing - falling dunes, particularly on mountain front Slopes, and as sand sheets on downwind Plains within the mountain block. In areas of high sediment supply these may also coalescence, as exemplified by the extensive and compositionally complex Slope-Valley composites in the northern Cady Mountains. In conjunction with field observations, we argue that topography, moderated by proximity to sediment supply, strongly influences the character of the aeolian sedimentary record. However, even within the relatively complex landscape studied here, 90% of the mapped sand accumulation is associated with the four identified accommodation space types. The implication is that areas of such complex topography are amenable to analysis within the scheme outlined and that this can potentially be used to support interpretations of accompanying dune chronologies.

The southwestern Cape of South Africa is a particularly dynamic region in terms of long-term climate change. We analysed fossil pollen from a 25,000 year sediment core taken from a near-coastal wetland at Pearly Beach that revealed that distinct changes in vegetation composition occurred along the southwestern Cape coast. From these changes, considerable variability in temperature and moisture availability are inferred. Consistent with indications from elsewhere in southwestern Africa, variability in Atlantic Meridional Overturning Circulation (AMOC) was identified as a strong determinant of regional climate change. At Pearly Beach, this resulted in phases of relatively drier conditions (~24–22.5 cal ka BP and ~22–18 cal ka BP) demarcated by brief phases of increased humidity from ~24.5–24 cal ka BP and 22.5–22 cal ka BP. During glacial Termination I (~19–11.7 ka), a marked increase in coastal thicket pollen from ~18.5 to 15.0 cal ka BP indicates a substantial increase in moisture availability, coincident, and likely associated with, a slowing AMOC and a buildup of heat in the southern Atlantic. With clear links to glacial and deglacial Earth system dynamics and perturbations, the Pearly Beach record represents an important new contribution to a growing body of data, providing insights into the patterns and mechanisms of southwestern African climate change.

To address long-standing questions concerning Southern Hemisphere climate dynamics and palaeoecological change in southern Africa, a Late Glacial-Holocene alluvial sediment sequence from the relatively dry interior year-round rainfall zone in South Africa was investigated. The study site borders the Fynbos biome and Succulent Karoo biome ecotone, and comprises a rare stratified sequence of sandy and organic-rich silt deposits, shown to span the last 14,000 years. A high resolution multi-proxy record of ecological change was derived using pollen, phytoliths and organic geochemical analyses. For the period 14–11 ka, significant valley aggradation occurred under relatively drier conditions, followed, during the early and middle Holocene, by alternating phases of humid and dry events with higher stream energy, slower accumulation or subtle seasonality changes. A transition from relatively humid to more arid conditions at 4–3 ka is identified and is consistent in timing with several interior year-round rainfall zone records. Results revealed alternations of fynbos and karroid elements and C3/C4 grasses throughout the last fourteen thousand years, but did not suggest large-scale biome shifts. The record joins a growing number of sites contributing to debate over the complex atmospheric-oceanic drivers of palaeoclimate in this region. These data broadly fit to the regional pattern for the southernmost interior of South Africa in showing alternating influences from the westerly winter rain systems in the early Holocene, with a greater contribution from subtropical summer rain system during the middle and later Holocene.

The lowland savannas (Llanos) of Colombia and Venezuela are covered by extensive aeolian landforms for which little chronological information exists. We present the first optically stimulated luminescence (OSL) age constraints for dunes in the Llanos Orientales of lowland Colombia and new ages for dunes in the Venezuelan Llanos. The sampled dunes are fully vegetated and show evidence of post-depositional erosion. Ages range from 4.5 ± 0.4 to 66 ± 4 ka, with the majority dating to 27–10 ka (Marine Isotope Stage 2). Some dunes accumulated quickly during the last glacial maximum, although most were active 16–10 ka. Accretion largely ceased after 10 ka. All dunes are elongated downwind from rivers, parallel with dry season winds, and are interpreted as source-bordering features. As they are presently isolated from fluvial sediments by gallery forest it is proposed that activity was associated with a more prolonged dry season, which restricted gallery forest, leading to greater sediment availability on river shorelines. Such variability in dry season duration was potentially mediated by the mean latitude of the ITCZ. The cessation of most dune accretion after ca. 10 ka suggests reduced seasonality and a more northerly ITCZ position, consistent with evidence from the Cariaco Basin.

International audience; South Africa's southern Cape is a highly dynamic climatic region that is influenced by changes in both temperate and tropical atmospheric and oceanic circulation dynamics. Recent research initiatives suggest that the major elements of the regional climate system have acted both independently and in combination to establish a mosaic of distinct climate regions and potentially steep climate response gradients across the southern Cape. To consider this further, we present new high resolution δ 13 C and δ 15 N data from a rock hyrax (Procavia capensis) midden from Baviaanskloof, in the Cape Fold Mountains of South Africa's Eastern Cape Province. Spanning the last 7200 years, these data provide detailed information regarding environmental changes in the mid-and late Holocene, allowing us to assess the spatio-temporal nature of climate change anomalies across the wider region. Throughout the full duration of the record, a negative correlation between humidity and palaeotemperature reconstructions from nearby Cango Cave is observed. In conjunction with correlations with Southern Ocean sea-surface temperatures and sea-ice presence, we infer a dominant influence of the southern westerlies in determining multi-millennial scale hydroclimate variability. At shorter, multi-centennial to millennial timescales, the Baviaanskloof data indicate a clearer expression of tropical influences, highlighting a delicate balance between the mechanisms driving regional climate dynamics across timescales, and the sensitivity of the region to changes in global boundary conditions.

International audience; We present an 8000-year biomarker and stable carbon isotope record from the Verlorenvlei Estuary, South Africa. We assessed how leaf wax lipids, insoluble macromolecular organic matter, bulk C/N data and compound-specific stable carbon isotopes were linked to the site’s palynological record and to evidence for regional sea level and environmental change. Down-core trends in bulk δ13C are closely coupled to trends in pollen types from saline-tolerant taxa. These trends are mirrored by variations in the incorporation of reduced sulphur into macromolecular organic matter. This process, quantified with the thiophene ratio, is closely associated with periods of higher sea level 8,000–4,300 cal yr BP. We propose the thiophene ratio is a proxy for relative marine influence within (peri) estuarine sediments. All measured variables indicate differences between early-middle Holocene (8,000–4,300 cal BP) and late Holocene conditions at Verlorenvlei. The former period was more saline and preserves more labile macromolecular organic matter. Marine influence declined after 4,300 cal yr BP, and although the abundance of short-chain-length n-alkanes suggests continued presence of wetland flora until 2,500 cal yr BP, organic matter preservation became poorer and a drying trend was inferred, most notably for the interval 2,500–900 cal BP. Increasing freshwater inundation is apparent during the last 700 cal yr, consistent with several records from this region. Leaf wax n-alkane distributions are largely uncorrelated with bulk organic matter variables, with the exception of the abundance of C31 and C33 n-alkanes, which are negatively correlated with δ13CTOC. Furthermore, C31–C33 n-alkane δ13C values are uncorrelated with C23–C29 δ13C and δ13CTOC. They are also higher than our newly measured terrestrial (C3) vegetation C29 and C31 end-member values of −35 ± 2 and −34 ± 1 ‰, respectively. These patterns are best explained by a dominant contribution of local riparian vegetation to the C23–C29 n-alkanes, but time-varying contributions of non-local leaf waxes to the C31–C33 signals. This renders inferences concerning regional environmental change from long-chain leaf waxes potentially challenging in this setting.

Southern Africa supports a significant portion of the world's floral biodiversity but predicted changes in climate are likely to cause adverse impacts on the region's ecosystems and biodiversity. Knowledge regarding the resilience of vegetation cover is important for understanding the potential impact of anthropic or climatic change. The length of time vegetation cover takes to recover from disturbances can provide an indication of ecosystem resilience. We investigated spatial and temporal patterns in the persistence of vegetation cover across southern Africa (1982–2006) and used persistence probability plots to estimate decay times of NDVI trends as a means to characterise the potential resilience of key southern African biomes. Patterns of positive and negative NDVI trend persistence were spatially coherent, indicating collective dynamic behaviour of vegetation cover. Persistence probability plots indicated differences in resilience between biomes. Mean recovery times from negative NDVI trends were shorter than for positive trends in the Savanna and Nama Karoo, whereas the Succulent Karoo exhibited the shortest mean lifetime for positive NDVI trends and one of the longest mean lifetimes for negative trend survival, implying potentially slow recovery from environmental disturbance. The results show the potential of satellite-time series data for monitoring vegetation cover resilience in semi-arid regions.

International audience; The Cederberg Mountains (Western Cape Province, South Africa) are located within the Fynbos Biome, which exhibits some of the highest levels of species richness and endemism in the world. The region's post-glacial vegetation history, however, remains largely unknown. Presented here are high resolution pollen and microcharcoal records spanning the last 15,600 years obtained from the De Rif rock hyrax midden from the Driehoek Valley of the central Cederberg. In this region, previous pollen studies have shown muted variability in vegetation community composition during periods of globally marked climatic variability (e.g. the last glacial–interglacial transition). In our record, however, significant changes in vegetation composition are apparent. Most notably, they indicate a shift from ericaceous/restioid fynbos (present from 15,600 to 13,300 cal yr BP) to a brief, but prominent, development of proteoid fynbos at the beginning of the Holocene around 11,200 cal yr BP. This vegetation shift is associated with increased moisture at the site, and coincides with reduced fire frequency as indicated by the microcharcoal record. At 10,400 cal yr BP, there is a marked reduction in Protea-type pollen, which is replaced by thicket, characterised by Dodonaea, which became the dominant arboreal pollen type. This shift was likely the result of a long relatively fire-free period coupled with warmer and wetter climates spanning much of the early Holocene. A brief but marked decrease in water availability around 8500–8000 cal yr BP resulted in the strong decrease of Dodonaea pollen. The vegetation of the mid-to late Holocene is characterised by the increased occurrence of Asteraceae and succulent taxa, suggesting substantially drier conditions. These data give unprecedented insight into the vegetation dynamics across a period of substantial, rapid climate change, and while they confirm the presence of fynbos elements throughout the last 15,600 years, the results highlight significant fluctuations in the vegetation that were triggered by changes in both climate and fire regimes.

International audience; In southeast Africa – a region for which few palaeoenvironmental records are available – the fossil pollen record from the Wonderkrater spring mound has contributed substantially to our understanding of past vegetation change since the Last Glacial Maximum (LGM; 21 ka). Multivariate analysis of the pollen data by Scott and Thackeray (1987) provided environmental reconstructions suggesting relatively mesic LGM conditions, with warm and dry conditions during the early Holocene (11–6 cal kBP). This conforms to predicted patterns of precipitation change in the southern African tropics in response to Northern Hemisphere cooling and or-bital forcing. Subsequent data from the Cold Air Cave speleothems and a sea-surface temperature record from the Mozambique Channel, however, indicate that conditions during the early to mid-Holocene may have been wetter than present in the Wonderkrater region. To explore this question further, we have created a series of botanical–climatological transfer functions based on a combination of modern climate and plant distribution data from southern Africa. Applying these to the Wonderkrater fossil pollen sequence, we have derived quantitative estimates for temperatures during the cold and warm quarters, as well as precipitation during the wet and dry quarters. In addition, a species-selection method based on Bayesian statistics is outlined, which provided a parsimonious choice of likely plant species from what are otherwise taxonomical-ly broad pollen-types. We do not propose that our findings invalidate the previous principal component analyses, but they do have the advantage of being based more clearly on the relationship between modern plant distributions and individual climatic variables. Results indicate that temperatures during both the warm and cold seasons were 6 ± 2 °C colder during the LGM and Younger Dryas, and that rainy season precipitation during the Last Gla-cial Maximum was ~ 50% of that during the mid-Holocene. Our results also imply that changes in precipitation at Wonderkrater generally track changes in Mozambique Channel sea-surface temperatures, with a steady increase following the Younger Dryas to a period of maximum water availability at Wonderkrater ~ 3–7 ka. These findings argue against a dominant role of a shifting Intertropical Convergence Zone in determining long-term environmental trends, and indicate that the northern and southern tropics experienced similar climatic trends during the last 20 kyr.

International audience; Rock hyrax middens are important palaeoenvironmental archives in southern Africa. Carbon and nitrogen isotope measurements on middens (hyraceum) are key components of climate reconstructions, but their interpretations require refinement. Although d 15 N in hyraceum often correlates with independent proxies for palaeo-aridity, the impacts of dietary and physiological controls on hyraceum d 15 N remain to be resolved. We analyse d 13 C and d 15 N in plant foliage, hyrax faecal pellets and hyraceum from 21 sites across southern Africa. Faeces are generally depleted in 13 C (d 13 C typically < À20‰), suggesting significant browsing. Grazing is rarely dominant and probably occurs only when palatable grass is available. Variability in faecal and foliar d 15 N is large, but foliar d 15 N is positively correlated with faecal d 15 N. The diet-faeces d 15 N offset is uncorrelated with climate (aridity), but is correlated with %N in faeces. Faecal d 15 N is positively correlated with modern hyraceum d 15 N, and the relationships with aridity index for foliar and faecal (body tissue) d 15 N are comparable. These observations implicate diet as a significant control on hyraceum d 15 N and we observe no strong evidence for metabolic controls on hyraceum d 15 N. More data are required to refine these relationships, but these observations are consistent with current palaeoenvironmental interpretations of midden d 15 N and d 13 C.

Pyrolysis–gas chromatography mass spectrometry (py-GC/MS) allows the characterisation of complex macromolecular organic matter. In lakes and wetlands this can potentially be used to assess the preservation/diagenesis and provenance of sediment organic matter. It can complement palaeoenvironmental investigations utilising ‘bulk’ sediment variables such as total organic carbon (TOC) and TOC/total nitrogen ratios. We applied py-GC/MS analyses to a ~32,000-year sediment record from the southern Cape coastline of South Africa. We used the results to evaluate the sources and extent of degradation of organic matter in this semi-arid environment. Marked down-core changes in the relative abundance of multiple pyrolysis products were observed. Correspondence analysis revealed that the major driver of this down-core variability in OM composition was selective preservation/degradation. Samples comprising highly degraded OM are primarily confined to the lower half of the core, older than ~12,000 years, and are characterised by suites of low-molecular-weight aromatic pyrolysis products. Samples rich in organic matter, e.g. surface sediments, are characterised by products derived from fresh emergent or terrestrial vegetation, which include lignin monomers, plant-derived fatty acids and long-chain n-alkanes. Pyrolysates from the late glacial-early Holocene period, approximately mid-way down the core are characterised by distinct suites of long-chain n-alkene/n-alkane doublets, which may reflect the selective preservation of recalcitrant aliphatic macromolecules and/or enhanced inputs of the algal macromolecule algaenan/polymerised algal lipids. Increased TOC, lower δ13C and increased abundance of more labile lignin and fatty acid products at the same depths suggest this period was associated with increased lake primary productivity and enhanced inputs of terrestrial OM. TOC is the only ‘bulk’ parameter correlated with the correspondence analysis axes extracted from the py-GC/MS data. Distinct fluctuations in TOC/total nitrogen ratio are not explained by variation in organo-nitrogen pyrolysis products. Notwithstanding, the study suggests that py-GC/MS has potential to complement palaeolimnological investigations, particularly in regions such as southern Africa, where other paleoenvironmental proxy variables in sediments may be lacking or equivocal.

The continental margin of southern South Africa exhibits an array of emergent marginal marine sediments permitting the reconstruction of long-term eustatic sea-level changes. We report a suite of optical luminescence ages and supplementary amino acid racemization data, which provide paleosea-level index points for three sites on this coastline. Deposits in the Swartvlei and Groot Brak estuaries display tidal inlet facies overlain by shoreface or eolian facies. Contemporary facies relations suggest a probable high stand 6.0–8.5 m above modern sea level (amsl). At Cape Agulhas, evidence of a past sea-level high stand comprises a gravel beach (ca. 3.8 m amsl) and an overlying sandy shoreface facies (up to 7.5 m amsl). OSL ages between 138 ± 7 ka and 118 ± 7 ka confirm a last interglacial age for all marginal marine facies. The high stand was followed by a sea-level regression that was associated with the accumulation of eolian dunes dating to between 122 ± 7 ka and 113 ± 6 ka. These data provide the first rigorous numerical age constraints for last interglacial sea-level fluctuations in this region, revealing the timing and elevation of the last interglacial high stand to broadly mirror a number of other far-field locations.

This study examines two major late Quaternary coastal dune systems situated in the southwestern-most extremity of Africa. The False Bay and Duinefontyn dune plumes formed in close proximity, but under contrasting oceanographic regimes (warm Agulhas and cold Benguela oceanic current systems respectively). The False Bay and Duinefontyn dune plumes have hitherto lacked the objective, numerical chronology required to realize their full potential in unraveling the complex palaeo-oceanographic and palaeoclimatic history of the region. Here we present a dual amino acid racemizationn (AAR) and optically stimulated luminescence (OSL) chronological framework from the extensive three dimensional exposures in sea cliffs. At False Bay, three generations of dune deposition, corresponding with orbitally forced climatic/sea level cycles (MIS 7, MIS 5 and Holocene) were resolved, whereas the Duinefontyn Plume is dominated by MIS 5 and Holocene sedimentation. At False Bay and Duinefontyn, glacial periods are marked by the development of mature palaeosols, confirming the link between glacio-eustacy and dune deposition determined previously on the west and southern coasts of South Africa. Along the west coast dune plumes typify dunefield morphology, whereas shoreline-parallel dune cordons are commonly developed on the southern coast. These regional variations in dune system morphogenesis are largely controlled by contrasting wind and rainfall patterns. The attenuated dimensions of the MIS 5 plumes at False Bay and Duinefontyn may indicate a weakening of the South Atlantic Anticyclone during the Last Interglacial. At False Bay, stone artifacts illustrate a human presence in the region during MIS 7.

The impressive Pleistocene coastal aeolianite exposures in sea cliffs east of Still Bay on the west–southern coast of South Africa host a rich archive of fossil mammalian trackways, including the African elephant (Loxodonta africana). Neither the ichnofossils nor their host sediments have been described in any detail and chronologies remained uncertain. This paper presents a new optically stimulated luminescence (OSL) and amino acid racemisation (AAR) chronology (the first joint application of OSL/AAR dating in South Africa). This provides a temporal framework for assessing the palaeoenvironmental significance of dune sedimentation patterns, pedogenesis and ichnology. The Pleistocene aeolianite exposures at Still Bay represent the recently eroded remnants of a dune cordon, mainly built by coalesced parabolic dune systems. Sedimentary facies are dominated by large-scale planar cross-stratification formed by foreset progradation in the nose and trailing arms of the dunes and low-angle bedding, chiefly representing sedimentation in low relief interdune terrain. The main dune building wind regime was westerly, associated with cyclonic polar frontal systems (as at the present time). The OSL and AAR dating demonstrate ages ranging from MIS 5e to 5b and termination of Pleistocene aeolian sedimentation at ∼ 90 ka. The Pleistocene aeolianite is separated from the overlying Holocene dunes (dated to ∼ 8 ka), by a major hiatus recorded by a horizon of intense pedogenesis. Elephant footprints were seen in profile, as casts on the underside of beds and as natural impressions. The taphonomic processes controlling the morphology and preservation of these unique ichnofossils were found to be complex. The presence of Loxodonta africana at Still Bay represents the southernmost occurrence of this species recorded to date and possibly, a closer proximity of woodland during MIS 5. This and other observations may indicate a higher moisture regime than at present. There is no available evidence that the elephants were predated by contemporary Middle Stone Age people.

Located at the interface between the temperate westerly and sub-tropical climate systems, South Africa's winter rainfall zone (WRZ) is a key location in understanding Late Quaternary atmospheric circulation dynamics. Inactive eolian deposits in the WRZ, comprising pan-fringing lunette and coastal dunes, were investigated to establish their depositional ages and utility as paleoenvironmental indicators. The resulting optical luminescence chronology reveals episodic lunette accretion at 60,000–45,000 yr, 12,000–13,000 yr, 2800–2600 yr, 1200 yr, and Episodes of lunette and coastal dune accretion on the Agulhas Plain are temporally distinct, reflecting differing fundamental controls on their activity. Comparisons to previously published data also reveal that the lunettes differ in age from more ancient coastal eolianites. Lunette deposition is asynchronous between locations, reflecting the topographic and hydrological setting of the individual pans. In near-coastal settings, with limited surface recharge, lunette accretion appears to be at least partially controlled by sea level induced changes in groundwater levels. Those pans with more significant surface recharge (particularly from fluvial systems) may produce less ambiguous paleoenvironmental records, with pan status more strongly reflecting regional hydrological conditions. Lunette orientation is indicative of strong westerly winds during both the Pleistocene and Holocene. Lunette accretion would have been promoted by reduced on-shore moisture transport during the summer months, enhancing rainfall seasonality. Such conditions would have been promoted by increased continentality as the Agulhas Bank was exposed during low sea level stands.

Presented here are stable nitrogen isotope data from a rock hyrax (Procavia capensis) middens from northwestern Namibia that record a series of rapid aridification events beginning at ca. 3800 cal yr BP, and which mark a progressive decrease in regional humidity across the Holocene. Strong correlations exist between this record and other terrestrial and marine archives from southern Africa, indicating that the observed pattern of climate change is regionally coherent. Combined, these data indicate hemispheric synchrony in tropical African climate change during the Holocene, with similar trends characterising the termination of the ‘African Humid Period’ (AHP) in both the northern and southern tropics. These findings run counter to the widely accepted model of direct low-latitude insolation forcing, which requires an anti-phase relationship to exist between the hemispheres. The combined dataset highlights: 1) the importance of forcing mechanisms influencing the high northern latitudes in effecting low-latitude climate change in Africa, and 2) the potential importance of solar forcing and variations in the Earth's geomagnetic shield in determining both long-term and rapid centennial-scale climate changes, identifying a possible mechanism for the variations marking the AHP termination in both the southern and northern tropics.

Hyrax middens are unique environmental archives with the potential to provide unprecedented high-resolution palaeoenvironmental records, particularly in the arid regions of southern Africa. This study provides the first detailed characterisation of the organic matter composition of hyraceum and aims to identify biomarker evidence capable of providing new or supplementary palaeoenvironmental data from these novel archives. Pyrolysis gas chromatography mass spectrometry reveals hyraceum to be dominated by nitrogen-containing aromatic compounds, notably benzamide. This is almost certainly derived directly from the hyrax urine and is probably the main source of nitrogen as measured in bulk δ 15 N measurements. Solvent-extractable lipids comprise homologous suites of long-chain n -alkanes (C 24 –C 34 ) and n -alkanols (C 16 –C 26 ), characteristic of higher plant leaf waxes, along with an abundance of animal-derived sterols, higher plant sterols and terpenoids; as well as the ubiquitous benzamide. n -alkane distributions and compound specific δ 13 C clearly differentiate samples from the C 3 vegetation dominated Cape Floristic Region, and the more arid, C 4 grass-rich savannas of central Namibia (Klein Spitzkoppe). Distinct changes in n -alkane distribution and δ 13 C are observed within the Spitzkoppe midden; most notably the mid to late Holocene period (c. 6000–2000 cal yr BP), which records a progressive reduction in grass-derived organic matter inputs. Based on the animal's feeding behaviour and contemporary site ecology, a phase of increasing aridity is inferred, which is consistent with other proxy data from this site (e.g. bulk δ 15 N). The excellent preservation of plant and animal biomarkers suggests that there is significant potential for midden-derived biomarkers to provide long-term palaeoenvironmental proxies.