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This paper presents results of a multidisciplinary research initiative examining human responses to environmental change at the intersection of the southern coastal plain of the Caspian Sea and the foothills of the Alborz Mountains during the terminal Pleistocene and early Holocene. Our palaeo-environmental analysis of two sedimentary cores obtained from a lagoon in close proximity to four caves, occupied by human groups during the transition from hunting and gathering to food-producing ways of life in this region, confirms Charles McBurney's 1968 hypothesis that when Caspian Sea levels were high, Mesolithic hunters were reliant on seal and deer, but as water levels receded and a wide coastal plain emerged, hunters consumed a different range of herbivorous mammalian species. Palynological evidence obtained from these two cores also demonstrates that the cool and dry climatic conditions often associated with the Younger Dryas stadial do not appear to have been extreme in this region. Thus, increasingly sedentary hunting and gathering groups could have drawn on plant and animal resources from multiple ecological niches without suffering significant resource stress or reduced population levels that may have been encountered in neighbouring regions. Our analyses of botanical, faunal and archaeological remains from a recently-discovered open-air Mesolithic and aceramic Neolithic site also shows an early process of Neolithization in the southern Caspian basin, which was a very gradual, low-cost adaptation to new ways of life, with neither the abandonment of hunting and gathering, nor a climatic trigger event for the emergence of a low-level, food-producing society.

The Dampier Archipelago (including the Burrup Peninsula), now generally known as Murujuga, is a significant rock art province in north-western Australia which documents the transition of an arid-maritime cultural landscape through time. This archipelago of 42 islands has only existed since the mid-Holocene, when the sea level rose to its current height. Previous excavations across Murujuga have demonstrated Holocene occupation sequences, but the highly weathered rock art depicting extinct fauna and early styles suggests a far greater age for occupation and rock art production. The archaeological record from the Pilbara and Carnarvon bioregions demonstrates human occupation through 50,000 years of environmental change. While the regional prehistory and engraved art suggests that people were producing art here since they first occupied these arid rocky slopes, no clear evidence of Pleistocene occupation has been found across Murujuga, until now. Murujuga Rockshelter (MR1) reveals that occupation of this shelter began late in the Last Glacial Maximum, when the Murujuga Ranges would likely have served as one of a network of Pilbara refugia. In the terminal Pleistocene/Early Holocene, and likely in tandem with the last stages of sea level rise, the proportion of artefacts manufactured on exotic lithologies declines sharply, revealing a changed foraging range and increasing territorial focus in this period of increased demographic packing as the coastline advanced. Abandonment of the site as early as 7000 years ago is indicated, suggesting a changing resource focus to the increasingly proximal coastline. This paper provides the first evidence of how Aboriginal people adapted their Pleistocene procurement strategies in response to significant environmental and landscape changes in Murujuga. This changing logistical strategy provides an explanation for the increased rock art production in the terminal Pleistocene/Early Holocene.

The Late Upper Palaeolithic of Europe, particularly the Last Glacial Maximum (LGM: 26-19 kyr cal BP), was a time of dramatic climatic changes. Fauna, and the humans that preyed on them, were forced to adapt their behaviours in response to climate changes to survive. The Cantabrian Region of northern Spain was continuously inhabited during this period when many other areas of Europe were inhospitable. The site of Las Caldas (Asturias) was repeatedly occupied by hunter-gatherers during the Solutrean (26.1–20.3 kyr cal BP) and Magdalenian (18.5–14.3 kyr cal BP). This paper uses δ13C and δ15N stable isotope analysis of red deer (Cervus elaphus) and Spanish ibex (Capra pyrenaica) remains to reconstruct past environments, ungulate niches and habitats, and to understand how this impacted on their availability as a prey source. Results show that during the Solutrean, cold and potentially wet LGM conditions were experienced and ibex lived in lower altitudes, likely due to reduced vegetation, and even small glaciers on the higher mountain slopes. Improved environmental conditions in the Magdalenian allowed ibex to live in their preferred habitat of higher altitudes. Ameliorated Late Glacial conditions correspond with changing economic hunting strategies at the site. Humans exploited wider ecological zones, over larger distances, which coincides with population growth, and greater connectivity across the Cantabrian region. This research highlights the importance of characterising the complex interactions between humans, animals and environments during the Late Pleistocene and how they responded to rapidly changing environmental conditions.

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.

International audience; 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.

This paper reviews recent progress in the use of linear dunes as ‘geoproxies’ of late Quaternary environmental change, summarises the challenges facing their use, and explores some potential solutions to these challenges. Large areas of the swathes of linear dunes which occupy the continental interior of southern Africa, Australia, and parts of central Asia and southern America currently have limited or negligible aeolian activity. They have been recognised as offering potential information about past environments for more than a century, but only with the widespread application of luminescence dating during the 1990s did they realistically start to offer the prospect of being an extensive, dateable proxy of late Quaternary palaeoenvironments and, possibly, palaeoclimates. Dating aeolian dune sands with luminescence methods is generally (although not always) relatively straightforward. Over the past twenty years, a large number (>1000) of luminescence ages have been added to the global dataset, yet there has also been significant criticism of some of the rationale underpinning much of the interpretation of the records derived. At the landscape scale, developments of arguably equal importance have come from improved geomorphological understanding based on the wider availability of remotely-sensed data and the paradigm of dunefield evolution as a self-organising complex system. Current challenges are identified in three key regions: incomplete understanding of how the process geomorphology of linear dunes affect the accumulation and preservation of sediment, a lack of clarity regarding the temporal and spatial scale of the response in a dynamic environmental setting and uncertainty surrounding the drivers of changing rates of net accumulation. Solutions to these challenges lie within diverse research methodologies. Certainly, further field study is required, with improvement required in understanding system responses to changing environmental stimuli at scales from sedimentological to landscape. In parallel, the full implications of complex systems approaches to aeolian geomorphology for linear dunes lag behind the adoption of the concept to some other dune forms (e.g. barchans); the relationship between observed dune complexity and age from field data complicates previous suggestions that dune patterning may be purely a function of development time. Parallel to this lies the need to improve interpretation of the results of dune geochronological studies; a suggestion is offered which aims to test the statistical significance of dune accumulation time-series by comparison with a modelled system with unchanging external forcing. Despite the initial promise of linear dune records as a revolutionary source of palaeoenvironmental information in drylands, the outcomes to date have been coarse, although still valuable, in resolution. Perhaps the most valuable realization has been that geomorphological understanding of these widespread landforms is incomplete.

There is a current need to develop annual/decadal chronologies from periods of rapid climate change in order to understand the rate and timing of climate events and identify how other proxies either lead or lag this climate forcing. Annually-laminated or varved sediments are key proxies for understanding environmental change at such a scale. This paper presents the results of microscale analysis of glaciolacustrine varve sediments from Scotland and develops a new index called varve group, which ranks the number of pulses of sediment observed in the summer component of the varve. The varve group index is compared with data from the Greenland ice-core record and correspondence can be observed between the oxygen isotope records from Greenland during the latter part of GS-1 and the 515-year Lochaber varve group index. The processes that control the number of sediment pulses into the lake basin are discussed and we examine how these factors might control both the isotopic composition of the ice cores and varve group formation. It is proposed that the position of the sea ice in the North Atlantic may provide such a mechanism.

Precisely how Upper Palaeolithic human ecology was shaped by changing climate during the Pleniglacial remains a matter of debate, for while this generally cold period is now understood to include complex and often rapid flux in climate, there are still considerable difficulties in resolving climatic variations at particular times and places — derived from various lines of proxy evidence — with the high-resolution proxy record of temperature changes from oxygen isotope analysis of the Greenland ice-cores. In this paper we apply the methodology of large-scale flotation to newly excavated contexts from the Upper Palaeolithic (Gravettian) site of Dolni Vĕstonice II, Czech Republic, to explore the potential of charcoal — as a natural archive of environmental information — to offer information on environmental change towards the end of the middle pleniglacial during Oxygen Isotope Stage 3, between c. 32,500 and 31,200 Cal yr BP. The results of an analysis of ring widths and other anatomical features — interpreted alongside micromorphological data — indicate that this charcoal may capture a higher-resolution record of the changing climatic conditions during which humans were first expanding into these hitherto marginal ecologies and, consequently, shed new light upon the complexity of the lifeways that enabled them to do so.

The present paper analyses the evidence provided by three sites (Sima del Elefante, Gran Dolina, and Galeria) located in the Trinchera del Ferrocarril of the Sierra de Atapuerca. These three sites are cave infillings that contain sediments deposited from approximately 1.2 Ma to 200 kyr. Pollen, herpetofauna, and small and large mammal remains are used as proxies to obtain a general picture of the environmental changes that occurred at the Sierra de Atapuerca throughout the one million-year period represented at these sites. Similarly, cultural changes are tracked analyzing the evidence of human behavior obtained from the study of several bone and lithic assemblages from these three sites. At least three periods with different cultural features, involving technology, subsistence and behavior, are determined from the available evidence. The first two periods correspond to the Mode 1 technology and Homo antecessor: the first is dated around 1.2 to 1.0 Ma and reflects opportunistic behavior both in technology and subsistence. The second period is around 800 kyr BP. Mode 1 technology is still maintained, but subsistence strategies include systematic hunting and the use of base camps. The third period is dated between 500 ka and 200 ka and corresponds to the Mode 2 technology and the acquisition of directional hunting and other organizational strategies by Homo heidelbergensis. A transition from Mode 2 to Mode 3 seems to appear at the end of this time-range, and may reflect the early phases of a fourth cultural change. With regard to the environment, our main conclusion is that there was an absence of extremely harsh conditions at Atapuerca throughout this time period. The presence of Mediterranean taxa was constant and the dominant landscape was a savannah-like open environment, probably with small forest patches. An alternation of Mediterranean and mesic species as the dominant component of the tree storey was induced by the climatic cycles, and steppes spread across the landscape during the drier periods. In any case, it is not possible to establish clear cut-off points separating entirely different environmental episodes. Our results show no evidence of any relationship between environmental change and cultural change at the Sierra de Atapuerca.

The dispersal of the genus Homo occurred against a background of continuous environmental change. Here, dispersals of large mammals through the Levantine Corridor and into Western Europe and Java are studied and compared to existing records of climatic change and dispersals of early humans and lithic industry. The first human dispersal (with Oldowan lithic industry) out of Africa, around or shortly before 1.8 Ma may have been triggered by biological evolution and increased social organisation, rather than environmental change. After that event, increasing aridity led to decreased faunal exchange between Africa and Eurasia and may have isolated the human populations of Africa and Africa. Southern (Java) and Eastern Asia (China) also seem to have been isolated. Human dispersal into Western Europe may have been limited by closed environments in Central Europe until about 1.2 Ma ago, when faunal dispersal into Europe suggests the cyclic spread of open environments to the west. Acheulean technology originated in Africa, some 1.6-1.5 Ma ago, but its dispersal into Eurasia may have been obstructed by an arid Southwest Asia, until broadly about 0.9 Ma ago, when faunal exchange suggests that the area became temporarily less dry. By 0.6-0.5 Ma ago it reached Europe. © 2010 Elsevier Ltd., This paper benefited from discussions with members of the Atapuerca team and many others, particularly John de Vos. The results on biogeography presented here are a contribution to projects BOS2003-08938-C03-02 and CGL2008-03881 of the Ministerio de Ciencia y Inovación and NL-TAF-4053 of Synthesys.

In contrast to well-studied paleoenvironments of Plio-Pleistocene hominin sites in East Africa, little is known about the ecology of the earliest North African human occupation sites. The recent studies at Ain Hanech and El-Kherba in northeastern Algeria have broadened the range of Plio-Pleistocene hominin ecology to include the earliest known archaeological sites documented in North Africa. Ain Hanech and El-Kherba are significant for yielding savanna-like faunas associated with Oldowan stone tools dated back to approximately 1.8 million years ago. This paper focuses on reconstructing the ecology of Ain Hanech and El-Kherba based on excavated faunas and stable carbon isotope of pedogenic carbonates from El-Kherba stratigraphic profile. The results point out to an overall open paleolandscape and a C3 predominantly paleovegetation both woody and grasses. In addition, the stable-carbon-isotopic evidence shows a clear environmental change through time at El-Kherba, which likely impacted hominin foraging activities in level A.

This paper contributes to the emerging picture of late Pleistocene and Holocene environmental change in the Bonneville basin, western North America, through analysis of pollen and sediments from the Blue Lake marsh system, a major wetland area located on the western margin of the Great Salt Lake desert. Analyses of data obtained from the upper 4 m of the Blue Lake core suggest that during the latest Pleistocene, when Lake Bonneville covered the Blue Lake site, pine and sagebrush dominated terrestrial plant communities. These steppe-woodland taxa declined in abundance after ∼12 cal ka BP. Wetland plant communities developed at or nearby Blue Lake by ∼11.9 cal ka BP and bulrush-dominated marshes were established no later than 10.8 cal ka BP. The Blue Lake wetlands largely desiccated during a dry and warm early middle Holocene ∼8.3–6.5 cal ka BP. Climatic amelioration starting ∼6.5 cal ka BP is marked principally by a local return of marshes at the expense of playa and grass meadow communities, and a regional increase in sagebrush relative to other dryland shrubs. Singleleaf pinyon pine migrated into the nearby Goshute Mountains after ∼8 cal ka BP. Late Holocene fluctuations include cool intervals from ∼4.4 to 3.4 and ∼2.7 to 1.5 cal ka BP and warmer conditions from 3.4 to 2.7 cal BP and after 1.5 cal ka BP.

This paper documents the first Holocene palaeoecological record for the Okavango Delta, northwest Botswana. Sedimentological, stable carbon isotope and palynological data, supported by conventional and AMS radiocarbon assays, are presented from coring sites at Gauxa Lagoon and the Ncamasere and Tamacha valleys along the western margin of the Okavango Panhandle. Earliest Holocene vegetation patterns are not readily distinguished at the three sites, owing to poor pollen preservation conditions. A wet phase or period of enhanced Okavango flooding is tentatively identified around 9000 BP on the basis of increased accumulation of organic matter within floodplain sediments. Palynological and sedimentological data, combined with stable carbon isotope analyses, suggest that relatively dry conditions extended from 7000 to 4000 BP (punctuated by a wet phase at around 6000 BP). This is interpreted as indicating reduced rainfall over the Okavango headwaters in Angola. Conditions from around 4000 BP became progressively wetter, initially in response to increased water throughputs via the Okavango system. Wettest conditions occurred from 2300 to 1000 BP due to a combination of increased regional rainfall and raised Okavango flood levels. Conditions approach those of the present day after this time. A major shift from grass- to sedge-dominated vegetation communities, apparent at all three sites in the past thousand years, is attributed to anthropogenic disturbance. These changes are subsequently discussed in light of regional continental and marine palaeoenvironmental records, and the implications for the future management of the Okavango River considered.

Few terrestrial archives offer multi-proxy information with temporal and spatial coverage comparable to marine palaeo-records. Pollen assemblages that are preserved in terrestrial sedimentary systems are, however, one such source. They offer palaeoecologists an archive from which to gain insight into past environmental change and associated vegetation dynamics, typically extending back many thousands of years. Recent preliminary results from the stable isotopic analyses of raw and extracted pollen exina suggest that significant potential exists to utilise palaeo-pollen records as quantitative indicators of past terrestrial palaeoenvironmental change over medium- to long-timescales. Moreover, by combining isotopic analyses with conventional pollen assemblages the information available is greatly enhanced, especially regarding the relative timing of plant community response to external forcing. In this paper, we review the limited number of studies that have investigated the isotopic analysis of pollen and we highlight the difficulties and current limitations that are involved. We propose some possible solutions to the methodological issues raised and discuss recent findings of a pilot study of the carbon, hydrogen and oxygen isotopes in raw pollen grains collected from a network of north European sites.

This paper reviews the various Late Quaternary records that are available from western Egypt and northern Sudan, which includes more than 500 published radiocarbon dates and various sedimentary archives from local landscape components, including palaeolakes, soils, drainages (wadis), and archaeological sites. This palaeoenvironmental compilation frames the spatial and temporal context of local cultural activities when the region was most hospitable ∼9000–6000 BP; at this time, monsoonal weather influenced the portion of the African continental interior, creating enough convective rainfall for occasional surface water storage. In this part of the modern Sahara, rapid hydroclimatic changes play a key role in geomorphic evolution and resource availability. As ‘watering holes’ formed and dried up in the Early to Middle Holocene, Neolithic people developed various subsistence strategies, including opportunistic hunting of small animals (e.g. gazelle and hare), and food-related (e.g. wild sorghum, millet, and legumes) activities: gathering, plant cultivation and livestock-rearing. During its wettest phases during the ‘monsoonal maximum,’ the area was drought-prone, sustaining a meager steppe–shrub desert flora. Further desertification and aeolian deflation during the Middle and Late Holocene fostered technological innovation, migration and settlement, as well as the further development of agrarian communities and complex culture.

Climate changes over the Holocene have directly impacted on both coastal processes and human use of coastal areas. This paper presents results from the dating of wind blown sand deposits collected from coastal and archaeological sites in Northern Scotland. Archaeological remains are frequently found interspersed with sand deposits and represent distinct periods of occupation of settlement sites within the local landscapes. In some cases storm events sufficiently inundate the sites with sand to result in periodic abandonment. Storm events can also have dramatic results on adjacent rock coastlines, with storm boulder ridges emplaced by large waves, burying sand deposits on cliff-top sites. Work has been undertaken using a quartz SAR protocol to date sand deposition at two archaeological sites in Orkney and a cliff-top site in Shetland. These dates provide chronological information, which help to construct regional chronologies of climatic instability and environmental change and allow the SAR-OSL method to be assessed as an accurate sediment dating tool in this context.

This paper examines the Late Quaternary (c. 20,300–

Palaeoecologists are increasingly using close interval or continuous sampling of lake sediments to construct fine resolution records of environmental change. The degree of temporal resolution sought in these studies is typically decades or years. The use of lake sediments for such fine resolution reconstructions assumes that temporal mixing of the sediments is negligible. In this paper we examine the physical and biological processes that cause sediment mixing in small lakes. We use physical models and empirical data to develop a set of heuristics relating lake depth and area to sediment mixing by slumping, waves, currents and bioturbation. We also develop a heuristic that allows information on lake depth and area to be used to determine if the sediments of a lake will likely be massive or annually laminated. In general, the degree of sediment mixing likely to occur in a small lake is directly related to the depth and surface area of the lake. However, each of the agents of mixing has a different critical relationship with lake depth and surface area. We present a series of equations and a summarizing figure that, based on lake surface area and maximum depth, allows the type of thermal stratification (polymictic, dimictic or meromictic) and the degree of sediment mixing present in the lake to be inferred.

The study of Quaternary environmental change is directly applicable to on-going issues of global conservation. Palaeoecological research techniques provide the tools to address some of the key questions presently being asked by conservation ecologists and land management organizations. But is this type of analysis currently being utilized to its full potential? Are the results of palaeoenvironmental analyses routinely applied to practical issues of natural resource management, and if not what can be done to expand the application of this research within the conservation community? This paper reviews recent developments in the application of the analysis of late Quaternary environmental change to key environmental issues of biodiversity and conservation management and examines areas which could be strengthened in the future including: (i) determination of baselines and natural ecosystem variability; (ii) understanding ecological thresholds and resilience; (iii) climate change conservation strategies; (iv) biological invasions; and (v) conservation and culture. © 2008 Elsevier Ltd. All rights reserved.