Ian Candy

The earliest record of human activity in northern Europe

The colonization of Eurasia by early humans is a key event after their spread out of Africa, but the nature, timing and ecological context of the earliest human occupation of northwest Europe is uncertain and has been the subject of intense debate. The southern Caucasus was occupied about 1.8 million years (Myr) ago, whereas human remains from Atapuerca-TD6, Spain (more than 780 kyr ago) and Ceprano, Italy (about 800 kyr ago) show that early Homo had dispersed to the Mediterranean hinterland before the Brunhes–Matuyama magnetic polarity reversal (780 kyr ago). Until now, the earliest uncontested artefacts from northern Europe were much younger, suggesting that humans were unable to colonize northern latitudes until about 500 kyr ago. Here we report flint artefacts from the Cromer Forest-bed Formation at Pakefield (52° N), Suffolk, UK, from an interglacial sequence yielding a diverse range of plant and animal fossils. Event and lithostratigraphy, palaeomagnetism, amino acid geochronology and biostratigraphy indicate that the artefacts date to the early part of the Brunhes Chron (about 700 kyr ago) and thus represent the earliest unequivocal evidence for human presence north of the Alps.

Early and early Middle Pleistocene river, coastal and neotectonic processes, southeast Norfolk, England

This paper investigates the interaction between coastal and river processes and neotectonics, prior to glaciation of northern East Anglia, eastern England. The study is based on results obtained from two boreholes drilled into the plateau of southeast Norfolk, between the Yare and Waveney valleys. Diagnostic sedimentary and lithological indicators from core samples are used to describe the main lithological units, and to compare them with the type sites of the Norwich Crag, and members of the Bytham Sands and Gravels, and Corton Formation. The results provide evidence for coastal sedimentation in the Early Pleistocene, when the Norwich and Wroxham Crags were deposited, and evidence to establish links between the coastal deposits and the contemporary river systems. The Norwich Crag received only suspended sediment from low energy rivers, whereas the Wroxham Crag received bedload transported from the whole catchment. Neotectonic subsidence within the region is proposed to explain the transgression of the Wroxham Crag across the Norwich Crag. The succeeding stratigraphical units are fluvial sediments of the Bytham river, which was the major river draining Midland England during the Middle Pleistocene. These sediments are located in a valley cut into the Crag, indicating uplift between the deposition of the coastal and river deposits. After their deposition, the whole region was overridden by glaciers that deposited the sediments of the Corton and Lowestoft formations, and shifted the Bytham river to a more southerly route.

Early and Middle Pleistocene river systems in eastern England: evidence from Leet Hill, southern Norfolk, England

Pleistocene sediments at Leet Hill, southern Norfolk are examined in terms of their sedimentary structures, palaeocurrent indicators, clast and heavy mineral lithology and litho- and morphostratigraphic position. Colour of the quartzite and vein-quartz clasts is used to differentiate the Bytham and the Kesgrave sands and gravels, with the Bytham sands and gravels having a significantly higher proportion of coloured material. The Kirby Cane sands and gravels are the lower sedimentary unit and were deposited by the Bytham river, which drained a catchment extending into central England. At Leet Hill, erosion of the Kesgrave Sands and Gravels by the Bytham river has given the Kirby Cane sands and gravels a distinctive lithological assemblage. Trace clast lithologies suggest that the Kesgrave Sands and Gravels in the region of Leet Hill were deposited in a coastal location with an input from northern sources as well as southern and Welsh sources diagnostic of the Thames catchment. The glaciofluvial Leet Hill Sands and Gravels were deposited by outwash from the Anglian Scandinavian ice sheet. Initially the flow direction of the outwash was determined by the Bytham river valley, but this changed to a southerly direction once the valley had been infilled. This paper provides the first indication of the location of the boundary (Early Pleistocene coastline) between the fluvial Kesgrave Sands and Gravels and the marine equivalent reworked by coastal processes, and demonstrates the way the pre-glacial relief initially controlled patterns of glaciofluvial sedimentation during the early part of the Anglian glaciation. Copyright

Formation of a rhizogenic calcrete during a glacial stage(Oxygen Isotope Stage 12): its palaeoenvironmental stratigraphic significance

The morphology and micromorphology of a carbonate-cemented horizon within Anglian Stage, Oxygen Isotope Stage (OIS) 12, glaciofluvial outwash deposits at Leet Hill, southern Norfolk are characteristic of a rhizogenic calcrete. The horizon consists of a laterally continuous calcified root mat and an associated vertical rhizolith, both of which contain micro-fabrics typical of biologically precipitated carbonate, i.e. needle fibre calcite, calcified root cells and pelleted micrite. Formation of this calcrete is suggested to relate to the coincident occurrence of a phase of land surface stability and a period of climatic amelioration within the Anglian Stage during which permafrost decayed, a near-surface water table formed and a vegetation cover became established. The period of calcrete formation is tentatively correlated with other evidence for a climatic amelioration during the Anglian Stage in eastern England. The stratigraphic position of the calcrete suggests that this amelioration occurred after the Scandinavian ice had advanced into East Anglia but prior to the overriding of the region by the British ice mass. The discovery of this calcrete represents the first known description of a rhizogenic calcrete from a glacial stage. It presents the possibility that other, previously unstudied, carbonate horizons within Quaternary deposits of northwest Europe may in fact be calcretes and that these may provide further palaeoenvironmental and stratigraphic information.

The Glacial History of the British Isles during the Early and Middle Pleistocene: Implications for the long-term development of the British Ice Sheet

Abstract We review the evidence for Quaternary glaciation in the British Isles and adjoining seas. Attention is given to the types of onshore and offshore evidence and the robustness of these evidence sources. We find evidence for onshore lowland glaciation during Marine Isotope Stages 16, 12, 10, 6 and 2.

Evidence for Middle Pleistocene temperate-climate high sea-level and lowland-scale glaciation, Chapel Hill, Norwich, UK

This paper reports a succession of Middle Pleistocene deposits from Chapel Hill south of Norwich in central Norfolk, eastern England. From the base upwards, sands and gravels with interbedded silts and clays, laminated clays and sandy diamicton, well-sorted sands with marine shells and foraminifera, and chalky diamicton are recorded overlying Chalk bedrock within a height range of c . 18–29 m OD. These units are interpreted on the basis of sedimentary, structural and lithological analysis as shallow-marine Wroxham Crag, Corton Till Member of the Happisburgh Formation, a newly defined shallow-marine Chapel Hill sands, and till of the Lowestoft Formation. The Chapel Hill sands contain foraminiferal assemblages that suggest temperate-water, then cold-water climate conditions and the high level of the deposits indicates small global ice volumes. The elevation of these deposits in terms of known global sea-level for the time also indicates uplift of the region since the period of deposition. The presence of these shallow-marine deposits between the tills of the Happisburgh and Lowestoft formations provides evidence that the Happisburgh Glaciation and the Anglian Glaciation were separated by non-glacial conditions.

Climates of the early Middle Pleistocene in Britain: Environments of the Earliest Humans in Northern Europe

Long-term climate records such as SPECMAP and EPICA imply that the early Middle Pleistocene (Marine Isotope Stages 19–13, 780–450 ka) was characterised by low magnitude climate cycles relative to the extreme glacial/interglacial cycles of the last 450 ka. As the early Middle Pleistocene is the period during which the first known occupation of Britain occurred, understanding the nature of climate cycles in northwest Europe during this period is important. In order to develop a clearer understanding of the pattern of climate change during the early Middle Pleistocene, deposits of this period are divided into four groups that are based on the climatic proxy data they contain. Group 1 deposits are characterised by evidence for interglacial climates that were warmer than the present day. Group 2 deposits are characterised by evidence for interglacial climates that were consistent with the present day with respect to their degree of warmth. Group 3 deposits contain evidence for temperate climates that were cooler than the present day; such deposits possibly reflect the end of an interglacial or interstadial. Group 4 deposits record evidence for extreme climate cooling and widespread permafrost development. This categorisation indicates that during multiple glacial/interglacial cycles the climate of eastern England oscillated between periods that were warmer than the present day, sometimes ‘Mediterranean’ in character, through to periods that were characterised by extreme climate cooling and widespread periglaciation. Despite the climate patterns suggested in the SPECMAP and EPICA records, there is no recognisable difference between the pattern of climate forcing observed in Britain during the early Middle Pleistocene relative to that which occurred during the late Middle and Late Pleistocene. Early human colonisers in Britain during the early Middle Pleistocene were, therefore, subjected to the same extremes of climate as humans during the last 450 ka. Consequently, it is probable that the pattern of depopulation during glacials and recolonisation during interglacials, proposed for the last four glacial cycles, is also likely to be true for the period 780–450 ka. It is also important to recognise that lithic artefacts are found in association with all four climatic groups, indicating that the presence of humans during the early Middle Pleistocene was not restricted to the climatic peaks of interglacials.

Palaeoenvironments of Ancient Humans in Britain: The Application of Oxygen and Carbon Isotopes to the Reconstruction of Pleistocene Environments

Abstract Stable oxygen and carbon isotopes in continental carbonates are used routinely as palaeoenvironmental proxies in Quaternary sequences. In the British Quaternary record, this approach has been relatively under-utilised despite the abundance of a wide variety of carbonate types, including soil and groundwater precipitates, tufa, freshwater and terrestrial mollusc shells and lacustrine carbonates. As part of the Ancient Human Occupation of Britain project, the potential of this approach for understanding the climates and environments of early humans in Britain has been investigated. These studies involved two stages: (1) the analysis of modern carbonates to understand how the stable isotope composition of these materials record modernenvironmental conditions; and (2) the application of these modern analogue studies to the investigation of carbonates from a number of British interglacial episodes. The application of this technique is discussed with reference to two archaeologically significant periods, the Cromerian Complex and the Hoxnian. These examples highlight the potential for using this technique to understand temperatures in past interglacials. The chapter concludes by discussing the significance of these studies to understanding the environments of human occupation.

Homo sapiens in Arabia by 85,000 years ago

Understanding the timing and character of the expansion of Homo sapiens out of Africa is critical for inferring the colonization and admixture processes that underpin global population history. It has been argued that dispersal out of Africa had an early phase, particularly ~130–90 thousand years ago (ka), that reached only the East Mediterranean Levant, and a later phase, ~60–50 ka, that extended across the diverse environments of Eurasia to Sahul. However, recent findings from East Asia and Sahul challenge this model. Here we show that H. sapiens was in the Arabian Peninsula before 85 ka. We describe the Al Wusta-1 (AW-1) intermediate phalanx from the site of Al Wusta in the Nefud desert, Saudi Arabia. AW-1 is the oldest directly dated fossil of our species outside Africa and the Levant. The palaeoenvironmental context of Al Wusta demonstrates that H. sapiens using Middle Palaeolithic stone tools dispersed into Arabia during a phase of increased precipitation driven by orbital forcing, in association with a primarily African fauna. A Bayesian model incorporating independent chronometric age estimates indicates a chronology for Al Wusta of ~95–86 ka, which we correlate with a humid episode in the later part of Marine Isotope Stage 5 known from various regional records. Al Wusta shows that early dispersals were more spatially and temporally extensive than previously thought. Early H. sapiens dispersals out of Africa were not limited to winter rainfall-fed Levantine Mediterranean woodlands immediately adjacent to Africa, but extended deep into the semi-arid grasslands of Arabia, facilitated by periods of enhanced monsoonal rainfall.A directly dated Homo sapiens phalanx from the Nefud desert reveals human presence in the Arabian Peninsula before 85,000 years ago. This represents the earliest date for H. sapiens outside Africa and the Levant.

Interglacial climates: Advances in our understanding of warm climate episodes

The Quaternary is characterized by the alternation of relatively brief periods of temperate climate (interglacials) with episodes of extreme cold, often with the build-up of extensive continental ice sheets. Over the last decade, new research has revealed far greater complexity and diversity in the interglacial record than previously recognized, with temperate-climate episodes of markedly different duration, stability and intensity. These findings not only shed light on the climatic parameters behind changing floras and faunas during the Pleistocene but also aid our understanding of climatic evolution during the Holocene (the current interglacial), in particular the search for the most appropriate past analogues. In this progress report, we review the basis for interglacial complexity, drawing upon the evidence from long continuous terrestrial records in the Mediterranean, Antarctic ice cores and river terrace sequences in western Europe, before using the details of the British Quaternary interglacial record as an example of how marine and terrestrial records can be linked.