Adrian G. Parker

The Southern Route “Out of Africa”: Evidence for an Early Expansion of Modern Humans into Arabia

Artifacts in eastern Arabia dating to 100,000 years ago imply that modern humans left Africa early, as climate fluctuated. The timing of the dispersal of anatomically modern humans (AMH) out of Africa is a fundamental question in human evolutionary studies. Existing data suggest a rapid coastal exodus via the Indian Ocean rim around 60,000 years ago. We present evidence from Jebel Faya, United Arab Emirates, demonstrating human presence in eastern Arabia during the last interglacial. The tool kit found at Jebel Faya has affinities to the late Middle Stone Age in northeast Africa, indicating that technological innovation was not necessary to facilitate migration into Arabia. Instead, we propose that low eustatic sea level and increased rainfall during the transition between marine isotope stages 6 and 5 allowed humans to populate Arabia. This evidence implies that AMH may have been present in South Asia before the Toba eruption (1).

A review of the mid-Holocene elm decline in the British Isles

Over the past 50 years the most enigmatic feature of pollen diagrams from northwest Europe has been the mid-Holocene ‘elm decline’, and there has been much speculation as to the origin(s) and cause(s) of this event. A total of 150 radiocarbon dates from 139 sites spanning the elm decline in Britain and Ireland have been collated and scrutinized. Statistical analyses on 138 dates show that the event has a mean date of 5036 14C yr BP with a standard deviation of ± 247. Calibration of the dates and combining the sum probabilities yielded a range spanning 6347-5281 cal yr BP (1s), covering 1066 years. The start of the elm decline event lies between 6343 and 6307 cal yr BP (1s), a period of 36 years, indicating that the onset was rapid. The end of the event lies between 5290 and 5420 cal yr BP (1s), a period of 130 years. The probability distribution indicates that the elm decline was a uniform phased event across the British Isles. It appears that the elm decline can be explained to a large extent by the outbreak of disease. However, recent research on palaeoclimatic change and the nature of the transition from the Mesolithic to Neolithic in the British Isles suggests that both climatic change and human activities were implicated. It was probably the interplay between these factors, rather than any in isolation, that catalyzed the widespread, catastrophic decline of elm populations during the mid-Holocene.

Hominin dispersal into the Nefud Desert and Middle palaeolithic settlement along the Jubbah Palaeolake, Northern Arabia.

The Arabian Peninsula is a key region for understanding hominin dispersals and the effect of climate change on prehistoric demography, although little information on these topics is presently available owing to the poor preservation of archaeological sites in this desert environment. Here, we describe the discovery of three stratified and buried archaeological sites in the Nefud Desert, which includes the oldest dated occupation for the region. The stone tool assemblages are identified as a Middle Palaeolithic industry that includes Levallois manufacturing methods and the production of tools on flakes. Hominin occupations correspond with humid periods, particularly Marine Isotope Stages 7 and 5 of the Late Pleistocene. The Middle Palaeolithic occupations were situated along the Jubbah palaeolake-shores, in a grassland setting with some trees. Populations procured different raw materials across the lake region to manufacture stone tools, using the implements to process plants and animals. To reach the Jubbah palaeolake, Middle Palaeolithic populations travelled into the ameliorated Nefud Desert interior, possibly gaining access from multiple directions, either using routes from the north and west (the Levant and the Sinai), the north (the Mesopotamian plains and the Euphrates basin), or the east (the Persian Gulf). The Jubbah stone tool assemblages have their own suite of technological characters, but have types reminiscent of both African Middle Stone Age and Levantine Middle Palaeolithic industries. Comparative inter-regional analysis of core technology indicates morphological similarities with the Levantine Tabun C assemblage, associated with human fossils controversially identified as either Neanderthals or Homo sapiens.

Pleistocene Climate Change in Arabia: Developing a Framework for Hominin Dispersal over the Last 350 ka

Environmental change in Arabia has oscillated between climatic extremes throughout the Quaternary period with evidence for ancient pluvials, apparent in the lacustrine sediments, alluvial fans and gravels, paleosols, and speleothems (e.g., McClure, 1976; Schultz and Whitney, 1986; Parker et al., 2006a, 2006b; Lezine et al., 2007; Fleitmann et al., 2007). Conversely, there are numerous signals that Arabia was also subjected to extremes in aridity, most obviously manifested in the expansive sand seas comprising the Nafud, Rub’ al Khali, and Wahiba deserts, as well as fracture calcites from hyperalkaline springs (Clark and Fontes, 1990) and petrogypsic soil horizons (Rose, 2006).

Beyond the Levant: first evidence of a pre-pottery Neolithic incursion into the Nefud Desert, Saudi Arabia

Pre-Pottery Neolithic assemblages are best known from the fertile areas of the Mediterranean Levant. The archaeological site of Jebel Qattar 101 (JQ-101), at Jubbah in the southern part of the Nefud Desert of northern Saudi Arabia, contains a large collection of stone tools, adjacent to an Early Holocene palaeolake. The stone tool assemblage contains lithic types, including El-Khiam and Helwan projectile points, which are similar to those recorded in Pre-Pottery Neolithic A and Pre-Pottery Neolithic B assemblages in the Fertile Crescent. Jebel Qattar lies ∼500 kilometres outside the previously identified geographic range of Pre-Pottery Neolithic cultures. Technological analysis of the typologically diagnostic Jebel Qattar 101 projectile points indicates a unique strategy to manufacture the final forms, thereby raising the possibility of either direct migration of Levantine groups or the acculturation of mobile communities in Arabia. The discovery of the Early Holocene site of Jebel Qattar suggests that our view of the geographic distribution and character of Pre-Pottery Neolithic cultures may be in need of revision.

Phytolith analysis from the archaeological site of Kush, Ras al-Khaimah, United Arab Emirates

Despite the wealth of archaeological sites and excellent conditions for preservation, few phytolith investigations have been undertaken from the Arabian Gulf region. The results from the Sasanian and Islamic archaeological tell of Kush, Ras al-Khaimah, United Arab Emirates, are presented. Kush is situated just inside the Gulf on an important trade route. The occupation sequence dates from the 4th century A.D. until the 13th century A.D., recording the development of the site in the Sasanian period, followed by the arrival of Islam in the 7th century A.D. and the final abandonment of the site in the late 13th century when the nearby site of al-Mataf (Julfar) began to develop closer to the present day coastline. All the samples analyzed contained abundant phytoliths (short cells, elongated cells, and groups of elongated cells) of various types. They included date palm (Phoenix dactylifera), papillae (possibly from barley (Hordeum)), and hair cells possibly from species of canary grass (Phalaris spp.). Some researchers have suggested that groups of elongated cells may indicate the presence of irrigation in semiarid environments. The present results for this class of phytoliths appeared to imply that intensive irrigation was unlikely to have taken place around Kush.

Alluvial fan records from southeast Arabia reveal multiple windows for human dispersal

The dispersal of human populations out of Africa into Arabia was most likely linked to episodes of climatic amelioration, when increased monsoon rainfall led to the activation of drainage systems, improved freshwater availability, and the development of regional vegetation. Here we present the first dated terrestrial record from southeast Arabia that provides evidence for increased rainfall and the expansion of vegetation during both glacial and interglacial periods. Findings from extensive alluvial fan deposits indicate that drainage system activation occurred during Marine Isotope Stage (MIS) 6 (ca. 160–150 ka), MIS 5 (ca. 130–75 ka), and during early MIS 3 (ca. 55 ka). The development of active freshwater systems during these periods corresponds with monsoon intensity increases during insolation maxima, suggesting that humid periods in Arabia were not confined to eccentricity-paced deglaciations, and providing paleoenvironmental support for multiple windows of opportunity for dispersal out of Africa during the late Pleistocene.

Human Burial Evidence from Hattab II Cave and the Question of Continuity in Late Pleistocene–Holocene Mortuary Practices in Northwest Africa

Archaeological excavations in 2002-3 at Hattab H Cave in northwestern Morocco revealed all undisturbed Late Palaeolithic Iberomaurusian human burial. This is the first Iberomaurusian inhumation discovered in the region. The skeleton is probably that Of a male aged between 25 and 30 years. The individual shows a characteristic absence of the central upper incisors reported in other Iberomaurusian burials. Accompanying the burial are a stone core and a number of grave goods including bone points, a marine gastropod and a gazelle horn core. Thermoluminescence dating of a burnt stone artefact in association with the burial has provided an age of 8900 +/- 1100 BP. This is one of the youngest ages reported for the Iberomaurusian and raises questions about persistence of hunter-gatherer societies in the Maghreb and the potential for continuity in burial practices with the earliest Neolithic.

Holocene development of multiple dune generations in the northeast Rub’ al-Khali, United Arab Emirates

It has been hypothesised that in sand seas where multiple dune generations occur, each generation represents a distinct terrestrial response to contrasting palaeoatmospheric circulation conditions (Lancaster N, Kocurek G, Singhvi A, Pandey V, Deynoux M, Ghienne J-F et al. (2002) Late Pleistocene and Holocene dune activity and wind regimes in the western Sahara Desert of Mauritania. Geology 30: 991–994). However, reconstructing dunefield accumulation and preservation chronologies has often utilised a limited suite of samples because of the difficulties realised in accessing unconsolidated aeolian sands, which has limited the capacity to test this hypothesis. In the eastern United Arab Emirates, artificial excavation for quarrying and construction have generated a unique opportunity to examine and sample the internal structures of dune systems, and to generate data to test the hypothesis of dune generational development. This paper presents new data and chronologies from a multigenerational analysis of dune accumulation in the northeast dunefield of the Rub’ al-Khali. A complex developmental history during the Holocene is revealed, which does not fully conform to the notion of each dune generation forming in distinct palaeoclimatic phases, since the age ranges represented in the accumulation of secondary dunes is also found within a longer suite of accumulation ages from the underlying megaridges.

The structural geomorphology of the Isle of Portland, southern England

The Isle of Portland, southern England, is composed of gently folded Upper Jurassic Beds ranging from the Kimmeridge Clay through the Portland Group to the Lower Purbeck Group which are gently folded to form part of the northern end of the Shambles Syncline. The essential arrangement of the beds is for hard, jointed well-bedded and permeable Purbeck and Portland limestones to overlie the Kimmeridge Clay members. The jointing along NW-SE, NE-SW, N-S and E-W master and conjugate sets closely parallels the axis of the syncline and the NNE-SSW fault pattern of the Purbeck Anticline and is a major regional landform control at all scales from the occurrence and form of individual rock falls to the shape of the island itself. Portland has a large number of landslips, which have been mapped from colour air photography. Their spatial pattern is spectacularly related to the geological conditions of the island and varies in size and type in a systematic manner as the thickness of clay and the orientation of the dip changes with respect to the coastline orientation. The slips, which occur predominantly in the winter months after heavy rainfall, are of frequent occurrence and pose major hazards to engineering structures. The landslide pattern and the overall morphology of the island is used to suggest a tentative model of landscape evolution which emphasizes the process of lateral spreading, loading, clay extrusion and erosional unloading.