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The first three papers in the Loess and Bee-eaters series sought to establish links between the nesting of bee-eater birds (family Meropidae) and the occurrence of loess deposits. For the European bee-eater there is a close and fairly obvious relationship; for the Carmine bee-eater nesting in the 15 N band of Africa more assumptions and adjustments have to be made, and for the Blue-cheeked bee-eater nesting in the Indus region the relationship is becoming vague and more speculative. The trend continues with the Australian bee-eater- the rainbowbird ( Merops ornatus ). We lack precise maps of loess distribution in Australia and there is an equal lack of detailed and accurate maps of the distribution of rainbowbird nesting. Loess in Australia is elusive; the maps of Kriger and Scheidig show little detail and are essentially contradictory. If the deterministic theory of loess deposit formation were applied, it would suggest that loess should be found in the region where Pleistocene cold-phase mountain glaciers occurred. In the last glacial phase there was very little glacial occurrence in Australia; probably a limited region near Mount Kosciuszko. This places some glacial activity in the extreme southeast of the country. This agrees, more or less, with the data on the Kriger map. Fry has mapped the breeding zones of the rainbowbird and they are concentrated in the southeast and southwest. The maps are not precise but there does seem to be indications of co-existence of bee-eater nests and loessic regions. This is not the clearcut relationship which has been observed with the European bee-eater but it is suggestive. The ill-defined loess/dust regions and the poorly demarcated nesting zones of the rainbowbird do seem to be coincident. Better mapping is urgently required for loess in Australia, and nesting zones of M. ornatus . It may be that dust rather than loess is the ground material to be observed in Australia. There are still problems of integrating the dust and loess concepts, but mapping of dust deposits does produce some coincidence with rainbowbird nesting. The region of Vertisol occurrence appears to be a barrier to the spread of rainbowbird nesting. [ABSTRACT FROM AUTHOR]

Part 3 of the study of loess ground and bee-eater birds concerns birds and ground in the north-western part of the Indian Sub-continent. Three species of bee-eaters are considered, relative to the Indus region: the Green bee-eater, the Blue-cheeked bee-eater and the European bee-eater. Loess in the Indus region is considered via the deterministic approach to loess deposit formation; the P events occur in the mountains of the western part of High Asia, particles are formed by the action of mountain glaciers. Major T actions involve the five rivers of the region which carry loess material into the Punjab plains. Subsequent T actions deliver loess material to local deposits, which provide nesting grounds for bee-eaters. To some extent the bee-eaters define the loess. The Green bee-eater is small (16–18 cm long) and lives over all of India and Pakistan-nesting ground is available everywhere. The larger bee-eaters (European and Blue-cheeked: (25 cm)) are more constrained by ground properties-they require the ideal properties of loess ground (an ideal positioning relative to the Heneberg compromise) for nesting, and thus tend to define loess extent. Soil mechanics requires that more exact stress conditions are achieved when a relatively large nest tunnel is being constructed. [ABSTRACT FROM AUTHOR]

The Northern Carmine Bee-Eater (Merops nubicus) lives and breeds in a well demarcated region stretching across Africa close to the 15°N line of latitude. The Bee-Eater zone appears to be associated with a band of loess, defined by Scheidig on his 1934 map as second-order loess. Bee-eaters are known to favour loess for nesting tunnels and it appears that the 15°N material is sufficiently loess-like. Obvious sources for particulate materials for the 15°N band are the Fonta-Djalon highlands which supply sedimentary material to the River Niger; the Bodele Depression, the deepest part of Lake Megachad, source of dust for the World; the Ethiopian highlands at the eastern end of 15°N which supply silt to the Nile system and particulates to the 15°N region. In soil moisture terms the region is ustic, which is possibly a necessary condition for bee-eater nests. The clastic material requires an ustic environment. The River Niger can be seen as a loess river; in some senses a mirror-image of a major loess river like the Danube; but where a restricted range of particle inputs leads to a restricted range of loess deposit outputs. Nevertheless loess river considerations can be applied. The Niger delivers second-order loess and an important loessic admixture to the landscape. Enough loess for selective nesters like the Carmine Bee-Eaters to build their nest tunnels in it. It seems likely that climate change will cause a change in bee-eater distribution; it seems unlikely that they will abandon their nesting regions, the living and wintering zones may shift. [ABSTRACT FROM AUTHOR]

Abstract: A stratigraphically and temporally ordered sequence of channel calcretes preserved along the Wadi Dana, Southern Jordan, records the Quaternary evolution of the formation and infilling of rock-cut channels and their subsequent incision in a tectonically subsiding basin. It is currently unknown under what palaeoenvironmental conditions these non-pedogenic calcretes formed. Stable isotope analyses have been used to investigate whether any past topographical, hydrological, vegetational, diagenetic, and/or temporal signatures can be identified from the channel calcretes. The results of this research indicate that channel calcrete development is influenced by altitudinal variation (affecting vegetation and hydrology) within the landscape as well as location within individual wadi channels (which has an affect on diagenetic processes). The lack of calcretisation of a terrace that is between +1 and 1.5m above the modern wadi floor supports the idea that the environment is currently too arid for calcrete to develop. Thus the presence of older Wadi Dana channel duricrusts suggests wetter conditions when they formed. The δ 18O data of the calcrete implies cooler conditions than today, as there is little evidence of a strong evaporative effect. Any temporal control is limited and mainly a function of stratigraphic position with some numeric dating. [Copyright &y& Elsevier]

Calcretes that form in non-pedogenic settings have been widely reported in the geomorphological and geological literature, yet they are still poorly understood in comparison with pedogenic varieties. This may be because there are assorted types of non-pedogenic calcretes (often loosely referred to as groundwater calcretes, but encompassing groundwater, phreatic, open valley or confined channel calcrete types) forming within vadose and phreatic environments in different geomorphological settings. Relatively few studies have described the detailed petrological characteristics of such calcretes, leading Wright and Tucker (Calcretes; International Association of Sedimentologists Reprint Series, (1991) Vol. 2, Blackwell Scientific Publications, Oxford, p. 10) to suggest that “much more work is needed to define the ‘groundwater calcrete facies’ and to devise criteria for its recognition” so that the various non-pedogenic calcretes can be identified within the Quaternary as well as further back in the geological record. Most descriptions of groundwater calcretes are highly generalistic and do not take into account the variability that may occur as a result of calcretes forming in different positions within a landscape and affected by separate controls. Thus, the range of groundwater calcretes that exists now needs to be studied individually to identify patterns within the distinct types.As a step towards expanding our knowledge of the variety of non-pedogenic calcretes, this paper describes the petrology, micromorphology, and mode of development of one of these types of calcrete, namely that which forms within valley locations (but not in definite fluvial channels). Late Quaternary to Holocene valley calcretes are described from various dry valleys (mekgacha) across the Kalahari region of central Botswana, with the majority of samples collected from trunk and tributary valleys of the Okwa. Samples have been analysed in thin section and under scanning electron microscope in order to determine the carbonate matrix type and calcrete micromorphology. In general, most samples consist of grains of quartzose Kalahari sand cemented by fine crystalline, often glaebular, grain-coating and pore-filling micrite. Cement types are fairly consistent and not as micromorphologically variable as has been noted for other Kalahari calcretes. Biological inputs are prevalent in many samples and include networks of calcified rootlets. These characteristics reflect the fact that the calcretes formed in a relatively near-surface environment with relatively high rates of evaporation. [Copyright &y& Elsevier]

Investigates the role of sea spray in the diagenetic alteration, cementation and weathering of late Pleistocene aeoloanites in the vadose zone from Bermuda. Increase in secondary porosity; Processes operating in the sea spray zone.

The Messinian lagoonal carbonate–evaporite sequence of Cyrenaica, north‐east Libya, hosts: (i) opaline nodules in gypsiferous microbial‐rich mudstone; (ii) nodules replacing poikilotopic gypsum cementing bioclastic carbonates; and (iii) bedded porcelanite with large lenticular gypsum pseudomorphs intercalated with recrystallized microbial mats. Optical microscopy, scanning electron microscopy, backscattered electron images – secondary electron images, X‐ray fluorescence, X‐ray diffraction and cathodoluminescence techniques were employed to elucidate on the early stages of chert diagenesis and demonstrate the role of moganite in the formation of varieties of chalcedony during silicification. The opaline nodules composed of opal‐A, exhibit shrinkage cracks lined by isopachous fibrous quartzine underlain by a thin birefringent zone. This suggests that quartzine may develop by crystallization and conversion of opal‐A through a transitional moganite. The quartzine is followed by amorphous silica gel that converts into length‐fast chalcedony. By contrast, lutecite evolved by silica replacement of gypsum through a transitional moganite phase, which forms an amorphous zone in apparent optical continuity with the fibrous lutecite; as moganite advances by pseudo‐crystalline terminations controlled by the gypsum cleavage. In gypsified oyster shells, intercrystalline organic matter enveloping pseudomorphed shell microstructures enabled moganite nucleation that merges syntaxially around the gypsum crystal rim. The associated lutecite occurs as radial‐fibrous beekite aggregates that are consistent with early shell silicification. The bedded porcelanite consists of opal‐CT groundmass undergoing recrystallization and enclosing micro‐cavities lined by quartzine. The associated pseudomorphs display phases of gypsum replacement by moganite and lutecite at the outer margin, followed by dissolution and cavity filling by quartz varieties in response to fluid flushing. In all cases, organic matter and microbes played a vital role in the silicification process. [ABSTRACT FROM AUTHOR]

This paper reports the initial findings from a study of soil moisture within a series of three unlithified dune ridges at Studland, Dorset, on the southern coast of England. The infiltration and movement ofmoisture was monitored at each dune crest, slack and mid position onwindward and leeward flanks, using capacitance probe technology. Themean moisture level in the dunes (excluding the troughs) was close to 7% and ranged between 1 and 18%. The rapidity and sensitivity of response of the dune sands to wetting and draining decreased markedly with depth over a distance of 1.3 m, and the behaviour patterns fell into three clear zones: 0-45 cm; 60-90 cm 110-150 cm. The uppermost was the most sensitive and experienced the greatest number of wetting and drying cycles. Differences in moisture regime also varied according to the density of vegetation cover and position over the dune. On well vegetated sands the moisture was concentrated in the upper levelsof the dune, corresponding to the thin soil and the rhizosphere, andin unvegetated dunes moisture was retained at depth. Spatially, crests are the driest positions and small but persistent differences in moisture were recorded between windward and leeward flanks which may reflect the movement of subsurface moisture along bedding planes. These observed patterns correspond well with existing knowledge of susceptibility to early diagenetic change within the vadose zone of dune sands. [ABSTRACT FROM AUTHOR]

Abstract: The European bee-eater (Merops apiaster L.1758) nests in tunnels in loess deposits. The properties of loess make it particularly suitable for tunnel nesting birds (a major factor is the metastable nature of the ground). The ‘Heneberg Compromise’ operates whereby the conflicting requirements of tunnel stability and ease of excavation dictate the optimum particle size for usable ground. The open structure of loess deposits, due to particle shape and airfall sedimentation, allows gas movement in nesting tunnels. It also allows local compaction during nest building which strengthens tunnel walls. The short range nature of the interparticle bonds in the ground material provides an almost ideal construction environment, ensuring a low plasticity index, which appears to be critical for tunnel building birds. Bee-eaters and sand martins dig tunnels in loess as ‘primary nesters’. These loess tunnels are used by many ‘secondary nesters’. The bee-eater is an efficient ecosystem engineer. Distribution maps of European bee-eater nesting, and of loess deposits, show some coincidence. A concentration of loess and nest regions is observed to the north of the Black Sea where the rivers Dnepr and Don deliver loess material, and to the west of the Black Sea in the Danube basin. The birds nest to the north of the demarcated Meigs arid/semi-arid zones in Africa, but spend winters to the south of these regions. They fly long distances from wintering zones to loess nesting regions, the longest migration of the bee-eaters. Even relatively minor loess deposits on the fringes of the breeding range, as in southern Poland, have their bee-eater inhabitants. [Copyright &y& Elsevier]

Image merging has gained acceptance in geological remote sensing, however it has rarely been applied in geomorphology. We report on the usefulness of principal components substitution (PCS) to merge IRS panchromatic data with multispectral Thematic Mapper (TM) imagery, to map commonly encountered desert geomorphological features, and in relative age dating of alluvial surfaces. The merged data were applied to the identification and mapping of geomorphological features along two geolo-gically different mountain fronts in central Saudi Arabia. Two types of geomorphological maps have been created. A morphogenetic map that distinguishes between aeolian landforms, fluvial landforms, desert pavements, and gypsum crusts. Second, a morphochronological map, which shows the relative age of four geomorphic surfaces developed on an alluvial fan. The construction of the two maps is supported by field observations and laboratory measurements. Using the optimum index factor (OIF), a TM band 1, 5 and 7 image (of 20 merged composites) was found to be the optimum colour composite image for the geomorphological features in this arid environment. We discuss our findings in the context of the spatial and spectral properties required for applied geomorphological remote sensing. [ABSTRACT FROM AUTHOR]

Abstract In desert dune environments, vegetation may be an indicator of dune stability and rates of sediment transport. As topography and underlying controls of vegetation vary over large spatial areas, variations in dune form make scaling up of field research difficult. To mitigate this, and to identify spatial variations in vegetation distributions in a Saudi Arabian sand sea, spectral information from high resolution satellite images was classified to map polygons of shrub vegetation over 360 km2 of well-defined linear dunes, broken linear dunes and dome dune forms. When compared to topographic characteristics of the landscape, extracted from a digital elevation model, vegetation densities were often highest on 10–20° slopes elevated above interdune salt deposits on dune flanks. Spatially this was confined to small areas, and density was not always related to dune form, more to access of groundwater which encouraged colonisation on the tops of some dunes. Field observations identified shrubs of mainly Calligonum genus whose size is related to the amounts of salts, moving sediment, and access to the water table that varies within and between dune forms. Shrub density is likened to surface roughness (z 0) to better understand sediment movement and modelling in dunes. Highlights • High res. satellite images detect shrubs across linear, dome dunes and interdunes. • Greatest densities of shrub vegetation are found on 10–20-degree slopes. • Shrubs that colonise tops of dunes indicate groundwater is present and accessible. • Character of interdune shrubs are affected by evaporite salts and wind intensity. • Mapping density, or surface roughness, can be helpful for modelling. [ABSTRACT FROM AUTHOR]

Aim: The Animal Fun program, a universal early intervention program that aims to promote the motor skills and social-emotional development of young children, has shown to improve overall motor proficiency and social and behavioural outcomes. The aim of the current study was to evaluate the program's impact on children's aiming and catching, and balance skills.Methods: A cluster randomised control trial was employed, with six intervention and six control (following normal curriculum) schools. A total sample of 511 children (257 boys and 254 girls), aged 4-6 years presented at pre-test. Children were tested across three time points, pre-test, post intervention (six months later) and follow-up (18 months after pre-test), using the Movement Assessment Battery for Children-2 Aiming and Catching, and Balance tasks. The study also tested for potential moderators including pre-test motor proficiency, age, gender, and cognitive performance.Results: Participation in Animal Fun improved children's one leg balance at post-test and follow-up compared to control children, regardless of pre-test motor proficiency, age, gender, or pre-test cognitive performance. Participation in Animal Fun also improved throwing skills for those children with poorer motor proficiency compared to the controls with poorer motor performance. Interestingly, it was found that the control group's catching skills improved more than the intervention group at follow up.Conclusions: The study provides some promising results regarding the efficacy of the Animal Fun program in improving one-leg balance for all children, and throwing skills for those children with poorer motor proficiency, while also suggesting potential confounding factors, such as maturational issues and other individual factors (e.g., a child's participation in extracurricular activity). [ABSTRACT FROM AUTHOR]

Archaeological sites in northern Africa provide a rich record of increasing importance for the origins of modern human behaviour and for understanding human dispersal out of Africa. However, the timing and nature of Palaeolithic human behaviour and dispersal across north-western Africa (the Maghreb), and their relationship to local environmental conditions, remain poorly understood. The cave of Rhafas (northeast Morocco) provides valuable chronological information about cultural changes in the Maghreb during the Palaeolithic due to its long stratified archaeological sequence comprising Middle Stone Age (MSA), Later Stone Age (LSA) and Neolithic occupation layers. In this study, we apply optically stimulated luminescence (OSL) dating on sand-sized quartz grains to the cave deposits of Rhafas, as well as to a recently excavated section on the terrace in front of the cave entrance. We hereby provide a revised chronostratigraphy for the archaeological sequence at the site. We combine these results with geological and sedimentological multi-proxy investigations to gain insights into site formation processes and the palaeoenvironmental record of the region. The older sedimentological units at Rhafas were deposited between 135 ka and 57 ka (MIS 6 –MIS 3) and are associated with the MSA technocomplex. Tanged pieces start to occur in the archaeological layers around 109 ka, which is consistent with previously published chronological data from the Maghreb. A well indurated duricrust indicates favourable climatic conditions for the pedogenic cementation by carbonates of sediment layers at the site after 57 ka. Overlying deposits attributed to the LSA technocomplex yield ages of ~21 ka and ~15 ka, corresponding to the last glacial period, and fall well within the previously established occupation phase in the Maghreb. The last occupation phase at Rhafas took place during the Neolithic and is dated to ~7.8 ka. [ABSTRACT FROM AUTHOR]

Animal Fun was designed to enhance motor and social development in young children. Its efficacy in improving motor skills was presented previously using a randomised controlled trial and a multivariate nested cohort design. Based on the Environmental Stress Hypothesis, it was argued that the program would also result in positive mental health outcomes, investigated in the current study. Pre-intervention scores were recorded for 511 children aged 4.83-6.17 years (M=5.42, SD=.30). Intervention and control groups were compared 6 months following intervention, and again in their first school year. Changes in teacher-rated prosocial behaviour and total difficulties were assessed using the Strengths and Difficulties Questionnaire, and data analysed using Generalised Linear Mixed Models. There was a significant improvement in prosocial behaviour of children in the intervention group six months after initial testing, which remained at 18-month follow-up. Total difficulties decreased at 6 months for the intervention group, with no change at 18 months. This effect was present only for the hyperactivity/inattention subscale. The only significant change for the control group was an increase in hyperactivity/inattention scores from pre-intervention to 18-month follow-up. The Animal Fun program appears to be effective in improving social and behavioural outcomes. [ABSTRACT FROM AUTHOR]

Abstract: A Quaternary site at Drmno (comprising of Middle and Late Pleistocene loess–palaeosol sequences) near Kostolac, northeast Serbia, attracted attention from the general public and scientists, when several steppe mammoth and other mammal skeletons from Middle Pleistocene fluvial deposits were discovered in 2009 and 2012. This paper presents the combination of malacological and enviromagnetic analyses, preliminary luminescence dating, litho-pedostratigraphic and palaeo-relief investigations that were applied to the Nosak loess–palaeosol sequence for the 2012 findings. The results confirm and emphasize the antiquity of the sediments preserved in the Nosak section and demonstrate the significance of the detailed and relatively complete palaeoenvironmental record they contain. These discoveries can significantly contribute to setting the background towards an improved understanding of the evolution of mammoths on the European continent. [Copyright &y& Elsevier]

Abstract: Barrier systems contain lengthy, but complex, records of long-term environmental fluctuations. The Wilderness embayment, South Africa, contains a system of shore-parallel barriers reaching up to 200m above modern sea level. This study reports the results of chronological, topographical (both on- and off-shore), sedimentological and micromorphological analyses within the Wilderness embayment. Sixty-one new luminescence ages from sixteen sites in unconsolidated dunes and three separate barriers are presented which, when combined with previously published luminescence ages from the area, provide a high-resolution chronological framework for the emplacement and evolution of the barrier system. The preserved barriers have been constructed within at least the last two glacial–interglacial cycles with notable phases between 241–221ka, 159–143ka, 130–120ka, 92–87ka and post 6ka. Multiple phases of barrier construction occurred during sea-level highstands, with sediment deposition on each individual barrier occurring over at least two interglacials. Holocene evolution of the system sheds light on earlier events, with dune preservation occurring only during early regression from the Mid-Holocene highstand. Tectonic stability at Wilderness allowed glacio-eustatically formed shorelines to occupy similar positions on multiple occasions. This, in conjunction with a relatively humid climate and a well-vegetated landscape, enabled deflated sediment from beaches to form dunes which stacked upon each other to form an extensive and complex vertical accretionary sequence. Repeated erosion and recycling of pre-existing barriers as well as barrier construction on what is currently the off-shore platform during still-stands in sea-level regressional cycles, when sea levels dropped below ca −50m from the present day, has added to the complexity of the preserved terrestrial barrier record. The Wilderness barrier system contrasts with barriers developed elsewhere in the world where higher rates of crustal uplift have allowed preservation of a more complete and more widely spaced palaeorecord. This research also shows the utility of integrating off-shore topography as revealed by bathymetry, with terrestrial topographic data for the better understanding of the evolution of palaeo-coastlines and the preserved dune record found on present-day coastal plains. Local variation in the topography of the continental shelf at Wilderness has generated spatial and temporal complexity within the sedimentary records of individual barriers as well as having a significant influence on preservation. [Copyright &y& Elsevier]

Abstract: Recent research in Europe, Africa, and Southeast Asia suggests that we can no longer assume a direct and exclusive link between anatomically modern humans and behavioral modernity (the ‘human revolution’), and assume that the presence of either one implies the presence of the other: discussions of the emergence of cultural complexity have to proceed with greater scrutiny of the evidence on a site-by-site basis to establish secure associations between the archaeology present there and the hominins who created it. This paper presents one such case study: Niah Cave in Sarawak on the island of Borneo, famous for the discovery in 1958 in the West Mouth of the Great Cave of a modern human skull, the ‘Deep Skull,’ controversially associated with radiocarbon dates of ca. 40,000 years before the present. A new chronostratigraphy has been developed through a re-investigation of the lithostratigraphy left by the earlier excavations, AMS-dating using three different comparative pre-treatments including ABOX of charcoal, and U-series using the Diffusion-Absorption model applied to fragments of bones from the Deep Skull itself. Stratigraphic reasons for earlier uncertainties about the antiquity of the skull are examined, and it is shown not to be an ‘intrusive’ artifact. It was probably excavated from fluvial-pond-desiccation deposits that accumulated episodically in a shallow basin immediately behind the cave entrance lip, in a climate that ranged from times of comparative aridity with complete desiccation, to episodes of greater surface wetness, changes attributed to regional climatic fluctuations. Vegetation outside the cave varied significantly over time, including wet lowland forest, montane forest, savannah, and grassland. The new dates and the lithostratigraphy relate the Deep Skull to evidence of episodes of human activity that range in date from ca. 46,000 to ca. 34,000 years ago. Initial investigations of sediment scorching, pollen, palynomorphs, phytoliths, plant macrofossils, and starch grains recovered from existing exposures, and of vertebrates from the current and the earlier excavations, suggest that human foraging during these times was marked by habitat-tailored hunting technologies, the collection and processing of toxic plants for consumption, and, perhaps, the use of fire at some forest-edges. The Niah evidence demonstrates the sophisticated nature of the subsistence behavior developed by modern humans to exploit the tropical environments that they encountered in Southeast Asia, including rainforest. [Copyright &y& Elsevier]

This article focuses on matters related to past human activity and geomorphological change in a Guano-Rich Tropical Cave Mouth. The Great Cave at Niah is huge and complex. It is developed in the Subis Limestone of Sarawak in northern Borneo. Although the first excavations of the Great Cave were already noted, it only became widely known from the excavations in the West Mouth by archeologists Tom and Barbara Harrisson in the 1950s and 1960s. The deposits yielded the "Deep Skull"--remains of an anatomically modern human associated with radiocarbon dates of ca. 40,000 B.P. from associated charcoal suspected a later Pleistocene age, while the integrity and interpretation of these caves were questioned.

The sediments and landforms at the Tsodilo Hills, in the northwestern Kalahari desert, provide an opportunity to directly investigate the late Quaternary wetting and drying of the region from evidence at a single site. Lacustrine carbonates, including incorporated molluscs and diatoms, a lake shoreline feature and stabalised linear dunes were investigated for their constituent palaeoenvironmental signals. Chronometric control is provided by calibrated 14C, AMS and OSL dating. The evidence suggests that linear dune construction has not occurred since the Last Glacial Maximum, with particular development from 36 to 28 ka. Lake stands indicating wetter regional conditions than present occurred at 40–32 ka, with more seasonal conditions from 36 ka, and at 27–12 ka with a possible drying out at 22–19 ka. Data are consistent with other independent studies from the region, and with recent evidence obtained from Atlantic cores off the coast of Namibia. It is concluded that careful consideration of multi-proxy data from a single location can assist in resolving discrepancies that arise from independent studies of lake, cave and dune records in the Kalahari. [Copyright &y& Elsevier]