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Terrestrial and lacustrine Neogene and Quaternary sediments in the Libyan Fezzan provide key evidence for paleoclimate changes in the central Sahara, associated with Lake Megafezzan. Understanding of Holocene and late Pleistocene deposits is resolved, but the age of older sediments is not. We provide the first high-resolution chronology and stratigraphy of the Neogene deposits in the Fezzan Basin, and so also the central Sahara. The sediments are divided into three unconformity-bounded units, the oldest unit, comprising the Shabirinah and Brak formations, is dated using magnetostratigraphy. The Shabirinah Formation is a succession of lacustrine and fluvial units, locally with humid and arid paleosols, which progressively show evidence of increasing aridity up through the succession. The overlying Brak Formation is a pedogenically modified palustrine limestone at basin margin locations. All these units are dated to the early Aquitanian to late Serravallian in the early to mid-Miocene, having formed prior to major volcanic fields to the east. During the mid-late Aquitanian widespread stromatolitic lake sediments developed in SE Fezzan. In the late Burdigalian palustrine carbonate units developed that typically pass laterally into mixed clastic-paleosol-carbonate units that characterise basin margin situations. The Serravallian-aged Brak Formation is a highstand deposit developed during maximum lake extent, which formed due to restriction of basin drainage to the north and east, due to growth of the Jabal as Sawda volcanic centre and uplift of the SW shoulder of the Sirte Basin. Gradual aridification of the central Sahara occurred from the early Miocene, but this trend was periodically interrupted by humid phases during which Lake Megafezzan developed. The hyperaridity of the central Sahara must have developed after 11 Ma and the main drainage networks from the Fezzan Basin were established before 23 Ma, in the Oligocene indicating the great antiquity of major central Saharan river basins. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

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]

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]