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Lake sediment archives covering several glacial cycles are scarce in the Southern Hemisphere and they are challenging to date. Here we present the chronostratigraphy of the oldest continuous lake sediment archive in Tasmania, Australia; a 5.5 m and 270 ka (Marine Isotope Stage 8) sediment core from Lake Selina. We employ radiometric dating (radiocarbon and optically stimulated luminescence) and relative dating (geomagnetic and climate comparisons). Bayesian modeling of the radiometric ages reaches back to 80 ka (1.7 m) and relative dating using a dynamic programing algorithm allows dating of the full sequence. Elemental data, magnetic properties and beryllium isotopes from Lake Selina reveal a close fit to Antarctic ice core climate proxies. Weaker correlation during the Last Glacial Period (MIS 2–4) is attributed to additional local factors impacting Lake Selina proxies at a time of climate changes and human arrival into Tasmania. Over that period, full vector paleomagnetic records and authigenic 10Be/9Be ratios are combined to identify the Laschamp geomagnetic excursion for the first time in Australia and constrain the chronology. The multi-method approach provides two preferred age models, indiscernible within their uncertainties, which allows the use of a geomagnetic dipole-independent (full archive) or a climate-independent (111 ka to present) age model. • Chronostratigraphy of a 266 ± 8 ka continuous lake sediment archive from Australia. • We combine radiometric (14C, OSL) and relative dating (geomagnetic and climatic). • Bayesian modeling and dynamic programing integrate dating constraints. • First identification of the Laschamp geomagnetic excursion in Australia. [ABSTRACT FROM AUTHOR]

The Homa Peninsula, in southwestern Kenya, continues to yield insights into Oldowan hominin landscape behaviors. The Late Pliocene locality of Nyayanga (∼3–2.6 Ma) preserves some of the oldest Oldowan tools. At the Early Pleistocene locality of Kanjera South (∼2 Ma) toolmakers procured a diversity of raw materials from over 10 km away and strategically reduced them in a grassland-dominated ecosystem. Here, we report findings from Sare-Abururu, a younger (∼1.7 Ma) Oldowan locality approximately 12 km southeast of Kanjera South and 18 km east of Nyayanga. Sare-Abururu has yielded 1754 artifacts in relatively undisturbed low-energy silts and sands. Stable isotopic analysis of pedogenic carbonates suggests that hominin activities were carried out in a grassland-dominated setting with similar vegetation structure as documented at Kanjera South. The composition of a nearby paleo-conglomerate indicates that high-quality stone raw materials were locally abundant. Toolmakers at Sare-Abururu produced angular fragments from quartz pebbles, representing a considerable contrast to the strategies used to reduce high quality raw materials at Kanjera South. Although lithic reduction at Sare-Abururu was technologically simple, toolmakers proficiently produced cutting edges, made few mistakes and exhibited a mastery of platform management, demonstrating that expedient technical strategies do not necessarily indicate a lack of skill or suitable raw materials. Lithic procurement and reduction patterns on the Homa Peninsula appear to reflect variation in local resource contexts rather than large-scale evolutionary changes in mobility, energy budget, or toolmaker cognition. [ABSTRACT FROM AUTHOR]

Abstract: The current understanding of landscape scale variation in mid-Pleistocene hominin behavior is limited. Most of our understanding derives from a few localities in eastern Africa. Consequently, we know very little about hominin landscape use outside this region, despite the fact that mid-Pleistocene hominins occupied other climatic zones including temperate, and mid-latitude ecosystems. The winter rainfall zone in South Africa represents one of the world's most diverse ecosystems. Although mammal diversity is relatively low in these habitats this is compensated by the tremendous floral diversity. Buried Pleistocene land surfaces in the region provide an opportunity to understand how humans adapted to this unique, mid-latitude environment prior to the Last Interglacial. The dunefield locality of Elandsfontein in the Western Cape of South Africa is one of the richest known paleontological and archeological sites in southern Africa. It records details of landscape formation history, enabling detailed reconstruction of the ancient environments in this winter rainfall-dominated region. This dunefield archive allows us to posit the taphonomic history of newly excavated archaeological material and previously collected specimens. Here we provide initial results from the excavation and geological analysis of the Elandsfontein dunefield and provide new insights into the formation history of the archaeological and paleontological deposits. This includes indications of multiple pedogenic intervals and groundwater table fluctuations. The combination of geological, paleontological and archaeological data provides a framework for evaluating how hominins interacted with the unique ecosystems of the Cape Floral Region of South Africa during the mid-Pleistocene. [Copyright &y& Elsevier]

Given the steep present-day climatic gradients in southern South Africa, comparative studies of its coastal and inland paleoclimate provide important insight into the region's spatial climate dynamics. We present a comparative study of new speleothem stable oxygen (δ18O) and carbon (δ13C) isotopic composition from Efflux Cave (EC; 113–19 ka, hiatus between 105 and 94 ka) in the Little Karoo inland basin and Herolds Bay Cave (HBC; 93–62 ka) at the boundary between the Cape coastal lowlands and the Palaeo-Agulhas Plain. Gaussian kernel based cross-correlation analyses against palaeoclimate proxy records show that rainfall seasonality at EC is related to rainfall amount in the South African interior, whereas HBC is similar to the South African east coast. Our new proxy records, corroborated by archaeological evidence from the Cape coastal lowlands and the Little Karoo, suggest that in both regions, surface water was readily available and grassland ecosystems with variable amounts of C 4 and C 3 grasses as well as fynbos communities could be found nearby. Cross-correlation analyses of the new records from EC and HBC compared to previously published speleothem records from southern South Africa show only limited statistical correlation. However, there are some similarities in overall trends of palaeoclimate change in the Cape coastal lowlands and the Little Karoo whereby Marine Isotope Stage (MIS) 5b (mainly Greenland Interstadial 22) and 4 generally have more summer rainfall and higher abundances of C 4 vegetation than MIS 5a and MIS 3. • The Little Karoo shows a close relation with the southern African interior. • The Cape coastal lowlands are connected with the east coast and Agulhas Current. • Southern South African speleothems show a consistent overall signal. • Summer rain and C 4 grasses are higher in MIS 5b and MIS 4 than MIS 5a and MIS 3. • Hunter-gatherers had access to water, grassland faunas and fynbos biome in MIS 5-3. [ABSTRACT FROM AUTHOR]