The conceptual ability to source, combine, and store substances that enhance technology or social practices represents a benchmark in the evolution of complex human cognition. Excavations in 2008 at Blombos Cave, South Africa, revealed a processing workshop where a liquefied ochre-rich mixture was produced and stored in two Haliotis midae (abalone) shells 100,000 years ago. Ochre, bone, charcoal, grindstones, and hammerstones form a composite part of this production toolkit. The application of the mixture is unknown, but possibilities include decoration and skin protection.

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The speleothem delta function (SDF) provides a new transfer function between the ␦ 18 O signal of speleothem calcite and surface ground temperature. The function is based on physical principles, relating ␦ 18 O of the calcite to thermodynamic fractionation, and to the dripwater function, which in turn relates ␦ 18 O of dripwaters to that of the local precipitation and thus to the modification of source water in relationship to the geographical position of the site. The SDF must be calibrated against at least two reliable and well-dated palaeotemperature points. The end product is a reconstruction of absolute cave and surface temperatures. The technique is tested using a Holocene speleothem from north Norway, SG93, dated by 12 TIMS U-Th dates. The reconstructed temperature curve is presented and compared with the GISP2 ice-core record and with the historic record. In both cases the correlation with SG93 is impressive, indicating the validity of the technique.

Glacial erosion dramatically alters mountain landscapes, but the pace at which glaciers carve a previously fl uvial landscape remains poorly defi ned because long-term valley incision rates are diffi cult to measure. Here we reconstruct the lowering history of the Aare Valley, Switzerland, over the past 4 m.y. by dating cave sediments with cosmogenic 26 Al and 10 Be. Incision accelerated from ~120 m/m.y. to ~1200 m/m.y. at 0.8-1.0 Ma, at least 1 m.y. after the onset of local glaciation. Rapid incision may have been triggered by lowering of the equilibrium line altitude at the mid-Pleistocene climate transition.