Introduction: Calcium, Aluminum-rich inclusions (CAIs) are composed of the suite of minerals predicted to be the first to condense from a cooling gas of solar composition [1]. Yet, the first phase to condense, corundum, is rare in CAIs, having mostly reacted to form hibonite followed by other phases at lower temperatures. Many CAIs show evidence of complex postformational histories, including condensation, evaporation, and melting [e.g. 2, 3]. However, the nature of these thermal events and the nebular environments in which they took place are poorly constrained. Some corundum and corundum-hibonite grains appear to have survived or avoided these complex CAI reprocessing events. Such ultrarefractory CAIs may provide a clearer record of the O isotopic composition of the Sun and the evolution of the O isotopic composition of the planet-forming region [4][5][6].Here we present in situ O and Mg isotopic analyses of two corundum/hibonite inclusions that record differing formation histories.Methods: A thin section of ALH77307, a highly unequilibrated CO3.0 chondrite, was mapped for Ca, Al-rich, and Si-poor phases with a JEOL 7600F fieldemission scanning electron microscope. Energydispersive X-ray (EDX) maps were obtained at 1.5µm per pixel resolution. Identified corundum-bearing CAIs were subsequently analyzed using a Cameca SX100 electron microprobe to confirm their mineralogy and provide quantitative element compositions (by wavelength-dispersive X-ray spectrometry), including accurate Al/Mg ratios relevant to the associated Mg isotope analyses.Selected CAIs were subjected to O isotopic imaging with the JSC NanoSIMS 50L ion microprobe. Isotopic images of 16,17,18 O,

Organic synthesis on Mars occurs by the electrochemical reduction of CO2, a reaction that is highly relevant for abiotic organic synthesis on early Earth.

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We are increasingly aware of the role of emotions and emotional construction in social relationships. However, despite their significance, there are few constructs or theoretical approaches to the evolution of emotions that can be related to the prehistoric archaeological record. Whilst we frequently discuss how archaic humans might have thought, how they felt might seem to be beyond the realm of academic inquiry. In this paper we aim to open up the debate into the construction of emotion in early prehistory and propose key stages in the emotional motivation to help others, the feeling of compassion, in human evolution. We highlight what appear to be particularly significant thresholds for human social relationships and the evolution of the human mind.