Sequestration of Martian CO2 by mineral carbonation

Carbonation is the water-mediated replacement of silicate minerals, such as olivine, by carbonate, and is commonplace in the Earth’s crust. This reaction can remove significant quantities of CO2 from the atmosphere and store it over geological timescales. Here we present the first direct evidence for CO2 sequestration and storage on Mars by mineral carbonation. Electron beam imaging and analysis show that olivine and a plagioclase feldspar-rich mesostasis in the Lafayette meteorite have been replaced by carbonate. The susceptibility of olivine to replacement was enhanced by the presence of smectite veins along which CO2-rich fluids gained access to grain interiors. Lafayette was partially carbonated during the Amazonian, when liquid water was available intermittently and atmospheric CO2 concentrations were close to their present-day values. Earlier in Mars’ history, when the planet had a much thicker atmosphere and an active hydrosphere, carbonation is likely to have been an effective mechanism for sequestration of CO2

A minimum-impact, flexible tool to study vocal communication of small animals with precise individual-level resolution

1.To understand both proximate and ultimate factors shaping vocal communication, it is fundamental to obtain reliable information of participating individuals on different levels: Firstly, it is necessary to separate and assign the individuals’ vocalisations. Secondly, the precise timing of vocal events needs to be retained. Thirdly, vocal behaviour should be recorded from undisturbed animals in meaningful settings. A growing number of studies used animal-attached microphones to tackle these issues, but the implications for the study species and the research question often receded into the background. Here we aim to initiate a discussion about the limitations, possible applications and the broader potential of such methods. 2. Using lightweight wireless microphone backpacks (0.75 g including customised leg-loop harness) combined with multi-channel recording equipment we captured vocal behaviour of small songbirds. We evaluated the effect of the devices at various levels, including an assessment of how vocal and locomotor activities were affected by initial device attachment and battery exchange. We compared our approach to existing studies and identified suitable research examples. 3. We acquired continuous vocalisation recordings of zebra finches, and unequivocally assigned them to interacting individuals, with system-based synchrony, irrespective of background noise. We found effects of initial backpack attachment and of battery replacement on vocal and locomotor activity, but they were minimised through the extended recording duration (ca. 16 days) that outlasted habituation effects (ca. 3 days). 4. This method provides the tools to integrate individual vocal communications into a group setting, while enabling animals to behave freely in undisturbed, structured and acoustically complex environments. By minimising the effects on the animals, the behaviour under study, and ultimately on the research question, this approach will revolutionize the ability to capture individual-level vocalisations in a variety of communication contexts, opening up many new opportunities to address novel research questions

Number of answers data

Here you find the data for: 1 - the total answers analysis for the complete playback series, 2- the supplementary analysis of the number of answers during the first 30 calls of the playback series and 3 - the supplementary analysis of the number of answers during the last 30 calls of the playback serie

Latency data

Here you find the data for: 1- the latency analysis for the complete playback series, 2- the supplementary analysis of the latency for the first 30 calls of the playback series and 3- the supplementary analysis of the latency for the last 30 calls of each playback series

baseline vs. experiment comparison

File containing the proportion of 'stack' calls used as answer during the baseline recordings and both experimental trials