Some of the coldest and driest permafrost soils on Earth are located in the high-elevation McMurdo Dry Valleys (MDVs) of Antarctica, but little is known about the permafrost microbial communities other than that microorganisms are present in these valleys. Here, we describe the microbiology and habitable conditions of highly unique dry and ice-cemented permafrost in University Valley, one of the coldest and driest regions in the MDVs (1700 m above sea level; mean temperature −23 °C; no degree days above freezing), where the ice in permafrost originates from vapour deposition rather than liquid water. We found that culturable and total microbial biomass in University Valley was extremely low, and microbial activity under ambient conditions was undetectable. Our results contrast with reports from the lower-elevation Dry Valleys and Arctic permafrost soils where active microbial populations are found, suggesting that the combination of severe cold, aridity, oligotrophy of University Valley permafrost soils severely limit microbial activity and survival.
Healthy individuals display a tendency to allocate attention unequally across space, and this bias has implications for how individuals interact with their environments. However, the origins of this phenomenon remain relatively poorly understood. The present research examined the joint and independent contributions of two fundamental motivational systems – behavioural approach and inhibition systems (BAS and BIS) – to lateral spatial bias in a locomotion task. Participants completed self-report measures of trait BAS and BIS, then repeatedly traversed a room, blindfolded, aiming for a straight line. We obtained locomotion data from motion tracking to capture variations in the walking trajectories. Overall, walking trajectories deviated to the left, and this tendency was more pronounced with increasing BIS scores. Meanwhile, BAS was associated with relative rightward tendencies when BIS was low, but not when BIS was high. These results demonstrate for the first time an association between BIS and lateral spatial bias independently of variations in BAS. The findings also contribute to clarify the circumstances in which BAS is associated with a rightward bias. We discuss the implications of these findings for the neurobiological underpinnings of BIS and for the literature on spatial bias.
