Diverse hypolithic refuge communities in the McMurdo Dry Valleys

• Published in: Antarctic Science
• Main Authors: Cowan, Don A., Khan, Nuraan, Pointing, Stephen B., Cary, S. Craig
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2010
• Subjects: Antarctic; cryptic; cyanobacteria; hypoliths; microbial diversity; McMurdo Dry Valleys; Antarc*; Antarctic Science
• Online Access: https://hdl.handle.net/10289/5090; https://doi.org/10.1017/S0954102010000507

Hyper-arid deserts present extreme challenges to life. The environmental buffering provided by quartz and other translucent rocks allows hypolithic microbial communities to develop on sub-soil surfaces of such rocks. These refuge communities have been reported, for many locations worldwide, to be predominantly cyanobacterial in nature. Here we report the discovery in Antarctica’s hyper-arid McMurdo Dry Valleys of three clearly distinguishable types of hypolithic community. Based on gross colonization morphology and identification of dominant taxa, we have classified hypolithic communities as Type I (cyanobacterial dominated), Type II (fungal dominated) and Type III (moss dominated). This discovery supports a growing awareness of the high biocomplexity in Antarctic deserts, emphasizes the possible importance of cryptic microbial communities in nutrient cycling and provides evidence for possible successional community processes within a cold arid landscape.