Niederberger et al. 2008

Neiderberger TD, McDonald IR, Hacker AL, Soo RM, Barrett JE, Wall DH, Cary SC. 2008. Microbial community composition in soils of Northern Victoria Land, Antarctica. Environmental Microbiology 10: 1713-1724.

These authors present an analysis of a large collection of data regarding both microbial and metazoan biodiversity at relatively small scales in one part of Taylor Valley, Antarctica, one of the famous Dry Valleys. This contributes to both the Latitudinal Gradient Project, an international effort to characterize Antarctica, and to the biogeographical debate regarding the distribution and community assemblages of microbes and soil microfauna.

Biodiversity was higher than expected based on the physical characteristics of this extreme environment, and was much more variable at small (~200m) spatial scales. While the microbes identified by 16s sequences were not particularly surprising, the changes in community composition between study sites was high. This supports the hypothesis that extreme environments “select for” particular microbial physiologies, and that differences in soil physical features such as moisture and temperature are highly important, in distinct contrast to the “everything is everywhere” hypothesis of microbial biogeography.


NB October 1 2009: the “everything is everwhere” hypothesis (Beijerinck 1913) includes the second clause “the environment selects”, which implies my earlier impressions, above, are incorrect. This paper’s demonstration that extreme environments select for particular soil communities, and that local-scale variables such as moisture and temperature, rather than regional-scale variables such as climate factors, actually supports Beijerinck’s (1913) hypothesis, rather than countering it.