The Odds of Arctic Lichens Surviving Dramatic Global Warming

With respect to concerns about the future of earth's biosphere, and especially those components of it that currently reside in the Arctic, Geml et al. (2010) declare that "the ability to migrate is of particular importance, because climate warming is expected to cause a northward shift in the distribution of many Arctic species, and the long-distance dispersal capability of individual species will greatly influence the composition of future Arctic communities."

In an assessment of the ability of two Arctic-alpine lichens to cope with such a dramatic eventuality, the authors examined the genetic structure and long-distance gene flow in two lichenized ascomycetes -- Flavocetraria cucullata and F. nivalis -- which are widespread in Arctic and alpine tundra. This they did via DNA sequencing of 49 specimens of F. cucullata and 41 of F. nivalis that were collected from various locations throughout Europe, Asia and North America, employing "phylogenetic, nonparametric permutation methods and coalescent analyses" to assess "population divergence and to estimate the extent and direction of migration among continents."

The four researchers report that both F. cucullata and F. nivalis had "high and moderately high intraspecific genetic diversity, respectively," and that "clades within each species contained specimens from both North America and Eurasia."

Geml et al. conclude that "at least some Arctic lichens have strong potential to adapt to the changing Arctic by tracking their ecological niche and to maintain high genetic diversity through intercontinental dispersal and sexual reproduction." Consequently, whatever nature -- or man -- may ultimately be responsible for sending their way in terms of global warming, Arctic-alpine lichens should be good to go ... wherever it is they need to go.