Abstract

How long has life persisted on Antarctica? Glaciological reconstructions estimate that thick ice sheets covered most terrestrial areas of Antarctica during the Last Glacial Maximum (~22–18ka), as well as previous glaciations, suggesting no life could have survived on land during these periods. However, recent studies show most groups of the contemporary Antarctic terrestrial biota have a hundred thousand to multi-million year persistence on the continent. The most dominant group of Antarctic flora – the bryophytes (mosses) – seem to stand distinct from these patterns. Their low species number, low endemism levels, and distribution patterns suggest that today’s moss biota are recent colonists. Alternatively, bryophytes may have a long persistence in Antarctica, but their presence has previously been underestimated. Here, focusing on the cosmopolitan species Bryum argenteum, we present the first evidence of long-term in situ persistence of mosses in Antarctica. Using population genetic methods, we found the first evidence for multi-million year persistence of bryophytes in Antarctica. This study suggests that, despite low endemism levels, mosses may have had a much longer persistence in the Antarctic than previously thought.