Experimentally created Antarctic cryoconite holes
We used an in situ manipulative experiment to test whether the order in which community members arrive determines the composition of microbial communities on glaciers in the Dry Valleys of Antarctica. Here we show that strong priority effects were evident after the first growing season on the glacier, but that these effects were dampened after a second growing season likely due to strong selection by the harsh environment. These findings broaden our understanding of factors driving the biodiversity of the cryobiosphere at a time when it is severely threatened by global warming.