An Arctic refugium under assault Cyrus Martin  Current Biology  Volume 23, Issue 23, Pages R1020-R1022 (December 2013) DOI: 10.1016/j.cub.2013.11.018 Copyright © 2013 Terms and Conditions

Ominous signs: A new study reports that the diatom populations of several lakes in the Hudson Bay Lowlands have undergone synchronous changes that coincide with a recent rise in temperature. There is a worry that these changes will cascade through the food web, possibly affecting many species. Top panel: an aerial photograph of lakes typical of the region. (Photo courtesy of Kathleen Rühland.) Bottom panels: examples of diatoms, microscopic algae that adopt a huge variety of intricate shapes. The bottom-left panel is Diploneis sp. and the bottom-right panel is Navicula sp. (Images courtesy of Daniel T. Selbie and Kathleen Rühland, respectively.) Current Biology 2013 23, R1020-R1022DOI: (10.1016/j.cub.2013.11.018) Copyright © 2013 Terms and Conditions

A heat refuge no more: While the rest of the world warmed in the 20th century, the Hudson Bay Lowlands of northern Canada (indicated by the red dot in the left panel) remained cool until the early 1990s. But with the loss of sea ice in the Hudson Bay, and with it the region’s heat shield, temperatures have skyrocketed. The loss of ice and rising temperatures threaten many species in the region, such as the iconic polar bear (right). (Left: Photo courtesy of NASA/Goddard Space Flight Center Scientific; Right: Photo courtesy of Jon Sweetman.) Current Biology 2013 23, R1020-R1022DOI: (10.1016/j.cub.2013.11.018) Copyright © 2013 Terms and Conditions