The article, Kelp genes reveal effects of subantarctic sea ice during the Last Glacial Maximum, describes an experiment designed to measure the extent of sea ice in the Southern Hemisphere during the Last Glacial Maximum (LGM). Prior to this study, paleogeographers had yet to conclusively determine the extent of sea ice in the Southern Hemisphere during the LGM, so this experiment contributed greatly to the advancement of the paleogeographic field. The authors of this article have also pioneered a new method of study in this field; they were the first paleogeographers to examine modern genetic data to draw conclusions about past conditions and climate in the Southern Hemisphere (Fogarty, 2009). The authors used mitochondrial and chloroplast genetic markers (COI; rbcL) to genetically examine 300 algal samples from 45 different locations across the Southern Ocean. They then used these results to approximate how long the algae have been in that area; if the algae showed genetic homogeneity, then it suggested that the algae had recently colonized the area, and if they had not, then it suggested that that population of algae had been there for a comparatively longer period of time (Fraser et al., 2009). Since D. antarctica cannot survive ice erosion, it is inferred that areas where the algae appear to have recently colonized were affected by ice erosion during the LGM. As a result of the experiment, the authors found that their data suggested that ice cover during the LGM extended over a much larger area than previously assumed. In the article, the authors provide a diagram containing the results of their genetic characterization of algae on page 2. The figures are organized into a phylogenetic tree. The purpose... half of the paper... Reveal the effects of subantarctic sea ice during the Last Glacial Maximum." Proceedings of the National Academy of Sciences 106.9 (2009): 3249-253. Print.Fraser, Ceridwen I., Martin Thiel, Hamish G. Spencer, and Jonathan M. Waters “Contemporary Habitat Discontinuity and Historical Genetic Divergence of Glacial Ice in the Evolutionary Biology of the BMC 10.1 (2010): 203. Print.Hinojosa, Iván A., Matías Pizarro, Marcel Ramos and Martin Thiel. "Spatial and temporal distribution of floating algae in the channels and fjords of southern Chile." ENDEMICS OF THE SUBANTARCTIC ISLANDS AMERICAN JOURNAL OF BOTANY 98.1 (2011). November 13th. 2011.