The finding of algae on a beach in Antarctica, which have crossed more than 20,000 kilometers to arrive at that shoreline, is the best-known example of a biological dispersal on the record.
In order to arrive there, the algae had to traverse barriers caused by polar winds and streams that, up to this point, were thought to be impermeable.
The discovery signifies that Antarctica is not as remote from the world as the researchers believed, which has repercussions on how Antarctic ecosystems will evolve as a result of global warming.
The report, released in Nature Climate Change, refers to the finding of Chilean researcher Erasmo Macaya of the University of Concepción, who accidentally found a few algae laid down by the ocean on an Antarctic beach.
Storms of Antarctica can indeed help biological dispersal to happen
“This finding shows us that live plants and animals can reach Antarctica through the ocean, with temperate and sub-Antarctic marine species probably bombarding Antarctic coasts all the time,” explained the study’s leading author Crid Fraser from the Australian National University (ANU).
“We always thought Antarctic plants and animals were different because they were isolated, but this research suggests that these differences are almost entirely due to environmental extremes, not isolation,” the scientist added.
In the opinion of a co-author of the study from the ANU and the ARC Center of Excellence for Climate Extremes (CLEX), Adele Morrison, who directed the oceanographic studies, powerful westerly winds and surface streams are likely to carry floating objects north and far from Antarctica. But when the upheaval of the Antarctic tempests is considered, all that changes and biological dispersal becomes possible, such as in the case of the algae that reached an Antarctica beach.
“Once we incorporated wave-driven surface movement, which is especially pronounced during storms, suddenly some of these biological ponds were able to reach the Antarctic coast,” Adele Morrison said.