The Arctic and Antarctic regions don’t seem to offer the friendliest conditions for life forms to thrive, but in reality they host quite a variety of species. It has long been believed that, since being separated by a considerable 11,000-kilometer distance, the North and the South oceans had nothing in common in terms of animal species, but the latest study from Census of Marine Life researchers proves otherwise.
The researchers found at least 235 species that appear to be common to both regions, including grey whales, birds, crustaceans, and other species. While there is still no confirmation that the species are indeed identical, their presence in both regions could be explained through a phenomenon responsible for global shifts at all levels: global warming.
The polar seas, far from being biological deserts, teem with an amazing quantity and variety of life, Dr. Ian Poiner, Chair of the Census Scientific Steering Committee, explained. Humanity is only starting to understand the nature of these regions.
The new study changes the general view on the Antarctic region, which was previously believed to be poor in species diversity and abundance. The researchers have managed to retrieve biological data from over 1 million locations, including seafloors that only recently have been exposed to life, as the100,000-year-old ice shelf lids began melting.
The Antarctic seafloor is now described as a single biological province, unlike 40 years ago, when separated bioregions were described. Researchers explained that the challenge now is to establish whether this biological redistribution has been influenced by changes in the Antarctic Circumpolar Current.
Last year, scientists from the Census of Marine Life reported that they’ve managed to link most of the deep sea octopus species we see today to a common Antarctic ancestor, which surprisingly enough, can still be found in the Southern Ocean. Scientists revealed that 30 million years ago, octopuses living in the Antarctic water started migrating, as their habitat began cooling and the ice sheet grew, forcing them to occupy new ocean basins. But as they started migrating, the conditions they met in the new habitats also triggered evolution differences, visible today.
The Arctic region has also been under extensive observations, as changes in the ocean temperatures produce major ruptures in the ice shelf, and alters the marine life distribution here. Researchers noted that larger marine species are now being replaced by smaller ones, a phenomenon that they are still trying to find an explanation for.
Dr. Ian Poiner also said: In these unique oceans, where the water temperature is colder at the surface than below, we are establishing the first benchmarks of marine biodiversity against which change may be measured, a significant polar year legacy for future generations.
Scientists are now using the latest technologies to conduct a more detailed research into the distribution and abundance of marine life. This includes tracking devices, deep water optical systems on Remotely Operated Vehicles (ROVs ), DNA sequencing and more. The first ever marine life census is expected to be released in 2010.
