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A group of crustaceans inhabit almost all aquatic ecosystems and have attracted the attention of Chilean researchers (Mundo Acuícola).
Copepods, also known as "super-crustaceans", surprise by their great resistance and their great adaptability to extreme environments. Today, they provide clues to the rare terrestrial and freshwater fauna of the white continent and its connection to South America.
Its small dimensions do not prevent their distribution throughout the planet. They are part of zooplankton in marine and freshwater environments, in addition to playing a fundamental role in the food chain and indicating environmental changes. It is a group of crustaceans that lives in almost all aquatic ecosystems and has caught the attention of Chilean researchers
. Therefore, through the Ministry of the Environment, 14 species of copepods of the genus Boeckella have been recorded. They live in Chilean and Argentine Patagonia, in the sub-Antarctic islands and in Antarctica. The work was prepared by scientists from the Institute of Ecology and Biodiversity (IEB), the University of Chile, the University of Magallanes, Costa Humboldt and the British Antarctic Survey (United Kingdom), to facilitate research and to democratize access to data on freshwater biodiversity that is not well explored.
"The terrestrial or freshwater fauna of Antarctica is very rare and reduced in relation to marine biodiversity, since there are no mammals, d 39; amphibians or reptiles and that there is only one species of bird.Also, many believe that the entire continent is frozen but has the greatest diversity of systems of liquid water, such as fjords, lakes, among others, where copepods live, "says Claudia Maturana, a scientist at the Institute of Ecology and Biodiversity. receives support from CONICYT and the Chilean Antarctic Institute for its research.
Although Magellanic and Antarctic lakes are generally oligotrophic, that is to say that they have few nutrients, they also differ from one to the other. other.
Although Patagonia is richer in Boeckella species, it is found only on the white mainland Boeckella poppei. It is precisely this latter species that has aroused the interest of scientists to be the only invertebrate present in the continental lakes of Antarctica, the Antarctic Peninsula and sub-Antarctic islands.
"Although on the white continent are other copepods dulce, Boeckella poppei is the only crustacean also present on this territory", explains Maturana, who exposed some of them a few years ago days at the Natural History Museum in London.
One of the main characteristics of these animals is their great resistance and adaptability. To get an idea, this arthropod has an intense red color that protects it from UV rays and inhabits deep, deep lakes that connect to marine waters or in smaller, shallower ecosystems that feed on ice melt. at temperatures below 5 ° C and even below 0 ° C.
"This animal may remain in the state of the egg for many years, as it hibernated, to survive in extreme conditions.In winter, for example, the Antarctic lakes are frozen.To subsist, you can go to the depths or lower your metabolism. "
The IEB researcher adds: "In 2012, a team of Chinese scientists badyzed the sediments of a lagoon near its Antarctic base and detected viable eggs from Boeckella poppei 100 years old and hatching at any time."
Trained by the whaling industry?
Currently, one of the big questions is how Boeckella poppei became one of the few representatives of terrestrial and freshwater fauna l & # 39; Antarctica.
"There is no certainty about what happened when the continent pbaded through the last great glaciation more than 20,000 years ago, and Maturana believes that some species have survived through shelter. (19659003) Considering its wide distribution in the Antarctic, Boeckella poppei is a model to test the two previous hypotheses.
The big question is whether this copepod has colonized the continent the most southerly of the Earth from Patagonia or the sub-Antarctic islands, or where he has managed to survive by taking refuge in isolated places during the ice ages and climatic changes over millennia.
that there is a link between the populations of Boeckella poppei of Antarctica and Patagonia, this would not be very recent since it would exceed 20 000 years. , the way in which these organisms are moving has not been clarified yet. Some of the possible explanations suggest that seabirds traveling between the two continents could become vectors during the movement of these crustaceans
. The crew of ships extracted freshwater Antarctic lagoons, which were stored in barrels for consumption and for other purposes. Therefore, when transporting or emptying containers with liquid, cetacean hunters were able to move the copepods to places where they were not previously. "The populations of Antarctic copepods remain very virgin and little intervened." We have not detected greater human impact, "says the scientist.
Despite its obvious attributes of" super crustaceans ", there is no clear idea of the mechanisms of differentiation and adaptation to different ecosystems, the ones he lives in. An example is that some people have experienced a reduction in the size of their body and their body. Fertility of females, in response to less availability of resources on the Antarctic continent
"Although their role has been studied animals as sentinels of climate change or as indicators of the quality of the water, research on evolutionary models of freshwater fauna has been little explored. That's why it's important to generate and provide information from Chile to learn about biodiversity in freshwater at high latitudes, "said Maturana.
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