There are places on our planet where life seems impossible. Antarctica is one of them. But this was not always the case: 68 million years ago, the continent was covered with dense forests, along which dinosaurs and the first mammals walked. In those days, Antarctica was connected with South America, forming the last remnants of the supercontinent Gondwana, from which Africa and Australia had already separated. Only after the breakaway from South America – about 35 million years ago – the continent was enveloped in ice cover, which destroyed almost all life. Of course, Antarctica is famous for penguins and seals, but they live on the coast, eating fish and phytoplankton. But they cannot survive in the depths of the continent, about 98% of which is covered with ice. It was believed no one can. Until recently.
Who lives in Antarctica?
Beginning in about 1900, scientists gradually discovered that ice-free plots of land a few kilometers from the coast were inhabited by tiny creatures called Collembole – a subclass of small arthropods – ticks, worms, and even midges. All these creatures needed water and often inhabited small areas of lichens or moss on the northern slopes, where the summer sun melted snow and moistened the soil 24 hours a day. But over time, researchers found them in colder and drier places, moving deeper into the mainland, until they found Tullbergia – a tiny animal living under rocks in the inland mountains of Antarctica.
In fact, few have heard of collembolas. And this is despite the fact that the soil in the yard where you live is probably just teeming with them. These tiny creatures are found all over the world, and several species live in rare areas of ice-free surfaces that are scattered throughout Antarctica. However, this is a very harsh place where there is little food, with the exception of microscopic fungi and rare bacteria. How the collembolans and Tullbergia ended up there and how they survived dozens of ice ages is a mystery, the answer to which is yet to be found. And how do you think these tiny ancient animals managed to survive in such an aggressive and cold environment? Share your opinion with the participants of our Telegram chat, there you will find like-minded people.
A study published in the journal Pedobiologia in 2005 showed that the age of origin of some Antarctic collembolls is much greater than past ice ages. To evaluate when several species of Antarctic collembollas shared with species from Australia, New Zealand, and Patagonia, scientists used DNA analysis. The results were unexpected – judging by the data obtained, the separation occurred from 10 million to 20 million years ago. Read more about what DNA analysis is, how it is made and why it is needed, read in our material.
Not surprisingly, these results left researchers confused: how did these tiny creatures survive so many ice ages? Some have suggested that animals could survive in various small isolated valleys called the McMurdo Dry Valleys, in the northern Transantarctic Mountains, but no one knows the exact answer to this question today.