English practice 41

Antarctica's Adaptable Survivors

Many inhabit sporadic green patches of moss;⁶¹ fertilized by excrement from migrating birds and sheltered by the rocky mountainsides. Some hibernate in the winter, frozen in ice under rocks and stones, becoming active⁶² again when the climate warms and the ice is melting.⁶³ Extreme cold and wind are all good to go for survival;⁶⁴ indeed, some species are able to endure temperatures as low as ?30 degrees Celsius. These adaptable invertebrates classified as arthropods;⁶⁵ are able to survive on a continent once thought to arctic, to windy, and to icy,⁶⁶ to maintain any permanent land animals. The coldest place on earth, Antarctica is home to great quantities of life that don't simply tolerate the lower temperatures; they⁶⁷ flourish in them.

Microscopic mites, springtails, and wingless midges accompanied⁶⁸ lice and ticks as the most prevalent permanent land fauna on Antarctica. The tiny midges and mites tolerate the cold due to the antifreeze liquid they carry in their bodies. Parasitic lice and ticks seek shelter from the harsh climate in the warm fur of seals, the waters of Antarctica teeming with marine life,⁶⁹ and the feathers of sea birds and penguins.

In the Dry Valleys located on the western coast of McMurdo Sound in Antarctica, nematode worms feed on bacteria, algae, and tiny organisms known as rotifers and tardigrades. Here, ice-covered land is not as abundant.⁷¹ Beneath the moss-covered polar rock, nematodes thrive, coping ingeniously by dehydrating themselves in the winter with the low temperatures⁷² and coming back to life with the summer and increasing moisture.

Algae are another resilient life form of the Dry Valleys of Antarctica.⁷³ In an effort to adjust to the strong winds and icy temperatures, some algae live inside the rocks as opposed to on top of them. Phytoplankton, the most common of Antarctica's algae, is an important food resource within Antarctica's ecosystem. These tiny free-floating plants are preyed upon by copepods and krill, which then provide food for fish, seals, whales, and penguins.

Excluding its aquatic life, Antarctica has a lower species diversity than any other place on earth. Nevertheless,⁷⁵ Antarctica is a haven for 67 documented species of insects and 350 species of flora, proof that life persists in the most dramatic of conditions.