Polar bears only live in the Arctic.
REPUBLIKA.CO.ID, JAKARTA — Continent Arctic and Antartika have similarities and differences. Both are located at the ends of the Earth. Well, one of the differences that is quite noticeable is that the two are home to very different creatures.
Although both poles are home to various species of seals and whales, only the North Pole is home to the largest bear on Earth, the polar bear.
Around the Arctic Circle, polar bears (Ursus maritimus) and its cubs can be seen in Alaska, Canada, Greenland (part of Denmark), Norway, Russia, and, on rare occasions, Iceland. Hair polar bears designed to withstand temperatures as low as minus 22 degrees Fahrenheit (minus 30 degrees Celsius). They spend most of their lives on ice, feeding on seals rich in fat that keeps them energized between meals.
Sea ice, cold temperatures, and seals can all be found in Antarctica. So, why are there no polar bears on the world’s southernmost continent? The answer has to do with the evolution and geological history of the Earth.
“Bears are fundamentally a phenomenon in the Northern Hemisphere,” according to Andrew Derocher, a professor of biological sciences at the University of Alberta in Canada who has spent nearly 40 years studying polar bears. Live Science.
Bears are found only in the northern hemisphere, with the exception of the Andean bear (Tremarcto ornaments) from South America. There is no particular reason for this. Simply put, some species evolve in certain locations while others do not.
“Biogeography is full of strangeness.”
“Some species make it to new locations, while others don’t.” said Derocher.
There has never been a time in the evolutionary history of polar bears when the North and South poles were held together by ice. Polar bears are known to be the largest land carnivores in the world, although they are by no means land animals.
Great white bears spend most of their lives on sea ice and only occasionally come to shore to breed. Polar bears are a relatively new species in terms of evolution. They are descended from the ancestor of the brown bear (Ursus arctos) between 5 million and 500,000 years ago, Derocher said.
However, because the continents were in the same place 5 million years ago as they are today, polar bears never had the chance to move from pole to pole. The southern tip of South America, which includes Chile and Argentina, is the closest landmass to Antarctica. If moving, polar bears must travel the treacherous Drake Trail to reach Antarctica. When cold waters from the south meet warm waters from the north, the area is known for violent storms and fierce seas.
But if the polar bears were given the chance, would they be able to survive at the South Pole? For Derocher, the answer was simple: “They’re going to have fun in Antarctica.”
Polar bears eat seals and the occasional Arctic bird or egg. With six species of seals and five species of penguin, Antarctica is rich in all three.
Furthermore, neither of these creatures evolved to fear massive land predators. Polar bears will perceive the Antarctic terrain as a free expanse for all, which is why no one should take a polar bear there. Their insatiable appetite, coupled with the local fauna’s lack of awareness of massive terrestrial predators, is likely to result in ecological collapse. Maybe it would be better if the great white bear stayed north.
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