Why are there no penguins in the Arctic?

In fact, a penguin lived in the North Pole a long time ago, but now it is extinct. Known as the "Arctic Giant Penguin", this penguin is 60 cm tall, with a brown head and black feathers on its back, much like a foreign gentleman in an evening dress. They live in what is now Scandinavia, Canada and northern Russia, as well as all the Arctic and subarctic islands. At the peak, the number reached several million.

About 1000 years ago, the vikings discovered giant penguins. From then on, the bad luck of the big penguin came. Especially after the16th century, the arctic exploration fever rose, and giant penguins became the hunting targets of explorers, navigators and aborigines. Long-term hunting and indiscriminate killing led to the complete extinction of Arctic penguins in 1844.

The ancestors of penguins living in the Antarctic today developed in areas south of the equator. Scientists speculate that the reason why they don't continue to push north to the northern hemisphere may be that penguins can't stand warm tropical waters. The northernmost limit of their distribution range is very consistent with the connection line of the area with an annual average temperature of 20℃. The equatorial warm current and high temperature form a natural barrier, which prevents penguins from crossing the equator to the north. They must stay in the waters where Antarctic ice and snow melt or deep-sea cold water passes. At present, there are about 20 species of penguins in the world, all of which are distributed in the southern hemisphere, with the Antarctic continent as the center and the southern tip of North Africa, South America and Oceania as the center, mainly distributed in the mainland coast and some islands.

The * * * isomorphic features of Antarctic penguins are: streamlined body, black feathers on the back, white feathers on the abdomen, flippers, thin tubular feathers, needle-like arrangement, short legs, webbed toes, short tail, fat body, big belly and stumbling.