The only animal with blue blood has survived for 300 million years. Why did you escape extinction?

If I say that there are blue-blooded animals, everyone may be surprised and think that I am joking; But in fact, there is such an animal. Its name is horseshoe crab (h? U). Animals that look like crabs. Some people habitually call it horseshoe crab. They are the only animals with blue blood on the earth, and it is precisely because of this unique blood that horseshoe crabs are extinct. Due to our over-hunting, this ancient species on the earth is on the verge of extinction and has been listed as a national second-class protected animal.

I personally have only seen people or animals with blue blood in the young King Wesley. In this sci-fi TV series, Wesley, the hero, was born in a famous family. After watching this TV, I once thought that there really were blue-blooded human beings in the world. I didn't know until I grew up that blue-blooded people don't exist, but there is one kind and only one kind of blue-blooded animals.

After discovering that horseshoe crabs are different from other species on our planet, scientists began to study the secret of horseshoe crabs' blue blood, and finally solved the mystery with the cooperation of all scientists, Qi Xin. It turns out that horseshoe crabs contain a lot of copper in their blood, which makes their blood blue. Just as human and other animals have iron in their blood, iron can make our blood appear bright red.

Although horseshoe crabs have experienced the extinction of the earth, they have never been defeated in these cruel natural environments; They survived to the age of our human civilization, but they still failed to escape human pursuit. All this stems from their aristocratic lineage. On the one hand, people are very curious about their blue blood, and the status of paleontology makes people think that eating more of them can prolong life. On the other hand, because they are really delicious, people are eager to catch them.