Horseshoe crab is one of the oldest living things in the world. It is an arthropod in the ocean, and its body is mostly blue-brown and dark brown. This creature has been developed from the earth and has existed for hundreds of millions of years. Its ancestors can be traced back to the Cambrian long ago. This horseshoe crab, which looks like a shrimp and crab, is very rare because of its small number.

First, the value of horseshoe crabs

Horseshoe crab is one of the ten oldest known species on the earth with a long history. In addition, it also has very rich scientific value. It has four eyes and two small eyes in front of the head and breastplate. These two small eyes can perceive brightness and are very sensitive to ultraviolet rays. On both sides of the head and breastplate, there are a pair of compound eyes, similar to several small eyes. In daily life, radar and TV systems rely on the inhibition of horseshoe crab's compound eye side, which can make the influence of objects more clear.

Besides its eyes, its blood also has special value. The blood of horseshoe crab contains a lot of copper ions, which can make the blood coagulate rapidly and is also an important part of body defense. In real life, its blood can be used as a bacterial detector, which can accurately detect living bacteria or special cells, and can also detect endotoxin secreted by bacteria.

Second, the life habits of horseshoe crabs

Most horseshoe crabs live on the shore, but the water is deep. They are not very good at swimming. In the water, they often just beat the water surface with the beat of their bodies, or crawl on the bottom of the soft mud, which is very slow. The main food is some small ha or tiny larvae.

Every year in the spring season, mature horseshoe crabs migrate to the seaside to lay eggs. The female crab will lay 200-300 eggs in the pit on the beach, which will be fertilized by the male crab and then let it develop on its own. In the process of migration, many horseshoe crabs are very difficult in the process of migration, because their fragile and soft bodies are overturned by the waves, and then they can only be called the prey of seagulls.