First of all, let's talk about the first situation, that is, the theory of extinction in the process of natural evolution. Mixed-winged horseshoe crab itself is a very large aquatic creature, and it can survive in fresh water, salt water, shallow water and deep water, so mixed-winged horseshoe crab is actually a very special creature, but the evolution of large animals itself is difficult. Many large animals are actually extinct in the process of natural evolution, because the cells in their bodies have changed.
Secondly, some scientists believe that the living environment of mixed-winged horseshoe crab is CAMBRIAN, when all water sources should be warm and absolutely sterile. As a creature accustomed to living in sterile environment, mixed-winged horseshoe crab has not evolved the ability to adapt to water sources after the water sources gradually changed, so it will gradually become extinct. However, this statement is actually partly due to natural evolution. Simply put, the evolution of mixed-winged horseshoe crab can't keep pace with environmental changes, so it was extinct.
Finally, because the mixed-winged horseshoe crab was extinct before human beings evolved, the argument that human activities led to the extinction of mixed-winged horseshoe crab was basically ruled out. Now that Chinese scientists have successfully found the fossils of mixed-winged horseshoe crab, the mystery of the extinction of mixed-winged horseshoe crab will surely be gradually solved.