Generally speaking, crabs with fuller bellies and more crab yolk are good crabs, but some crabs have bulging bellies, are not large, are lightweight, and are almost empty of meat. It turns out that the yellow bulging part of the crab's abdomen is not crab yolk, but part of a parasite called crab slaves. Crab slaves are parasitic organisms that live on crabs and are a type of barnacle organism. Generally speaking, a barnacle's parasitism doesn't have much of an effect on the host, the two are **** perched in a relationship, meaning that the barnacle obtains nutrients from the host, but it exists and the host is unaffected by it. However the crab slave is completely different, it is the complete predator. The development of crab slaves is very similar to that of other barnacles; when they first hatch, crab slaves look more like crabs, and at this point they are able to move around freely and will prey on plankton in the ocean. As they develop, they have a hardened outer shell that helps them resist attacks from predators, but at this time they are less resistant and less able to forage for food. In order to survive and avoid natural enemies, crab slaves at this time will search for crabs in the ocean. It is known that about 50% of the crab slaves' hosts are crabs, so people call them crab slaves, except that they are not slaves of the crabs, but the crabs are their slaves. When they seek out the crab, they enter the crab along the joints of the crab's body, or where it is injured, and of course the hardened shell comes off on the outside. When they have just entered the crab, they are still relatively weak, and at this time the crab does not feel their presence at all. But they will stick out root-like branching protrusions in the crab's body, and these protrusions can connect all parts of the crab's body, hogging the nutrients in the crab's body and attributing them to themselves. Moreover, crab slaves do not have a solid form, they are like fungal hyphae that spread to all parts of the crab, including the pincers and the head position. At this time, if we have a pair of perspective eyes, we will find that the crab is not a crab, but the "zombie crab", their bodies are not controlled by themselves, but the crab slaves in control.