How to become the most beautiful crab at the sea?Anemone: I'm here to help you make styles

Except for coconut crab, most of the herd crabs growing hard shells, most of the shelter crabs have no protective shells, and only a soft body is exposed. Therefore, they need to find shells to protect themselves. Generally speaking, HP crabs will give priority to choosing conch shells. After all, they are solid and durable second -hand houses.

But there is a class of home crabs. They do not choose hard conch composed of calcium carbonate. Instead, they choose living animals composed of muscle and mucus: anemone.

Cool "tentacle jacket" -aneys

This strange combination was found on the bottom of Japan. Dozens of "tentacles" on the head of Pagurodofleinia Doederleini were anemone. This anemone has long been known by the Japanese and gave it a name -Ji Jinkara anemone (note that anemone looks like a plant, which is actually a predation animal). But it has not been recognized as independent species academically until it has recently appeared on academic journals with its partners.

Picture source: Akihiro Yoshikawa

A scientist gave a fair name to aflowers: Stylobates Calcifer, Stylobates, which means "columns", is a specifically used in ancient Greek Roman columns. The noun of the pillar bottom platform describes the shape and function of the anemone in its image -the tentacles are similar to the pillars, and there is also a few pilot structures similar to the base that can be fixed on the home crab.

Cassifer may be more familiar with it. It is the role of Hald Mobile Castle, a fire demon signed with Hal. With the contract, Hal and Casifa are similar to mutual benefit and symbiosis. Cassifa has Hal's heart, while Halfa asked Cassifa to move the castle for him.

Hal and Casifutu Source: Hal's Mobile Castle

The aquarium in reality has a red tentacle, which looks similar to the red flame in Cassifer. At the same time, there are similar relationships in the real estate crabs and anemone in reality, but it is not a magic contract, but purely mutual use.

Fight! Living crab!

In 2020, a scientist brought a pair of home crabs and anemone back to the laboratory, put it in aquarium with flowing sea water, and observed how they lived together.

At the beginning, scientists have not let her home crabs put on a "tentacle jacket", but given it a flat conch (Glossaulax Reiniana). At this time, anemone is also attached to a shell. After a while, they put them together.

Ordinary conch shell for the first -to -home crab source: vianet Conchology

Sure enough, the hermit crab also likes the new and hates the old. When it saw the anemone, it immediately climbed over and wanted to take off the conch on the body and put on the cool "tentacle coat".

After seeing the anemone with a conch on the back, I couldn't wait to change the picture of a new house. Source: Akihiro Yoshikawa

But the shell change is not as easy as expected. On February 20, 2020, the first time to see the Casifa Anemma in the laboratory, I wanted to let the anemone attach it on myself as soon as I met.

Akihiro Yoshikawa

The home crab climbed to the anemone first, and quickly tapped with the front touch of the front, while pinching the anemone with chewing, like a massage for it. "Massage" is rhythmic, about 6 times per minute.

I am trying to "persuade" anemia from my own home crab. Source: Akihiro Yoshikawa

In this way, it was not successful for 12 hours to make a crab for 12 hours. After all, anemone is a living creature, and the twisted melon is not sweet, not you just want to change it. After the failure, the residence crab returned to the previous shell.

But for the first time, the unsuccessful home crab did not give up, and the tentacle of the new home was still very tempting to it. On February 28, 2020, the hermit crab tried again, the same massage technique, the same deed. This time, after 43 hours of the crab flowers, the anemone was finally removed from the shell.

After the completion of the fit, the hermit crab is like a bud with a pink rose (the one with the tentacles). The tentacles sway with the water in the tank.

Of course, this is not over, this is just a shelling, and it has not been installed yet. It took about 12 hours to let the anemone climb up, and it took about 4 hours to fully adapt to the new host crab. Only then did it really "sign the contract" and succeed in fit.

Source after the fitting crab after fit: Akihiro Yoshikawa

After the completion of the fit, the hermit crab is like a pink flower bone, and the tentacles sometimes shrink to the buds to be released, and sometimes the expansion becomes Ksuru tentacles sway with the water.

Scientists add the photos of the photos and anemone for the sources of the filter to the photo: Akihiro Yoshikawa

Is it mutually beneficial or forced to cooperate?

It took so long to succeed. Do you say this? All of this is of course worthwhile, which is good for both parties. For home crabs, not only the new home is cool and rich in the atmosphere of Kosu, it looks very different from other ordinary home crabs.

The most important thing is that the new family anemone can secrete toxic substances, which is more lethal than the ordinary conch shell, which can prevent it from the harm of parasites and predators. For Cassifer's anemone, the fit is equivalent to having a mount, which can only be fixed in one place to filter -feed -oriented floating creatures.

Source of HPs full of tentacles: Akihiro Yoshikawa

However, is this mutually beneficial symbiosis that is not completely determined, it is just a speculation of scientists. Because Huanju crabs can survive without Casifa anemone, anemone is not a necessity for survival. In addition, the HPs unloaded the anemone and packed it on it. It also meant to be a little compulsive.

Picture source: Akihiro Yoshikawa

Having said that, it is not the first time that crab bullying anema. Lybia Tessellata, also known as boxing crab. This guy ’s favorite thing is to put a sunflower on your hand and use it as a toxic boxing glove as a weapon. Their relationship is not like mutual benefit, more like slavery ...

Boxing crab's toxic "boxing set" picture source: aquainfo

Picture source: aquainfo

In fact, the phenomenon of seaflowers attached to the versatile crabs is not the first time that it has been discovered. In addition to Cassifer's anemone, there are also non -Red Oceani (Adamsia), Calliactis (Calliactis), and Paracalliactis (Paracalliactis). This type of anemone can be installed on her home crabs. One of the important reasons that they can attach is that the abdomen will produce a few types called Carcinoecium with a few picenne substances that are admitted to the back of the versatile crab to complete the fit.

One of the important reasons that they can attach is that the abdomen will produce a few types called Carcinoecium with a few picenne substances that are admitted to the back of the versatile crab to complete the fit.

Picture source: Species New To Science

Picture source: Semantic Scholar

As for whether it is a real mutual benefit, there is no absolute answer. Perhaps the anemone is just under the fence. I want to survive but must "use" the status crab.

Produced: Popular Science China

Author: Su Chengyu

Producer: China Science Popularization Expo

Edit: Wang Tingting

references:

1. https://www.journals.uchicago.edu/doi/10.1086/719160

2. https://www.sciencedirect.com/science/article/abs/pii/s1055790310002083

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