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Japanese Spider Crabs Why Not

Just claws

When I go to esports events I spend a lot of time in arenas and darkened studios focusing on screens and on digital worlds. Matches run long, interviews and transcriptions pepper the day and free time ends up being extra writing time. I want to attend the tournaments, don't get me wrong, but sometimes you get home and realise you saw nothing of an entire city even though you were there a whole week.

That is why I ended up at the Georgia Aquarium yesterday. I'd paid my dues to the gods of Smite, wrapped up all my Paladins interviews and had hours to kill between checking out and my home flight*. The Japanese Spider Crabs caught my attention. They're so alien and beautiful, living on the seabeds of the Pacific Ocean around Japan. I've been reading up about them. Here are some things I found out:

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1. Eavesdropping on a kid's conversation with aquarium staff I found out that the staff have to put protective boxes around the crabs sometimes. It's because of how they shed. When crabs grow their rigid exoskeleton can't expand to accommodate the bigger crab. Instead it must shed its old shell and grow a new one.

I found an account of how shedding actually works over on the National Oceanic and Atmospheric Administration website. The crab reabsorbs some of the calcium carbonate from its old shell before enzymes separate the old shell from the underlying skin. The skin then secretes a new soft shell beneath the old hard one.

"A day before molting, the crab starts to absorb seawater, and begins to swell up like a balloon. This helps to expand the old shell and causes it to come apart at a special seam that runs around the body. The carapace then opens up like a lid. The crab extracts itself from its old shell by pushing and compressing all of its appendages repeatedly. First it backs out, then pulls out its hind legs, then its front legs, and finally comes completely out of the old shell. This process takes about 15 minutes."

The new shell doesn't harden for a few days and so the crab is vulnerable. In the wild it is vulnerable to predators but in the tank at the Georgia Aquarium the crab is vulnerable to the other crabs in the tank who can be kind of jerks and poke their tank-mate with their long legs. The box is thus to protect the soft shell from jerks until it stiffens up.

2. The guy at the tank said the crabs can grow to 12 feet across because of their ridiculous supermodel legspan. That is a lot of crab.

The Blackpool Sealife centre apparently houses the world's biggest crab - a giant Japanese Spider Crab called Big Daddy. There is a professional Dota 2 player called BigDaddy. You can tell the two apart because one is a crab and the other is not a crab. Also the crab is 10.2 feet across. I think BigDaddy is like 5 something.

3. This is about crabs more generally but I learned that the name for the claw legs at the front of the crab is "cheliped". The claws themselves are also known as chelae so the legs that join them up to the crab are the chelipeds.

4. According to the Georgia Aquarium website:

"This species belongs to the Majidae family, which is known 'decorator crabs.' This group of crabs will pick up small anemones, pieces of sponge or other benthic animals and cement them to the top of their carapace (shell). This provides the crab with natural camouflage that protects it from predators."

I feel like this is a strong look which I want to embrace for 2016. I am not sure how I would best disguise myself at esports events though because sponges and anemones and benthic animals (they're the ones you find on or in the bottom of a body of water) would probably make me stand out. I mean I guess I could wear jeans and a hoody but I like the idea of just having things placed on my carapace - keyboard keys, cans of Red Bull, light-up dongers and USB sticks full of art assets and press info.

And that is my presentation on Japanese Spider Crabs. The end.

*It was that or I made good on my mission to track down an actual real peach tree rather than a street sign proclaiming Peachtree Boulevard or Parkway or Street. I don't know what a peach tree looks like if it doesn't have peaches dangling off it so it's probably just as well that I opted for the fish.

This article was originally published as part of, and thanks to, the RPS Supporter Program.

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About the Author

Philippa Warr

Former Staff Writer

Pip wrote for Rock Paper Shotgun between 2014-2017, covering everything from MOBAs, hero brawlers and indie curios. She also had a keen interest in the artistry of video game creation, and was very partial to keeping us informed of the latest developments in British TV show Casualty.