Irregular Times Diaries: Unfit Discussion

At first, I read the news from National Geographic about pilot whales with excitement. The article described a new scientific study as finding that pilot whales are the “cheetahs of the sea”, reaching surprising speeds in their deep water dives.

That surprising speed? 28.8 feet per second. That sounds fast, until I did the conversion into miles per hour: 19.6 miles per hour. Cheetahs are purported to go about 70 miles per hour. The pilot whale isn’t even close.

Yes, I know that water is much thicker than air. However, pilot whales could use advantages of underwater locomotion, such as buoyancy, that would more than compensate for that.

The underwater crustacean the mantis shrimp gets much closer to the cheetah, moving its smashing claw at a literally striking 51.1 miles per hour.

Think that doesn’t count, just because it’s the claw moving, and not the whole animal? Well then, I suggest you go out on a fishing vessel and pick up the first mantis shrimp they haul in with their nets. Go ahead and try to hold it in your hands, and then see what you think of its speed.

A while ago, I published an article explaining that mantis shrimp can be eaten, as much as many of us might like to see them alive.

I’ve always wonder how fishermen manage to get a commercially viable harvest of mantis shrimp, given the way that they can break bones or slash open flesh with their powerful front smashers or stabbers.

Out of curiosity, I’ve been looking for images of what mantis shrimp actually looks like when cooked and prepared as part of a meal.

I found a video that shows just that. If you’ve got stomatopod-loving kids in the household, cover their eyes.

I have to admit that I’m a bit confused about all the news articles talking about a “new” discovery about the eyes of mantis shrimp (stomatopods). The articles talk excitedly about the discovery that the eyes and brain of the mantis shrimp can perceive shifts in polarized light in meaningful ways.

I hate to put a damper on mantis shrimp research, but wasn’t this already known. Back in October, I wrote here, “The stomatopod’s cornea is bisected by a few rows of special sensors that detect color and polarized light.” That mantis shrimp use

Well, maybe this offers something new: “The researchers describe the anatomical basis for stomatopods’ remarkable vision in detail and show that these structures are stimulated when circular polarized light shines into them. They also offer behavioral proof of the stomatopods’ ability by training them to associate either left-handed or right-handed circular polarized light (L-CPL or R-CPL) with a food reward.”

Maybe the precise understanding of the anatomical structure in stomatopod eyes is new. Maybe. However, it was my impression that these things had also already been researched. I’d love to hear from some stomatopod experts out there to set me straight.

This has nothing to do with the mantis shrimp directly, but it does have to do with life in the sea, and so I thought I’d drop a little plug for it. A little plug… hmm. I’ll hold onto that for a second.

I was going to call this a little squid, and it does belong to the Decapodiformes, the group that includes squid and cuttlefish. However, this animal is not exactly a squid, and it isn’t a cuttlefish either. It’s a round squiggly dot known by the scientific name Stoloteuthis leucoptera. If we had to give its group of cephalopods a name, we might call them, scientifically, the sepiolids.

Scientific names lack something when it comes to the imagination, however. We don’t all spend time in wood-paneled lounges at the headquarters of the British Geographical Society.

So, I’d like to hear people’s ideas for a common name for this little animal. Personally, I’d like to see the genus it belongs to given the common name of “little plugs”. This one in particular might be called the stumpy plug.

You can find out more about this animal at the tree of life.

I have, in my brief discussions of mantis shrimps (known scientifically as stomatopods), discussed some rather extreme violent abilities, smashing and stabbing at the speed of a small bullet, that make them seem like rather fearsome creatures. There are some other attributes of mantis shrimps, however, that make them rather beautiful. Look into their eyes, and you will see what I mean.

Stomatopods have just two eyes, like you and me. However, unlike you and me, they are capable of performing acts of binocular vision with just one eye at a time. How is this accomplished, without two separate eyes providing slightly different images which can then be triangulated with the power of the brain?

The stomatopod’s cornea is bisected by a few rows of special sensors that detect color and polarized light. This means that one eye receives two different half signals. Furthermore, the sensory input from these two halves of the eye are processed by the nerves right at the eye itself, not at the brain. The result is that it’s not easy to sneak up on a mantis shrimp, which can rotate its eyes around independently of each other. Think of that - two separate binocular detection systems in opposite directions at the same time.

Far out… literally.

Stomatopods are often described as vicious creatures - for doing the same sort of things that human beings do, smashing and stabbing. Is there a tender side to the mantis shrimp, as well?

Yes, as a matter of fact, mantis shrimp do have a tender spot, under their invertebrate exoskeletons. There are some species of mantis shrimps that practice monogamy.

That’s no small feat for a mantis shrimp, because they tend to be very territorial animals, even in dealing with members of the opposite sex in their own species. Researchers have found that stomatopods need to find a way to selectively turn off their territoriality in order to pursue a more stable strategy for the continuation of the species. Is there a lesson for humans, that family values are strongest when the instinct to establish security over territory is overcome? I’ll leave the final decision to the political scientists, but there is some benefit to consider, I’m tempted to say, in the role of peaceful coexistence for the survival of the species.

Lest we take the anthropomorphic path too far, and declare mantis shrimps to be models of monogamous family values in a progressive sense of open territoriality, it’s important to remember that there are more species of mantis shrimps that are non-monogamous than that are monogamous. Most stomatopods love them and leave them, the better not to get bashed the morning after.

I referred to the amazing power of the front legs of the mantis shrimp a couple of days ago. Today, I’m bringing you something of an explanation of how it all works. It’s a video of Sheila Patek from UC Berkeley, giving a lecture on the mechanics of the stomatopod’s striking arms.

Ignore the annoying trailer at the front. From ants to architecture, and some amazing super slow motion video of the mantis shrimp’s attack, it’s all there:

Okay, folks, this is the mantis shrimp information that you’ve all been waiting for without knowing that you’ve been waiting for it. Prepare to run for the hills with your arms waving.

Mantis shrimp are the strongest animals on Earth. No kidding. Okay, a mantis shrimp is not able to exert as much energy as, say, an elephant. No way could a mantis shrimp knock down a tree… as fast as an elephant could.

So what? The elephant is big. Big is easy. Strong is not so easy.

The biggest mantis shrimp is as long as your forearm. However, a mantis shrimp can break through aquarium glass with one blow. How? It’s got a special pair of front legs that are spring loaded with such devastating power that they are as fast as a bullet fired by a small handgun.

A lot of people read that without considering the implications. The bullet fired by a small handgun is fired into the air, a relatively thin material. The mantis shrimp’s claws, on the other hand, have to move through water.

The mantis shrimp unleashes so much force on the objects it smashes that the hammer in its front leg produces a flash of light. You can see this effect in a small video of a stomatopod strike provided by the University of California at Berkeley. The video looks slow, but that’s because it’s displayed at 900 times slower than actual speed. That’s the only way you can actually see what a mantis shrimp attack looks like.

These animals frequent the Chesapeake Bay, among other places, and fishermen call them “thumb busters” because their blow is actually capable of shattering the bone in a human thumb. Dr. Roy Caldwell, the world’s top stomatopod researcher, says that he has seen a mantis shrimp knock the heads off of another mantis shrimp in one brutal blow.

Not all mantis shrimps are like this, of course. Others are slashers. Slasher mantis shrimps have sharp barbs on their front legs, that rip the target to shreds with almost as much power as the smashing blow.

For more on the science behind these attacks, read an excellent article from USA Today on mantis shrimps.

A couple of days ago, there was a little bit of a dispute, in response to my first mantis shrimp blog entry, about whether people eat mantis shrimp. It turns out that the Italians do indeed eat mantis shrimp. Here’s one recipe: Canocchie alla Pezza.

It will be noted, however, that this recipe does not call for the use of tawdry cocktail sauce. Instead, it suggests lemon, garlic, salt and olive oil. A much lighter taste.

For a better read, catch the same blogger’s visceral repulsion to the stomatopod, in her article entitled: The Horrible Mantis Shrimp. Fun fact from that article: A few mantis shrimp species have sufficient strength in their front claws to break through the glass of aquarium tanks, and scuttle around your home in fury for a while before dying.

Another blogger, Astron, refers to mantis shrimp meat as “tender and sweet”. Oh, the humanity!

It’s the second installment of this mantis shrimp blog today, and what a glorious morning it is to talk about stomatopods for me, Mantis Shrimp Man, the web’s preeminent stomatopodophile.

Stomatopod is the Latin name for mantis shrimp, and you may have caught yourself wondering what the heck stomatopod means in Latin. Obviously, pod means foot, but what about stoma? I remember from back in high school biology that leaves have stoma in them, pores to let moisture out. So, does stomatopod mean porous foot? Almost. It means mouth foot.

Does that mean that these mantis shrimp actually have mouths in their feet, with little teeth and stuff? While that would be very interesting, no. The choice of the Latin name mouth foot was chosen because their anatomy revolves around an interesting front pair of feet that are used to capture food and bring it to their mouths.

I’ll be talking about that pair of feet quite a bit in the future, because they’re just fascinating. Be patient. In the meantime, read a short article from Duke Magazine on the subject.

World, you shall now celebrate, for lo, the mantis shrimp blogging has begun. My name is Mantis Shrimp Man, and I have requested and received from Irregular Times an Irregular Diary account, and a category within the Irregular Diaries that is devoted to mantis shrimps. That makes my category within the Irregular Diaries the world’s one and only mantis shrimp blog.

Tonight, I introduce the concept of the mantis shrimp to you through the scientific name of the mantis shrimp: Stomatopod

Stomatopod is a bit of a difficult word to remember until you break it down. It’s the word tomato with an S on the beginning, with a POD on the end. The way I think about it is that a stomatopod is like an iPod, except that it’s a tomato with a lisp. It’s an absurd enough idea to stick in my mind.

Is an iPodish tomato with a lisp really a good description for a mantis shrimp? Well, that’s what this mantis shrimp blog is really all about… sort of. Once you explore the fascinating life of the mantis shrimp deeply enough, however, you should be able to answer that question.