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25 Delicious Facts About Lobsters

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We cracked open America's favorite crustacean, Homarus americanus, to plate the delicious facts hiding inside. Bob Bayer, head of the University of Maine’s Lobster Institute, helps us out.

1. If you cut a lobster, does it not bleed? Yes, of course—but it doesn't look like you'd expect. Lobster blood is colorless until exposed to oxygen, at which point it turns blue.

2. Typically, lobsters are a mottled brown, but genetic mutations can create red, blue, calico, and even albino lobsters. Heat denatures the proteins in the lobsters’ shells, releasing astaxanthin, which turns their shells bright red when they’re cooked.

3. Every time they molt—splitting their shells along the seam in the carapace—lobsters increase 20 percent in size. Young lobsters molt several times a year, but after they hit one pound, they start molting annually. After finding a soft place to hide, “they shed every part of the hard material, including the lining of the intestine,” Bayer says. "When the lobster comes out of its old shell, it’s all wrinkly. Its new shell is softer than your skin. If you take that lobster out of water, the claws will fall off; it doesn’t have the mechanical strength to keep the claws on." Then they eat their old shells for the calcium and phosphorus.

4. Freshly molted lobsters are called shedders.

5. The warmer the water, the faster lobsters grow.

6. Lobsters have three pairs of antennae, the largest of which is used for tactile sensing. "If a lobster’s going to go into a hole, for example, it’ll wave those large antennae around, sort of feel the hole, and then determine if it can fit, and then it’ll back in and hide," Bayer says. The two smaller pairs are chemosensory, helping the lobster find its food by sensing dissolved substances in the water, "a combination of our sense of taste and smell in one function,” according to Bayer.

7. The bigger claw is called the crusher claw, and lobsters use it to break up clams, crabs, and sea urchins. The cutter claw is used for tearing. “Some good-sized lobsters can raise a pressure closing strength of 100 pounds per square inch,” Bayer says. “Most of them are less than that, but it’s still a good amount of pressure.” If a lobster loses one of its claws or walking legs, the limb will regenerate. "If you’ve got a wound around the time that lobster is molting, you sort of get mixed biochemical signals, so you might end up with a duplicate of something," Bayer says. "You might get, say, two thumbs sticking out of the same claw."

8. Lobsters walk forward, but if they need to quickly get away, they propel themselves backward by pumping their tails. Females have broader tails than males so they can hold eggs there.

9. These crustaceans can’t see clear images, but their compound eyes are sensitive to light. Severing the eyestalk—which also serves as the lobster's hormonal center—will cause it to molt. And eyes don't grow back.

10. Lobsters use the front two legs—which are studded with chemosensory hairs—to put food into their mouths. “It almost looks like a squirrel eating,” Bayer says. The food goes into the stomach, where the gastric mill—made up of three teeth-like structures—grinds it up. Next, the food travels through the tomalley—a.k.a. the green thing you scrape off your meat. It’s the lobster’s main digestive tract: a small intestine, pancreas, and liver in one—and it’s a delicacy!

11. Lobsters aren’t scavengers; in fact, they feed on a large variety of live things, including other lobsters, marine worms, clams, mussels, and crabs in addition to bait (which is most often salted herring).

12. It takes a lot of herring to catch a lobster: "It averages about a pound of herring per pound of lobster that’s caught," Bayer says. "It’s expensive. It may be more than we need. We actually had a student who looked at this, and she found that you could use less and catch the same amount of lobster. But old habits die hard."

13. Fin-like structures called swimmerets help lobsters circulate water inside their shelters; females also use them to carry eggs.

14. Lobsters pee out of their faces. The urine comes from antennal glands located near the antennae. "They're greenish brown spots," Bayer says. "They actually look like two pieces of snot—that’s the best way to describe them. You'd have to open them up to see them." Peeing at each other is part of both fighting and courtship.

15. Speaking of courtship: In lobsters, it's kind of complicated. To woo a dominant male—who will have previously spent his time beating up her and all of the other lobsters in his neighborhood—the female heads to his shelter a number of times and pees pheromone-laced urine into it, which helps him relax. Because lobsters are cannibals, the pheromone is telling him two things: “It’s time to breed" and "Don’t eat me!” 

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Eventually, when he is sufficiently wooed, she'll move into his shelter and molt, at which point he uses the first pair of swimmerets—which, in males, are hard and bone-like and called gonopods—to transfer sperm to her. She'll stay in his shelter for another 10 days or so while her new shell hardens. Then she's back to her own life, and it's time for a new female to woo the male.

16. She stores the semen in a receptacle between her walking legs for six to nine months before she extrudes eggs, which then sit on her tail for another six to nine months. "When they’re immature, they’re very dark," Bayer says. "As they’re getting ready to hatch, these larvae, you can see the eyes." 

17. A lobster that's a pound and a half might carry 8000 to 10,000 eggs, which are kept in place by glue created in her cement glands. "The bigger they are, the more eggs they have," Bayer says. "You might have 30,000 or 40,000 on a really big lobster." If you’re eating lobster and find bright red stuff, that’s unextruded eggs—also known as roe.

18. When a fisherman traps a female lobster carrying eggs, he puts a V-notch in her tail. This tells other fishermen that she's a breeding female whether she has eggs or not, and should be thrown back. "They’re protected as long as that notch is present," Bayer says. "You're protecting your breeding population. If you think about it, it’s sensible, because you’re going to have your classes that don’t settle well, that don’t have good survival, but you’ve got this huge root stock that’s out there, so that the next year it can come back."

19. "When lobsters first hatch, they float—they float for the first couple of weeks," Bayer says. Some scientists call those floaters superlobsters, because they can swim forward in the water with their claws outstretched by beating the swimmerets under their tails. After this phase, they settle on the bottom. "Those that settle to the bottom, many of them will survive," Bayer says, "and it’s a good measure of what the upcoming stock is."

20. By the way: Despite what Phoebe from Friends believed, lobsters aren't monogamous. "Sometimes they'll have multiple parentage," Bayer says.

21. Fishermen used to guess at a lobster's age based on its size. Scientists only recently discovered an accurate way to determine a lobster's age: dissecting it and counting the rings in the eyestalk and gastric mill—similar to the way we calculate a tree's age.

22. The largest lobster ever recorded was caught near Nova Scotia in 1977 and weighed 44 pounds!

23. Science has shown that lobsters can recognize each other. Researchers at Woods Hole Oceanographic Institution set up an experiment where two crustaceans fought each other in a ring. Later, when they tried to have those same two lobsters fight again, the one that lost the first time recognized the winner and backed down immediately. "It wasn't just that the loser lobster had become a sissy or something," Trevor Corson, author of The Secret Life of Lobsters, told National Geographic. "When matched with a new lobster, he fought ferociously. So he was recognizing that previous lobster. They blindfolded him, and it didn't make a difference. So we get back to this pissing-in-each-other's-faces thing. [The scientists] catheterized a lobster with little tubes attached to its face and collected urine during combat. It turned out that without the urine in the water, the lobsters couldn't recognize each other." The losing lobster would recognize the winner for up to a week.

24. Can lobsters and other crustaceans feel pain? Scientists have gone back and forth on this; some recent research suggests that they probably do, while another study, published in 2005, says they don't. "There can be no absolute answer," Bayer says, though he's in the "no pain" camp. "They sense their environment, but don’t have the intellectual hardware to process pain. [If you look at] the nervous system of a lobster next to a grasshopper, and what’s notable is that the nervous system is so primitive that there isn’t really much to it. We argue that there is no brain and no ability to process pain. They do respond to their environment, and they sense that it’s not right for them. If they sense warmth or even chemicals in their environment, they’ll try to avoid them, those things that are noxious." Some suggest that the most humane way to cook a lobster is to start by putting it in fresh cold water or the freezer—both of which essentially puts it to sleep—before dropping it in the pot. (The "scream," by the way, isn't a scream at all, but steam escaping from their shells.)

25. According to Bayer, "Anything that kills insects can kill a lobster," and lobsters are extremely sensitive to insecticides, even at parts-per-billion concentration: "They’re so sensitive that, if you’ve got a room with a lobster tank, and you take an insecticide and you give it a five-second spray at the end of the room, it's likely that all those lobsters would be dead by the end of the day," he says. So we might want to think about what we're dumping into our oceans.

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Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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Opening Ceremony
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These $425 Jeans Can Turn Into Jorts
May 19, 2017
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Opening Ceremony

Modular clothing used to consist of something simple, like a reversible jacket. Today, it’s a $425 pair of detachable jeans.

Apparel retailer Opening Ceremony recently debuted a pair of “2 in 1 Y/Project” trousers that look fairly peculiar. The legs are held to the crotch by a pair of loops, creating a disjointed C-3PO effect. Undo the loops and you can now remove the legs entirely, leaving a pair of jean shorts in their wake. The result goes from this:

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Opening Ceremony

To this:

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Opening Ceremony

The company also offers a slightly different cut with button tabs in black for $460. If these aren’t audacious enough for you, the Y/Project line includes jumpsuits with removable legs and garter-equipped jeans.

[h/t Mashable]

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