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Meet This Bizarre and Mysterious Ribbon Worm

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Gorgonorhynchus repens discharges a sticky proboscis in response to a perceived threat. Rachel Koning, Wikimedia Commons // CC BY-SA 4.0

If you aren’t one of the 5 million people who’ve watched a 9-second video of a bizarre purple worm vomit a milky living tree all over a random man’s hand (perhaps in Thailand, judging from the YouTube titles), you should be. Watch it now.

(Editor's note: This post references a video that is no longer available. We've updated it with a similar video of a ribbon worm.)

Now that you're up to speed, you’re probably wondering what’s going on here.

To learn more, mental_floss spoke to biologist Sebastian Kvist, associate curator of invertebrates at the Royal Ontario Museum, where he specializes in Nemertea, the phylum of ribbon worms this creature belongs to.

That Milky Goo is Hunting Gear 

The upshot: This animal is weird, rare, and mysterious—even to scientists. The invertebrate is likely from the genus Gorgonorhyncus, which lives in shallow marine waters. That milky goo is actually the worm’s hunting gear: a very rare branching proboscis that this aggressive predator shoots out from a specialized port to net prey, including mollusks, snails, and even other sea worms. It then drags the captured prey into its mouth and swallows it whole.

The worm also throws out its proboscis as a defensive strategy—and that’s what we’re seeing in the video, Kvist says. The worm tries to defend itself by casting out the proboscis, which splatters against the man’s hand. And then the worm starts convulsing. That’s not good. “What we’re seeing is a very stressed worm that’s doing everything it can to try to get away from the situation that it’s in,” Kvist says.

It’s no wonder the worm dislikes the open air. With a soft body only a few millimeters wide, it has a hydrostatic skeleton, which means it relies on the ocean’s water pressure to keep its body in one piece. If you pick up a ribbon worm, its fragile body often simply falls apart. Amazingly, that doesn’t generally kill it. “We’re not sure if it’s able to regenerate or not, but it doesn’t seem to be fatal to the worm to break like that—which is really interesting,” Kvist says. Since the worm in the video seems to be in one piece, it’s possible that if it was returned to the water within 10 minutes—about as long as the ribbon worms Kvist has collected seem to tolerate being out of the water—it could have survived its trip to dry land.

How Old Are They? Good Question. 

What scientists don’t know about Gorgonorhyncus, and ribbon worms in general, turns out to be quite a lot. There are only a handful of species with a branched proboscis, and they don’t seem to be closely related. That suggests this rare anatomical trait arose independently several times. These few Gorgonorhynchus species live in Bermuda, and a cousin genus, Dendrorhynchus, has been spotted in China. None have been found in Thailand.

They’re also scarce. Even in Bermuda, where the marine environment has been extensively researched by scientists, these worms have only been discovered a handful of times.

We have no idea how old ribbon worms are either. Being soft bodied and boneless, ribbon worms leave virtually no trace in the fossil record. “That becomes a very problematic thing for trying to establish how recent or how ancient these guys are,” Kvist admits.

Kvist hopes his own research will help solve some of the mysteries surrounding ribbon worms. One focus is the phylogenetic affinities, or genetic relationships, among the 500 or so Heteronemertea ribbon worms, which have proboscis ports that are separate from their mouths—just like our viral video star Gorgonorhynchus does. Kvist is trying to figure out whether they share a common ancestor.

He’s not the only one studying them. A Harvard-run consortium of nemertean specialists called NemPhyl  are researching the evolution and genetics of these intriguing creatures. And there’s a lot to study. Gorgonorhynchus may be rare, but ribbon worms are found across the globe in marine, freshwater, and terrestrial environments. One is especially notable: Lineus longissimus, which has been measured at more than 30 meters long. “A lot of people think the blue whale is the largest animal in the world,” Kvist says. “Actually, a Nemertean is the longest animal in the world.” 

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
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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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Cs California, Wikimedia Commons // CC BY-SA 3.0
How Experts Say We Should Stop a 'Zombie' Infection: Kill It With Fire
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Cs California, Wikimedia Commons // CC BY-SA 3.0

Scientists are known for being pretty cautious people. But sometimes, even the most careful of us need to burn some things to the ground. Immunologists have proposed a plan to burn large swaths of parkland in an attempt to wipe out disease, as The New York Times reports. They described the problem in the journal Microbiology and Molecular Biology Reviews.

Chronic wasting disease (CWD) is a gruesome infection that’s been destroying deer and elk herds across North America. Like bovine spongiform encephalopathy (BSE, better known as mad cow disease) and Creutzfeldt-Jakob disease, CWD is caused by damaged, contagious little proteins called prions. Although it's been half a century since CWD was first discovered, scientists are still scratching their heads about how it works, how it spreads, and if, like BSE, it could someday infect humans.

Paper co-author Mark Zabel, of the Prion Research Center at Colorado State University, says animals with CWD fade away slowly at first, losing weight and starting to act kind of spacey. But "they’re not hard to pick out at the end stage," he told The New York Times. "They have a vacant stare, they have a stumbling gait, their heads are drooping, their ears are down, you can see thick saliva dripping from their mouths. It’s like a true zombie disease."

CWD has already been spotted in 24 U.S. states. Some herds are already 50 percent infected, and that number is only growing.

Prion illnesses often travel from one infected individual to another, but CWD’s expansion was so rapid that scientists began to suspect it had more than one way of finding new animals to attack.

Sure enough, it did. As it turns out, the CWD prion doesn’t go down with its host-animal ship. Infected animals shed the prion in their urine, feces, and drool. Long after the sick deer has died, others can still contract CWD from the leaves they eat and the grass in which they stand.

As if that’s not bad enough, CWD has another trick up its sleeve: spontaneous generation. That is, it doesn’t take much damage to twist a healthy prion into a zombifying pathogen. The illness just pops up.

There are some treatments, including immersing infected tissue in an ozone bath. But that won't help when the problem is literally smeared across the landscape. "You cannot treat half of the continental United States with ozone," Zabel said.

And so, to combat this many-pronged assault on our wildlife, Zabel and his colleagues are getting aggressive. They recommend a controlled burn of infected areas of national parks in Colorado and Arkansas—a pilot study to determine if fire will be enough.

"If you eliminate the plants that have prions on the surface, that would be a huge step forward," he said. "I really don’t think it’s that crazy."

[h/t The New York Times]