It Takes One Penguin to Break Up a Huddle

In nature documentaries, the huddles performed by penguins are often portrayed as astonishing acts of cooperation. And while watching thousands of penguins rotate through a crowd is impressive, this behavior doesn’t always end so gracefully once the camera cuts away.

During the 2005, 2006, and 2008 breeding seasons, André Ancel of the University of Strasbourg in France and his colleagues studied about 3000 breeding pairs of the emperor penguin colony of Antarctica’s Pointe Géologie Archipelago. In the December issue of Animal Behavior, the researchers report that the huddles they observed are much more complicated than they appear. The arrangements lasted a few hours at the most, and all it took was one penguin to break up the group in less than two minutes. 

In penguin huddles, the birds in the center are always depicted as having the sweetest set-ups while it's the ones around the perimeter that are thought to be taking one for the team. But when penguins decide to give up their prime interior spot, it's not necessarily out of altruism. The heat-conserving strategy works so well that the center of a huddle can reach temperatures of nearly 100°F, which is well past the point of comfort for penguins. Penguins shift towards the outside of the group not just to give other penguins a chance to get in, but because they're looking for some relief for themselves. After leaving a huddle, Ancel and his team observed some penguins eating snow, possibly as a way to cool down.

It was for this reason that the team of researchers hypothesized that most huddle breakups would begin at the center, but they only observed this happening once. Most of the time it was started by penguins on the exterior, and within two minutes of departure the huddle would be complete broken up. The huddles lasted anywhere from a dozen minutes to several hours, but the average length was 50 minutes. After they dispersed, a haze of warm air could sometimes be seen rising over the colony. The researchers think that while huddles begin as a way to conserve heat, the sudden breakups help to dissipate it. Consider that the next time you're watching footage of a penguin huddle—you should probably save some sympathy for the guys in the middle. 

[h/t: Science News]

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iStock // Ekaterina Minaeva
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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Name the Author Based on the Character
May 23, 2017
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