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10 Fanged Facts About Heterodontosaurus

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Wikimedia Commons

Heterodontosaurus was a weird little animal—one that has been surprising scientists since its discovery in 1962. Prepare to be perplexed.

1. Its Dentition Was Complicated (By Reptile Standards).

Imagine having a mouth filled with nothing but bicuspids. If you’re reading this sentence, we’re assuming you’re a mammal. And, like most mammals, your mouth contains several types of teeth. Reptiles, in contrast, have more uniform jaws. To them, one tooth variety per species is considered normal.

Yet Heterodontosaurus sported small peg-like teeth, enlarged canines (colloquially referred to as “tusks”), and a row of squarish shearing chompers. For those keeping score, that’s three very different-looking types. The neighbors must have been jealous…

2. Heterodontosaurus’ Hands Were Great at Grasping.

On each hand, Heterodontosaurus had five fingers, two of which were opposable. These doubtlessly made mealtimes a little bit easier.

3. It Had a Fairly Flexible Tail.

Many of Heterodontosaurus’ relatives featured something this turkey-sized dino lacked: long, bony tail tendons which, while stabilizing, arrested a certain degree of mobility. 

4. Heterodontosaurus Resided in Modern-Day South Africa.

You’ll have to visit Capetown, home of the Iziko South African Museum, to see the world’s best Heterodontosaurus specimens. For those interested, ostrich-like Nqwebasaurus and the long-necked Massospondylus also rank among this nation’s dinosaurs.

5. Those Frightening “Tusks” Could’ve Been Handy Digging Tools.

Perhaps Heterodontosaurus sifted through topsoil with its blade-like canines, scrounging for roots and other buried treasures. Maybe they were used to break into termite mounds or scare off would-be predators. We may never learn the “tooth” of the matter.

6. It Turns Out that Youngsters Had Tusks, Too.

The first known baby Heterodontosaurus skull was finally identified in 2008. Less than two inches long, this teeny, tiny fossil would’ve been dwarfed by a household teabag. According to paleontologist Richard Butler, the specimen “had relatively large eyes and a short snout when compared to an adult—similar to the differences we see between puppies and fully grown dogs.” And there was more. Some had previously argued that, as with modern warthogs, Heterodontosaurus’ tusks didn’t come in until after the critter reached maturity. Yet this little tyke proudly displayed a pair of those iconic canines, disproving that idea.

7. Heterodontosaurus Might’ve Been an Omnivore.

Heterodontosaurus is traditionally cited as an herbivore. But did the wee creature also gobble up insects or the occasional vertebrate from time to time? It’s entirely possible. After all, true herbivory is actually quite rare in today’s animal kingdom; even supposedly strict vegetarians like farm cows have been caught munching on live prey.

8. One of its Cousins Was Covered in Bristles.

Tianyulong of China had long, hollow, feather-like fibers all over its body. Though Heterodontosaurus died out approximately 60 million years earlier (during the early Jurassic period), the beastie may have had similar structures to those of its Asian relative.

9. Heterodontosaurus’ Family Has Huge Implications for the Origin of Feathers

We’ve known for decades that many non-avian dinosaurs had feathers. But evidence of plumage usually shows up within a very specific group, namely theropods—or “meat-eating” dinos—such as Velociraptor. However, Tianyulong and other heterodontosaurids were ornithopods, a clan which represents a very different branch of the dinosaurian family tree. Because such distantly-related animals have been found with somewhat similar coverings, it seems likely that feathers started evolving at a very early point in dinosaur history. 

10. The University of Chicago Recently Built an Amazing Heterodontosaurus Bust.

This behind-the-scenes video should be required viewing for anyone interested in the marriage of art and science. For this masterpiece, sculptor and fossil preparator Tyler Keillor won the 2012 Lanzendorf Paleoart Prize. 

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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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200 Health Experts Call for Ban on Two Antibacterial Chemicals
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In September 2016, the U.S. Food and Drug Administration (FDA) issued a ban on antibacterial soap and body wash. But a large collective of scientists and medical professionals says the agency should have done more to stop the spread of harmful chemicals into our bodies and environment, most notably the antimicrobials triclosan and triclocarban. They published their recommendations in the journal Environmental Health Perspectives.

The 2016 report from the FDA concluded that 19 of the most commonly used antimicrobial ingredients are no more effective than ordinary soap and water, and forbade their use in soap and body wash.

"Customers may think added antimicrobials are a way to reduce infections, but in most products there is no evidence that they do," Ted Schettler, science director of the Science and Environmental Health Network, said in a statement.

Studies have shown that these chemicals may actually do more harm than good. They don't keep us from getting sick, but they can contribute to the development of antibiotic-resistant bacteria, also known as superbugs. Triclosan and triclocarban can also damage our hormones and immune systems.

And while they may no longer be appearing on our bathroom sinks or shower shelves, they're still all around us. They've leached into the environment from years of use. They're also still being added to a staggering array of consumer products, as companies create "antibacterial" clothing, toys, yoga mats, paint, food storage containers, electronics, doorknobs, and countertops.

The authors of the new consensus statement say it's time for that to stop.

"We must develop better alternatives and prevent unneeded exposures to antimicrobial chemicals," Rolf Haden of the University of Arizona said in the statement. Haden researches where mass-produced chemicals wind up in the environment.

The statement notes that many manufacturers have simply replaced the banned chemicals with others. "I was happy that the FDA finally acted to remove these chemicals from soaps," said Arlene Blum, executive director of the Green Science Policy Institute. "But I was dismayed to discover at my local drugstore that most products now contain substitutes that may be worse."

Blum, Haden, Schettler, and their colleagues "urge scientists, governments, chemical and product manufacturers, purchasing organizations, retailers, and consumers" to avoid antimicrobial chemicals outside of medical settings. "Where antimicrobials are necessary," they write, we should "use safer alternatives that are not persistent and pose no risk to humans or ecosystems."

They recommend that manufacturers label any products containing antimicrobial chemicals so that consumers can avoid them, and they call for further research into the impacts of these compounds on us and our planet.