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Tongue Length and Other Things You Should Know About Giraffes

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The proud papa isn’t able to pass out cigars, but there was still plenty of celebrating at the Cincinnati Zoo, where earlier this month a giraffe has been born for the first time in 26 years. Tessa, a four-year-old Maasai giraffe, delivered the calf at 9:40am on April 2, and 20 minutes later the tyke (who was later identified as a female, and whose name “Zuri" was selected via a Facebook contest) was tentatively balancing on her wobbly legs and nursing. Birthing a six-foot-tall baby with four sharp hooves sounds unbearably painful to any human who has demanded morphine seconds after her water has broken, but it’s just one of many inconveniences the world’s tallest animal has adapted to over the centuries.

Spot the Difference

Without access to the animal’s DNA, the second-best way to identify different types of giraffes is via the distinctive markings on their coats. There are nine recognized sub-species of giraffe, and for the most part each group keeps to themselves in specific geographic regions of Africa. However, Kenya has the unique distinction of being the only country that is home to three giraffe species – the Masai, the Reticulated and the Rothschild. Masai giraffes (left below) have irregular brown patches with jagged edges on a cream-colored background. Their Reticulated cousins (center) boast very clearly defined orangey-brown patches separated by bold white lines. And the Rothschild family (right) sports light, irregular patches (those less jagged than those of the Masai) on a white-to-buff background, with no markings below the knees.

Nature’s Support Hose

The giraffe is the world’s tallest animal, and as a result requires a lot of extra help to pump the blood all the way to its head. Their extra-large hearts weigh about 25 lbs. and pump fast enough to keep their central arterial blood pressure at 250 mmHg (compared to 100 mmHg in humans). Under normal conditions, that would result in a pressure of 400 mmHg in the legs (in simple terms: severely swollen ankles), but the giraffe has a secret weapon - the skin on its legs is extra thick and extremely tight-fitting, and it prevents the blood vessels from expanding and the blood from pooling. As they walk, their leg muscles help to vigorously pump the blood back upwards to the rest of the body.

In case you’ve wondered why giraffes don’t pass out from the head rush when they bend their heads down to drink, it’s because of the rete mirabile – a complex web of arteries, veins and valves that carefully regulate the blood flow to their noggins.

Gene Simmons Would Be Envious

The average giraffe’s tongue measures from 18 to 20 inches long. It’s also a blue-ish/purply color, but that’s not important right now. Despite the length of its neck, sometimes the tastiest acacia leaves (a staple of the giraffe diet) grow on the uppermost branches of the tree, so the giraffe needs those extra inches its prehensile tongue provides to reach up and grab those tender leaves, which provide not only nutrition but also much-needed moisture. The giraffe’s only natural predator is the lion, and the giraffe is most vulnerable to a lion ambush when it assumes the very awkward spread-legged position necessary to drink water from ground level. Eat enough moist acacia leaves and trips to the local watering hole are reduced proportionately.

Speaking of Tongues

[Image credit: Flickr user William Warby]

Some scientists postulate that the reason a giraffe’s tongue is a darkish color is to prevent sunburn, since it spends a large portion of the day outside of the animal’s mouth and exposed to the hot rays of the African sun. But evolutionary theories aside, scientists do agree that not only is the giraffe’s tongue extraordinarily “tough” – that is, it sustains surprisingly few cuts from the thorns found on acacia branches – it is also protected from infection from the few abrasions it does sustain by some very thick, very antiseptic saliva. That same saliva coats the thorns so thoroughly that they exit the animal in their original form, with no harm done to the digestive tract. Giraffes also capitalize on the antiseptic and prehensile qualities of their tongues by using them to (yech!) routinely clean their ears.

Up Close and Personal

Can an 18 foot tall animal equipped with a lethal kick be considered “cuddly”? Ask anyone who has stayed at Kenya’s Giraffe Manor, a small hotel located just outside of Nairobi. The Manor was originally constructed in 1932 as a hunting lodge by an heir to the Mackintosh Toffee fortune. The property was sold to Betty Leslie-Melville and her husband in 1974, and shortly after their purchase the Leslie-Melvilles found out that the few remaining Rothschild giraffes were in danger of being exterminated thanks to the sale of the animals’ sole habitat by the Kenyan government to a private real estate company. The Leslie-Melvilles, who already had three Rothschild giraffes roaming on their property, agreed to “adopt” two other giraffes who were slated for slaughter. In 1983 the family refurbished the lodge and re-opened it as a hotel. Since that time Giraffe Manor has worked with several wildlife groups in the breeding of Rothschild giraffes and re-introducing them into the wild to expand the gene pool. They fund their efforts via the hotel guests who willingly share their breakfasts with the Manor’s giraffes who quickly learned the meal schedule and are always sure to stick their necks in through a window to beg a tidbit.

Giraffe Manor is still operating today in case you’re ever in the vicinity; some of the celebrities who’ve noshed with the long-necked over the years include Johnny Carson, Mick Jagger, Brooke Shields and Walter Cronkite.

Life is Harsh: Lesson One

Giraffe birth appears to the human eye to be somewhat abrupt and austere. The reality of the situation does seem rather brutal: Mama’s hind legs are about seven feet tall. She does not lie down and curl up when those first contractions hit, but rather she stays upright and expels the baby from a standing position. Luckily, in the giraffe’s natural habitat, there is a ground covering of sand and some random flora to cushion baby’s first free-fall. In captivity, zoologists prepare a cushy sand bed when a cow (female giraffe) is ready to deliver. No matter what the locale, baby G’s introduction to the world comes as a rude awakening – a head-first PLOP onto the ground followed by a sharp hoof to the belly from Mama to stimulate movement. Even in the protective confines of a zoo or wildlife preserve, Nature still prods the mother giraffe to get her baby on its feet as soon as possible, lest there be predators nearby. Here's a graphic illustration of the giraffe birth process (but be forewarned that it is bodily fluid-intensive):

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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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Live Smarter
Working Nights Could Keep Your Body from Healing
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The world we know today relies on millions of people getting up at sundown to go put in a shift on the highway, at the factory, or in the hospital. But the human body was not designed for nocturnal living. Scientists writing in the journal Occupational & Environmental Medicine say working nights could even prevent our bodies from healing damaged DNA.

It’s not as though anybody’s arguing that working in the dark and sleeping during the day is good for us. Previous studies have linked night work and rotating shifts to increased risks for heart disease, diabetes, weight gain, and car accidents. In 2007, the World Health Organization declared night work “probably or possibly carcinogenic.”

So while we know that flipping our natural sleep/wake schedule on its head can be harmful, we don’t completely know why. Some scientists, including the authors of the current paper, think hormones have something to do with it. They’ve been exploring the physiological effects of shift work on the body for years.

For one previous study, they measured workers’ levels of 8-OH-dG, which is a chemical byproduct of the DNA repair process. (All day long, we bruise and ding our DNA. At night, it should fix itself.) They found that people who slept at night had higher levels of 8-OH-dG in their urine than day sleepers, which suggests that their bodies were healing more damage.

The researchers wondered if the differing 8-OH-dG levels could be somehow related to the hormone melatonin, which helps regulate our body clocks. They went back to the archived urine from the first study and identified 50 workers whose melatonin levels differed drastically between night-sleeping and day-sleeping days. They then tested those workers’ samples for 8-OH-dG.

The difference between the two sleeping periods was dramatic. During sleep on the day before working a night shift, workers produced only 20 percent as much 8-OH-dG as they did when sleeping at night.

"This likely reflects a reduced capacity to repair oxidative DNA damage due to insufficient levels of melatonin,” the authors write, “and may result in cells harbouring higher levels of DNA damage."

DNA damage is considered one of the most fundamental causes of cancer.

Lead author Parveen Bhatti says it’s possible that taking melatonin supplements could help, but it’s still too soon to tell. This was a very small study, the participants were all white, and the researchers didn't control for lifestyle-related variables like what the workers ate.

“In the meantime,” Bhatti told Mental Floss, “shift workers should remain vigilant about following current health guidelines, such as not smoking, eating a balanced diet and getting plenty of sleep and exercise.”