Author: Kate Horowitz

The same technology used to nab criminals may help keep endangered lemurs roaming free. The new LemurFaceID program, described this week in the journal BMC Zoology, offers a non-invasive way for scientists to track individual lemurs in the wild.

We can’t protect endangered species unless we understand their lives, co-author Stacey Tecot of the University of Arizona said in a statement. “Studying lemur individuals and populations over long periods of time provides crucial data on how long individuals live in the wild, how frequently they reproduce, as well as rates of infant and juvenile mortality and ultimately population growth and decline.”

But figuring these things out can be tricky for researchers and stressful for wild animals, who don’t particularly enjoy being caught and tagged, collared, or swabbed.

So conservationists have begun exploring more hands-off techniques, including facial-recognition software. Software developers have already applied the technology to African lions and right whales with some success. Biometrics expert and co-author Anil Jain of Michigan State University suspected it might work even better with lemurs, whose facial features are as varied as those of human beings.

To start, Jain and his colleagues compiled 462 images of 80 different red-bellied lemurs* from Madagascar’s Ranomafana National Park and the Duke Lemur Center in North Carolina, as well as 190 images of other lemur species. They standardized the photo formats, then created a program that would measure the proportions and features of the lemurs’ faces, thus devising a unique visual profile of each individual.

Initial tests of the LemurFaceID program were astoundingly successful, quickly matching an image to the right lemur with 98.7 percent accuracy. The researchers believe the software could be easily adapted to identify other primates, bears, red pandas, raccoons, and sloths.

“Facial recognition technology has the potential to help safeguard our society,” Jain said. “Adapting it to help save endangered species is one of its most inspiring uses.”

*One of the lemurs is named Avery. That’s not important to this story, but we thought you’d want to know.

Archaeologists at the University of Hawaii West Oahu have begun unearthing a long-forgotten relic from a dark period of American history.

The Honouliuli internment and POW camp was open for three years. In that time it saw the detention of more than 1000 Japanese-American citizens and thousands of prisoners of war.

UH archaeologist William Belcher is leading the excavations. He says that after the camp was bulldozed in 1946, it seemed to vanish from public consciousness. “When I was in elementary school, I never even heard that this had occurred,” he told NBC News. “We never studied this in history or talked about it.”

Thanks in part to former President Obama, that’s beginning to change. Obama, who was born and raised in Hawaii, designated the camp a national monument in 2015. Now Belcher and his students are digging in to help clear the site of seven decades’ worth of earth, grass, shrubs, and debris.

It’s a difficult task made even harder by the landscape. The camp is hidden inside a steep gulch that Japanese-American internees called “Jigoku Dani,” or “Hell Valley.” It’s unreachable by public roads and gets very, very hot during the day. Belcher and his students are clearing the site with machetes. “The basic technology is to walk in a systematic fashion across the entire landscape,” he told NBC News.

The internment situation during World War II looked different in Hawaii than it did in California or Washington state. Forty percent of Hawaiian citizens were of Japanese ancestry, and many of them were plantation workers. To protect the islands’ plantation economy, the government decided to confine some, but not all, citizens within the camp’s crowded enclosures and barbed-wire fences.

In naming the site a national monument, Senator Mazie Hirono told NBC News she hoped that recognizing our country’s troubled history might prevent us from committing similar atrocities in the future.

“The stories of those detained at Honouliuli and internment sites like it across the country are sobering reminders of how even leaders of the greatest nation on Earth can succumb to fear and mistrust and perpetuate great injustice,” Hirono said.

Scientists say the turbulent waters of the lower Congo River divided one fish family so thoroughly that it split into several different species. The researchers published their findings in the journal Molecular Ecology.

One 200-mile stretch of the river has a peculiar claim to fame—it’s become a sort of evolutionary playground, boasting more than 300 different species of fish alone. “In this very short section of the Congo, we find a tremendous diversity of fishes,” co-author Melanie Stiassny of the American Museum of Natural History said in a statement.

At a mere 3 to 5 million years old, Stiassny said, this segment of the river is still relatively young. “So what is it about this system that makes it such a pump for species?”

New species are formed when an existing species is split into two populations, often by some sort of insurmountable physical barrier. Over thousands of years, the different environments and pressures faced by the two populations will be so different that they’ll evolve into two separate species.

But there are currently no major dams in this section of the Congo, nor does the river branch or trickle off into lakes. The fish are all essentially swimming in the same body of water.

Stiassny and her colleagues had a theory: The behavior of the water itself had broken fish families apart. To test their hypothesis, they collected 53 fish, all members of the genus Teleogramma, from different sections of the strange 200-mile stretch. The researchers sequenced the fishes’ DNA and compared their bodies, looking for similarities and differences.

There were plenty of differences. Within those 53 fish the researchers had representatives of all five Teleogramma species [PDF]. But some of those species were practically living on top of one another—sometimes less than a mile apart. But there was always something between them: roiling river rapids.

Lead author Elizabeth Alter, of CUNY York College and AMNH, said the rapids are working the same way a wall or a mountain might, keeping the fish populations separate. “What’s particularly unique about the lower Congo is that this diversification is happening over extremely small spatial scales,” she said in the statement. “There is no other river like it.”

The fish may be facing even greater barriers in the near future, as the region has been proposed as the site of a new dam—a situation that Stiassny says would “majorly disrupt” this extraordinary ecosystem.

British scientists say startled honeybees emit a teeny “whoop!” noise when jostled or head-butted by another bee. The team described their findings this week in the journal PLOS One.

Bee societies are astoundingly sophisticated and complex; they’re strict hierarchies in which every bee knows its job and its place. To keep this social machine humming along, bees rely on multiple forms of communication: chemical signaling, electrical impulses, gestures (like their waggle dance), and sound.

One of the most common sounds is a quick little wing-buzz used often in crowded colonies. Bees seem to make this noise when they ask another bee for food and as they interfere with another bee’s waggle dance—a move that tells the second bee to change its plans. Because the buzz seemed to be used to abort the waggle dance and any foraging that might follow, scientists called the noise the “stop” signal.

To learn more about the signal, researchers at the UK’s Nottingham Trent University set up accelerometers and cameras inside honeybee hives and left them there for a year. (This particular sound is inaudible to the naked human ear and can only be picked up with monitoring devices.)

The resulting recordings were surprisingly packed with these little buzzes. So packed, in fact, that lead author Martin Bencsik began to suspect we’d misinterpreted its meaning. “There’s no way a bee was trying to inhibit another one that frequently,” he told New Scientist, “and there’s no way a bee would request food that frequently.”

So what is the buzz about?

Surprise, it seems. Video footage from inside the hives showed that bees mostly emitted that little sound after another bee had knocked into them, the same way you might say “whoa!” when a stranger suddenly jostles you on a crowded sidewalk. Bencsik and his colleagues propose that instead of calling the noise a “stop” signal, we should call it a little “whoop” instead.

The authors suggest that bees, like people, may complain more when times are hard—which means that we might be able to use the frequency of their little whoops to calculate their colony’s stress level.

The findings are “awe-inspiring,” entomologist and educator Gwen Pearson tells mental_floss. “Honeybees [were] domesticated centuries ago, but we are still trying to understand how they work.”

Our complicated relationship with the rainforest may be much older than we thought. Archaeologists writing in the Proceedings of the National Academy of Sciences say the creators of ancient South American earthworks had also been farming and clearing the Amazon for millennia before Europeans arrived. The most striking evidence for this manipulation of the landscape? Hundreds of geoglyphs discovered across the region, revealed by deforestation.

For a long time, the rainforest appeared lush and undisturbed, and we assumed it had always been that way. Then during the last century, cattle ranchers began cutting down more and more trees to make room for their livestock. When the sawdust had settled, massive shapes could be seen carved into the soil. Archaeologists discovered more than 450 of the geoglyphs in Brazil’s Acre State alone.

Lead author Jennifer Watling is an archaeologist at the University São Paulo. She said the glyphs’ discovery created quite a stir. “A lot of people have the idea that the Amazon forests are pristine forests,” she told The New York Times, “never touched by humans, and that’s obviously not the case.”

What was the case, then? To find out, Watling and her colleagues collected soil samples from two of the glyph sites. They sifted through the soil, picking out microscopic plant fossils and pieces of charcoal, then used carbon dating to approximate the age of each tiny bit of evidence.

They’ve been working on this research for a while; in the multilingual video below, from 2013, listen to the researchers explain some of their techniques.
 

 
The evidence told a story about the people who lived and worked in the forest around 4000 years ago. They had done some forest clearing of their own, burning sections of bamboo to open up space for farming. They likely grew maize or squash and collected food-bearing trees in one spot to create what Watling called a “prehistoric supermarket.” Once these forest farms were established, they began digging out the glyphs, which were likely used in religious rituals.

Unlike today’s industrial logging and clearing, the glyph-builders’ agriculture was sustainable in nature. Their farms and burn areas were small and contained, and permitted the surrounding wilderness and trees to keep on growing.

“Indigenous communities have actually transformed the ecosystem over a very long time,” said Watling. “The modern forest owes its biodiversity to the agroforestry practices that were happening during the time of the geoglyph builders.”

It seems nowhere on Earth is safe from the creeping, deadly fingers of pollution. Scientists analyzing deep-sea crustaceans found traces of manmade chemicals in the animals’ bodies. The researchers published their findings in the journal Nature Ecology & Evolution.

Amphipods, like the one shown above, are small, eyeless crustaceans that make their homes in the deepest, darkest parts of the ocean. The key to the deepwater amphipod’s survival is its stomach; it is both notoriously unfussy about what it eats, and gifted with special enzymes that help it digest just about anything, including plastic, animal carcasses, and even sunken ships.

But the oceans are a risky place to dine these days. Scientists have found dangerous chemicals, fibers, and pieces of plastic in the bodies of seabirds, mammals, mollusks, and fish alike.

The question for oceanographer Alan Jamieson and his colleagues was simple: How far down do these pollutants go?

To find out, they used deep-sea landers to collect three species of amphipods from the Mariana and Kermadec Trenches in the Pacific Ocean. They brought the animals back to the lab and tested their fatty tissue, looking for traces of 14 different pollutants.

And there they were. High levels of pollutants, including flame retardant chemicals, were found in every sample from every species, regardless of the depth at which the sample was collected. The contamination was so bad, it was comparable to that found in Japan’s Suruga Bay, long known for its high level of industrial pollution.

The authors say the chemicals most likely reached the trenches while clinging to pieces of plastic garbage or the bodies of dead animals from closer to the surface.

Biologist Katherine Dafforn of the University of New South Wales weighed in on the research in an accompanying editorial. She concludes that “Jamieson et al. have provided clear evidence that the deep ocean, rather than being remote, is highly connected to surface waters and has been exposed to significant concentrations of human-made pollutants.”

 
Astronomers at the University of Texas and the Space Telescope Science Institute have devised a way to clear visual noise from satellite images, revealing a glimpse of our universe in its infancy. They shared their findings on the preprint server arXiv.

The current hypothesis about our universe’s early days goes something like this: In the beginning, there was the Big Bang, with all its attendant spark and electrical charge. Some time after that, all went dark. Then the first galaxies bloomed, bringing with them clouds of energy that re-ionized and lit up the sky. Lovely as this story sounds, it’s been difficult to prove, as these old, old, old galaxies have long since grown pale and indistinct amidst the bright chaos of newer celestial goings-on.

Lead author Rachael C. Livermore and her colleagues figured that if they could dim or shut out some of that newer radiance, they might stand a chance of finding the ancient galaxies.

Their solution: a technique called wavelet decomposition, which can mask high-volume brightness the same way noise-canceling headphones shut out sound.

“The wavelet transform allows us to decompose an image into its components on different physical scales,” the authors wrote. “Thus, we can isolate structures on large scales … and remove them, allowing objects on smaller scales to be identified more easily.”

They applied this new method to Hubble telescope images of star clusters Abell 2744 and MACS 0416. And it worked like a charm. Selectively turning down the brightness revealed 167 never-before-seen galaxies, all quite elderly and faint.

The authors say their discovery provides “strong support” for the theory of re-ionization. They and other astronomers will have boatloads of new images to examine quite soon, as the James Webb Space Telescope is scheduled to launch in 2018.

Our oceans are an endless cornucopia of weirdness. Today, we’d like to introduce you to a cockeyed deep-sea cephalopod called the strawberry squid. Researchers writing in the journal Philosophical Transactions of the Royal Society B say each of the squid’s unusual eyes serves a separate purpose in the black depths of the sea.

Histioteuthis heteropsis (literally “different eyes”) is pink, studded with bioluminescent spots, and quite content to cruise through the “twilight zone” some 650–3300 feet beneath the surface of the ocean. It has one enormous yellow eye and one normal blue eye—as normal as squid eyes get, anyway.

Biologist Kate Thomas of Duke University, lead author on the paper, says she was impressed by the strawberry squid’s strangeness. “You can’t look at one and not wonder what’s going on with them,” she says in the video above.

So she decided to find out. She pulled up 30 years’ worth of undersea video recorded by remotely operated vehicles at the Monterey Bay Aquarium Research Institute and scrolled through, watching the squids’ behavior and looking for clues. She analyzed 152 different H. heteropsis sightings and another nine sightings of its cousin, Stigmatoteuthis dofleini.

The onscreen sightings revealed yet another strawberry squid eccentricity: They like to float along upside down, with their heads pointed toward the ocean floor. But this posture, while whimsical, appears to be practical. The head-down orientation aims the squid’s large eye toward the surface—which is where any light might originate. The little blue eye, better suited for spotting bioluminescence, can keep looking downward into the darkness.

Senior author Sönke Johnsen, Thomas’s advisor, said the squid’s blue eye could only have one job. “There is no way it is able to pick out shapes against the ambient light,” he said in a statement. “And once it is looking for bioluminescence, it doesn’t really need to be particularly big, so it can actually shrivel up a little bit over generations. But the eye looking up actually does benefit from getting a bit bigger.”

It’s an ingenious solution to a low-light situation. “Eyes are really expensive to make and maintain,” Thomas added. “You want eyes just big enough to do what you need to do, but you don’t want to have any bigger eyes because then you are just wasting resources.”

Dogs love food. Some love it more than others, and some of those are Labrador retrievers—the bottomless pits of the canine world. Scientists announced today that they’ve found a gene variant in labs that may explain that constant state of “Please Feed Me.” The findings were published last year in the journal Cell Metabolism.

Dog obesity isn’t something we talk about a lot, but there sure is a lot of it. In the U.S. and other wealthy countries, between 34 and 59 percent of dogs are overweight. And yes, fat dogs are cute, but they’re also in danger of some serious health problems. Canine obesity can cause heart disease, strain on a dog’s joints, diabetes, and can even shorten a dog’s lifespan.

Some breeds, like black labs, chocolate labs, and golden retrievers, are more obesity-prone than others. This is likely because, like many of us, they are highly motivated by food. Labs’ human companions learn quickly that a treat is the trick to getting their dog to behave. But those treats add up.

The domesticated dog, Canis familiaris, is a single species with a lot of variations. Great Danes and Chihuahuas are both dogs, but their bloodlines, and therefore their genes, are dramatically different. And all those differences within a single species make dog breeds a great resource for scientists studying genetics.

Researchers recruited nearly 400 adult Labrador participants. Of those dogs, 310 were pets recruited through an email invitation from the UK Kennel Club, and 80 were part of an assistance-dog breeding colony. Some of the dogs were fat, while others were not, but all of them were healthy, with no pre-existing conditions.

First, the dogs were weighed. Then the scientists collected drool samples from 33 of the dogs and sequenced the DNA within. The dogs’ owners then completed a survey about their labs’ eating habits.

As relatives, of course, the labs had a great deal of genetic material in common with each other and with other dog breeds. But they also had one gene variant that stood out: the deletion of 14 base pairs from a gene called pro-opiomelanocortin, or POMC. Previous studies of this POMC variant have shown a relationship with appetite and a feeling of fullness.

Each dog could have one copy of the POMC variant, two copies, or none. The more copies a dog had, the fatter and more food-motivated it was. And about 23 percent of labs are carrying at least one copy of the variant.

“People who live with Labradors often say they are obsessed by food, and that would fit with what we know about this genetic change,” Cambridge University metabolism expert and lead author Eleanor Raffan said in a press statement.

Her co-author, Stephen O’Rahilly of the Wellcome Trust-Medical Research Council Institute of Science, says these findings have implications beyond kibble. “Common genetic variants affecting the POMC gene are associated with human body weight and there are even some rare obese people who lack a very similar part of the POMC gene to the one that is missing in the dogs. So further research in these obese Labradors may not only help the well-being of companion animals but also have important lessons for human health.”

For a very long time, extraversion (also spelled “extroversion”) was considered the healthy default. It was considered perverse or pathological to avoid crowds or to crave time alone. Fortunately, introversion is far more accepted these days. People self-identify as introverts in their online dating profiles. You can buy “Go Away, I’m Introverting” T-shirts and coffee mugs.

You might be an introvert. You might be an extravert. But it’s more likely you’re an ambivert: that is, somewhere in between.

That’s because extraversion is not an all-or-nothing identity; it’s a spectrum. Psychologists count extraversion—that is, the quality of finding energy and gratification outside of oneself—among the “Big Five” dimensions of personality (along with conscientiousness, agreeableness, openness to new experience, and neuroticism). Each of us is extraverted to some degree, just as we’re conscientious or neurotic. That degree could be zero (although it probably isn’t). Very few people are 100 percent anything.

Personality psychologist Robert McCrae spent his career examining and testing the Big Five model. In a 1992 study [PDF], McCrae and his collaborator found that many people (around 38 percent) fall somewhere in the middle of the spectrum for all five traits, including extraversion.

Adam Grant is a management expert at the Wharton School of Business. In 2013 he conducted a study on 340 call center employees. Since these are people who talk on the phone for a living, you might assume that the majority of them would be extraverts. But two-thirds said they were neither extraverted nor introverted—rather, somewhere in-between. And, more surprising still, these ambiverts outperformed extraverts on their sales calls.

Why? Grant theorized that it’s because phone calls are about more than talking. Sales reps also have to listen. Ambiverts are naturally comfortable doing both, he wrote, which means that they’re “likely to express sufficient assertiveness and enthusiasm to persuade and close a sale, but are more inclined to listen to customers’ interests and less vulnerable to appearing too excited or overconfident.”

Many people who self-identify as introverts or extraverts do so after taking a personality test called the Myers-Briggs Type Indicator (MBTI). Despite its lack of scientific support, the MBTI has become immensely popular, in part because every test result is flattering. It’s a little like a horoscope: We can find ourselves in our readings, but there’s no science to back it up. The MBTI also perpetuates the myth of the all-or-nothing identity, labeling each test-taker as either an introvert or an extravert.

Look, we’re not going to tell you that you can’t be one extreme or the other. But the human experience is rich and complex. Isn’t it better to be flexible?

Have you got a Big Question you’d like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.