How bees defend against some controversial insecticides

Honeybees and bumblebees have a way to resist toxic compounds in some widely used insecticides.

These bees make enzymes that help the insects break down a type of neonicotinoid called thiacloprid, scientists report March 22 in Current Biology. Neonicotinoids have been linked to negative effects on bee health, such as difficulty reproducing in honeybees (SN: 7/26/16, p 16). But bees respond to different types of the insecticides in various ways. This finding could help scientists design versions of neonicotinoids that are less harmful to bees, the researchers say.
Such work could have broad ramifications, says study coauthor Chris Bass, an applied entomologist at the University of Exeter in England. “Bees are hugely important to the pollination of crops and wild flowers and biodiversity in general.”

Neonicotinoids are typically coated on seeds such as corn and sometimes sprayed on crops to protect the plants from insect pests. The chemicals are effective, but their use has been suspected to be involved in worrisome declines in numbers of wild pollinators (SN Online: 4/5/12).

Maj Rundlöf of Lund University in Sweden helped raise the alarm about the insecticides. In 2015, she reported that neonicotinoid-treated crops reduced the populations of bees that fed from the plants. Rundlöf, who was not involved with the new study, says the new research is important because it clarifies differences between the insecticides. “All neonicotinoids are not the same,” she says. “It’s a bit unrealistic to damn a whole group of pesticides.”

Bass and his colleagues, which include scientists from Bayer, one of the main producers of neonicotinoids, investigated resistance to thiacloprid by looking at bees’ defense systems. The team focused on enzymes known as P450s, which can metabolize toxic chemicals, breaking them down before they affect the bee nervous system. The researchers used drugs to inhibit groups of P450 enzymes. When the family enzymes called CYP9Q was inhibited, bees became 170 times as sensitive to thiacloprid, dying from a much smaller dose, the researchers found. Discovering the enzymes’ protective power could lead to more effective ways to simultaneously avoid harming bees and help crops.
“We live in an era that uses pesticides,” Rundlöf says. “We need to figure out the ones that are safest.”

Peruvian fossils yield a four-legged otterlike whale with hooves

An ancient four-legged whale walked across land on hooved toes and swam in the sea like an otter.

The newly discovered species turned up in 2011 in a cache of fossilized bones in Playa Media Luna, a dry coastal area of Peru. Jawbones and teeth pegged it as an ancient cetacean, a member of the whale family. And more bones followed.

“We were definitely surprised to find this type of whale in these layers, but the best surprise was its degree of completeness,” says Olivier Lambert, a paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels.
Jaw, tooth and spine features, described April 4 in Current Biology, don’t quite match anything else in the fossil record, setting the skeleton apart as a new species, dubbed Peregocetus pacificus (meaning “the traveling whale that reached the Pacific Ocean”). At 42.6 million years old, it’s the oldest whale skeleton found in the New World, though some fossilized whale teeth from North America may be even older.

Big, possibly webbed feet and long toes would have allowed P. pacificus to dog-paddle or swim freestyle. And like modern otters and beavers, this whale’s vertebrae suggest that its tail also functioned as a paddle. With tiny hooves and strong legs and hips, the animal could walk on land. But “it was definitely a better swimmer than walker,” Lambert says.

Whales got their start on land and gradually adapted to a water-dwelling lifestyle. The first amphibious whales emerged more than 50 million years ago near what’s now India and Pakistan. The new species shares some similar features with Maiacetus and Rodhocetus, two early whales from that area. P. pacificus’ age supports the idea that whales migrated across the South Atlantic and around South America to the Pacific Ocean in their first 10 million years of existence.

Muons unveiled new details about a void in Egypt’s Great Pyramid

A nebulous void in Egypt’s Great Pyramid of Giza has been unveiled thanks to strange subatomic particles called muons.

Scientists first identified the void in 2016 using muons, heavy relatives of electrons that can penetrate through solid materials. Thought to be a corridor-shaped hole, the void was located near a chevron-shaped structure visible on the pyramid’s north face. Further muon measurements revealed new details of the void’s size and shape, scientists from the ScanPyramids team report March 2 in Nature Communications.
The new muon measurements indicate that the void is a 9-meter-long corridor about 2 meters wide by 2 meters tall, close to the pyramid’s north face. ScanPyramids researchers made additional measurements with ground-penetrating radar and ultrasonic testing, they reported March 2 in NDT & E International. The detailed measurements allowed the scientists to use an endoscope to take images inside the chamber, the team announced. The images reveal a corridor with a vaulted ceiling, presumably one that was hasn’t been seen by humans since the pyramid was built more than 4,500 years ago. The corridor’s purpose is still unclear.
Muons are created when high-energy particles from space called cosmic rays crash into the Earth’s atmosphere. Muons are partially absorbed as they rain down onto structures such as the pyramids. Using detectors placed inside the pyramid, scientists from ScanPyramids zeroed in on regions where more muons made it through, indicating they’d traversed less material, which let them map out the location of the void.

Scientists also recently used muons to probe an ancient Chinese wall (SN: 1/30/23), a nuclear reactor and various volcanoes (SN: 4/22/22).

Artificial intelligence has now pretty much conquered poker

Artificial intelligence has passed the last major milestone in mastering poker: six-player no-limit Texas Hold’em.

Games like poker, with hidden cards and players who bluff, present a greater challenge to AI than games where every player can see the whole board. Over the last few years, computers have become aces at increasingly complicated forms of one-on-one poker, but multiplayer games take that complexity to the next level (SN Online: 5/13/15).

Now, a card shark AI dubbed Pluribus has outplayed more than a dozen elite professionals at six-player Texas Hold’em, researchers report online July 11 in Science. Algorithms that can plot against several adversaries using such spotty information could make savvy business negotiators, political strategists or cybersecurity watchdogs.
Pluribus honed its initial strategy by playing against copies of itself, starting from scratch and gradually learning which actions helped to win. Then, the AI used that intuition for when to hold and when to fold during the first betting round of each hand against five human players.

During subsequent betting rounds, Pluribus fine-tuned its strategy by imagining how the game might play out if it took different actions. Unlike artificial intelligence trained for two-player poker, Pluribus didn’t speculate all the way to the end of the game — which would require too many computations when dealing with so many players (SN: 4/1/17, p. 12). Instead, the AI imagined several moves ahead and decided what to do based on those hypothetical futures and different strategies that players could adopt.

In 10,000 hands of Texas Hold’em, Pluribus competed against five contestants from a pool of 13 professionals, all of whom had won more than $1 million playing poker. Every 100 hands, Pluribus raked in, on average, about $480 from its human competitors.
“This is roughly the amount that elite human professionals aspire to beat weaker players by,” implying that Pluribus was a savvier player than its human opponents, says Noam Brown of Facebook AI Research in New York City. Brown, along with Tuomas Sandholm of Carnegie Mellon University in Pittsburgh, created Pluribus.

Now that AI has poker in the bag, algorithms could test their strategic reasoning in games with more complex hidden information, says computer scientist Viliam Lisý of the Czech Technical University in Prague, who was not involved in the work. In games like Kriegspiel — a chess spin-off where players can’t see each other’s pieces — the unknowns can become far more complicated than a few cards held close to opponents’ chests, Lisý says.

Video games like StarCraft, which allow many more types of moves and free players from rigid, turn-based play, could also serve as new tests of AI cleverness (SN: 5/11/19, p. 34).

Homo sapiens may have brought archery to Europe about 54,000 years ago

Homo sapiens who reached Europe around 54,000 years ago introduced bows and arrows to that continent, a new study suggests.

Researchers examined tiny triangular stone points and other artifacts excavated at a rock-shelter in southern France called Grotte Mandrin. H. sapiens on the move probably brought archery techniques from Africa to Europe, archaeologist Laure Metz of Aix-Marseille University in France and colleagues report February 22 in Science Advances.

“Metz and colleagues demonstrate bow hunting [at Grotte Mandrin] as convincingly as possible without being caught bow-in-hand,” says archaeologist Marlize Lombard of the University of Johannesburg, who did not participate in the new study.
No bows were found at the site. Wooden items such as bows preserve poorly. The oldest intact bows, found in northern European bogs, date to around 11,000 years ago, Metz says.

Previous stone and bone point discoveries suggest that bow-and-arrow hunting originated in Africa between about 80,000 and 60,000 years ago. And previously recovered fossil teeth indicate that H. sapiens visited Grotte Mandrin as early as 56,800 years ago, well before Neandertals’ demise around 40,000 years ago and much earlier than researchers had thought that H. sapiens first reached Europe (SN: 2/9/22).

“We’ve shown that the earliest known Homo sapiens to migrate into Neandertal territories had mastered the use of the bow,” Metz says.

No evidence suggests that Neandertals already present in Europe at that time launched arrows at prey. It’s also unclear whether archery provided any substantial hunting advantages to H. sapiens relative to spears that were thrust or thrown by Neandertals.
Among 852 stone artifacts excavated in a H. sapiens sediment layer at Grotte Mandrin dated to about 54,000 years ago, 196 triangular stone points displayed high-impact damage. Another 15 stone points showed signs of both high-impact damage and alterations caused by butchery activities, such as cutting.

Comparisons of those finds were made to damage on stone replicas of the artifacts that the researchers used as arrowheads shot from bows and as the tips of spears inserted in handheld throwing devices. Additional comparative evidence came from stone and bone arrowheads used by recent and present-day hunting groups.

Impact damage along the edges of stone points from the French site indicated that these implements had been attached at the bottom to shafts.

The smallest Grotte Mandrin points, many with a maximum width of no more than 10 millimeters, could have pierced animals’ hides only when shot from bows as the business ends of arrows, the researchers say. Experiments they conducted with replicas of the ancient stone points found that stone points less than 10 millimeters wide reach effective hunting speeds only when attached to arrow shafts propelled by a bow.

Larger stone points, some of them several times the size of the smaller points, could have been arrowheads or might have tipped spears that were thrown or thrust by hand or launched from handheld spear throwers, the researchers conclude.

Lombard, the University of Johannesburg archaeologist, suspects that the first H. sapiens at the French rock-shelter hunted with bows and arrows as well as with spears, depending on where and what they were hunting. Earlier studies directed by Lombard indicated that sub-Saharan Africans similarly alternated between these two types of hunting weapons starting between about 70,000 and 58,000 years ago.

H. sapiens newcomers to Europe may have learned from Neandertals that spear hunting in large groups takes precedence on frigid landscapes, where bow strings can easily snap and long-distance pursuit of prey is not energy efficient, Lombard says.

But learning about archery from H. sapiens may not have been in the cards for Neandertals. Based on prior analyses of brain impressions on the inside surfaces of fossil skulls, Lombard suspects that Neandertals’ brains did not enable the enhanced visual and spatial abilities that H. sapiens exploited to hunt with bows and arrows.

That’s a possibility, though other controversial evidence suggests that Neandertals behaved no differently from Stone Age H. sapiens (SN: 3/26/20).If Grotte Mandrin Neandertals never hunted with bows and arrows but still survived just fine alongside H. sapiens archers for roughly 14,000 years, reasons for Neandertals’ ultimate demise remain as mysterious as ever.

A few key signs betray betrayal

Whether it’s Katy Perry poaching dancers from once-BFF Taylor Swift or Clytemnestra orchestrating the murder of her husband Agamemnon, betrayal is a dark, persistent part of the human condition. Unlike garden-variety deception, betrayal happens in established relationships, destroying trust that has developed over time. It’s usually unexpected, and it yields a unique, often irreparable, wound. In fact, betrayers have a special place in hell, literarily: In Dante’s Inferno, they occupy the ninth and final circle; mere fraudsters dwell in the eighth.

While most of us are familiar with betrayal, investigating it is really hard. (Consider all the complications of a study that asks people in trusted relationships to betray each other.) Case studies of real betrayals can provide insight after-the-fact, but without a time machine, finding studies that reveal big picture patterns about the lead-up to treachery are scarce.

“We all know betrayal exists,” says Cristian Danescu-Niculescu-Mizil, a computer scientist at Cornell University who spends a lot of time thinking about what language reveals about relationships. “But finding relevant data is really hard.”

So when Danescu-Niculescu-Mizil heard about a Diplomacy, a strategy game rife with betrayal, he figured it might serve as a good proxy for real life treachery. And he was right: Studying the patterns of communication between the players revealed that betrayal is sometimes foreseeable. But like many relationships that collapse in betrayal, teasing out what goes wrong and who is at fault isn’t so easy.
Unlike Risk and other war games, Diplomacy is all about, well, diplomacy (John F. Kennedy and Henry Kissinger reportedly were fans). Set in Europe before World War I, the nations/players have to form alliances to win. But chance is removed from the equation; players don’t roll dice or take turns. There’s only diplomacy: a negotiation phase where players converse, form alliances and gather intelligence (these days, typically online), and a movement phase where everyone’s decisions are revealed and executed all at once. Betrayal is so integral to Diplomacy that, as noted on a “This American Life” episode, stabbing an ally in the back is referred to by the shorthand “stabbing.”

Danescu-Niculescu-Mizil, colleague and fan-of-the-game Jordan Boyd-Graber, and colleagues examined 249 games of Diplomacy with a total of 145,000 messages among players. When they used a computer program to compare exchanges between players whose relationships ended in betrayal with those whose relationships lasted, the computer discerned subtle signals of impending betrayal.

One harbinger was a shift in politeness. Players who were excessively polite in general were more likely to betray, and people who were suddenly more polite were more likely to become victims of betrayal, study coauthor and Cornell graduate student Vlad Niculae reportedJuly 29 at the Annual Meeting of the Association for Computational Linguistics in Beijing. Consider this exchange from one round:

Germany: Can I suggest you move your armies east and then I will support you? Then next year you move [there] and dismantle Turkey. I will deal with England and France, you take out Italy.

Austria: Sounds like a perfect plan! Happy to follow through. And—thank you Bruder!

Austria’s next move was invading German territory. Bam! Betrayal.

An increase planning-related language by the soon-to-be victim also indicated impending betrayal, a signal that emerges a few rounds before the treachery ensues. And correspondence of soon-to-be betrayers had an uptick in positive sentiment in the lead-up to their breach.
Working from these linguistic cues, a computer program could peg future betrayal 57 percent of the time. That might not sound like much, but it was better than the accuracy of the human players, who never saw it coming. And remember that by definition, a betrayer conceals the intention to betray; the breach is unexpected (that whole trust thing). Given that inherent deceit, 57 percent isn’t so bad.

When I spoke to Danescu-Niculescu-Mizil, he said that more important than the clues themselves is the shift in the balance of behavior in the relationship. Positive or negative sentiment of one player isn’t what matters, it’s the asymmetry of the behavior of the two people in the relationship. He likens the linguistic tells to body language: While you wouldn’t use it as a sole basis for decision-making, if you know how to interpret it, it might give you an advantage.

More work is needed to explore whether these patterns exist in real life. And while the research did reveal some patterns, it can’t say anything about cause and effect or who is at fault. Perhaps, for example, the extensive planning of the eventual victims came off as super bossy and frustrating to the eventual betrayer. After all, Clytemnestra’s betrayal of Agamemnon came after he killed their daughter Iphigenia. That kind of bad blood may be unforgivable.

Physicists stored data in quantum holograms made of twisted light

Particles of twisted light that have been entangled using quantum mechanics offer a new approach to dense and secure data storage.

Holograms that produce 3-D images and serve as security features on credit cards are usually made with patterns laid down with beams of laser light. In recent years, physicists have found ways to create holograms with entangled photons instead. Now there is, literally, a new twist to the technology.

Entangled photons that travel in corkscrew paths have resulted in holograms that offer the possibility of dense and ultrasecure data encryption, researchers report in a study to appear in Physical Review Letters.
Light can move in a variety of ways, including the up-and-down and side-to-side patterns of polarized light. But when it carries a type of rotation known as orbital angular momentum, it can also propagate in spirals that resemble twisted rotini pasta.

Like any other photons, the twisted versions can be entangled so that they essentially act as one entity. Something that affects one of an entangled photon pair instantly affects the other, even if they are very far apart.

In previous experiments, researchers have sent data through the air in entangled pairs of twisted photons (SN: 8/5/15). The approach should allow high-speed data transmission because light can come with different amounts of twist, with each twist serving as a different channel of communication.

Now the same approach has been applied to record data in holograms. Instead of transmitting information on multiple, twisted light channels, photon pairs with different amounts of twist create distinct sets of data in a single hologram. The more orbital angular momentum states involved, each with different amounts of twist, the more data researchers can pack into a hologram.

In addition to cramming more data into holograms, increasing the variety of twists used to record the data boosts security. Anyone who wants to read the information out needs to know, or guess, how the light that recorded it was twisted.

For a hologram relying on two types of twist, says physicist Xiangdong Zhang of the Beijing Institute of Technology, you would have to pick the right combination of the twists from about 80 possibilities to decode the data. Bumping that up to combinations of seven distinct twists leads to millions of possibilities. That, Zhang says, “should be enough to ensure our quantum holographic encryption system has enough security level.”
The researchers demonstrated their technique by encoding words and letters in holograms and reading the data back out again with twisted light. Although the researchers produced images from the holographic data, says physicist Hugo Defienne of the Paris Institute of Nanosciences, the storage itself should not be confused with holographic images.

Defienne, who was not involved with the new research, says that other quantum holography schemes, such as his efforts with polarized photons, produce direct images of objects including microscopic structures.

“[Their] idea there is very different . . . from our approach in this sense,” Defrienne says. “They’re using holography to store information,” rather than creating the familiar 3-D images that most people associate with holograms.

The twisted light data storage that Zhang and his colleagues demonstrated is slow, requiring nearly 20 minutes to decode an image of the acronym “BIT,” for the Beijing Institute of Technology where the experiments were performed. And the security that the researchers have demonstrated is still relatively low because they included only up to six forms of twisted light in their experiments.

Zhang is confident that both limitations can be overcome with technical improvements. “We think that our technology has potential application in quantum information encryption,” he says, “especially quantum image encryption.”

76 percent of well-known insects fall outside protected areas

The existing boundaries of national parks and other habitat preserves aren’t enough to protect more than three-quarters of the world’s well-studied insects.

The finding, reported February 1 in One Earth, shows that people who design nature preserves “don’t really think about insects that much,” says coauthor Shawan Chowdhury, an ecologist at the German Centre for Integrative Biodiversity Research in Leipzig.

That’s a problem because insect populations around the globe are plummeting, a growing body of research suggests, probably due to climate change and human development (SN: 4/26/22). For instance, insect abundance in Puerto Rico has dropped by up to 98 percent over the last 35 years.
Threats to insect survival could have ripple effects on plants and other animals. Insects help form the foundation for many ecosystems: They pollinate around 80 percent of all plant species and serve as a staple in the diets of hundreds of thousands of animals (and the occasional carnivorous plant).

One way to avert insect extinctions is to set aside the land they need to survive. But scientists know the ranges for only about 100,000 of the estimated 5.5 million insect species. To determine how well existing protected areas may be aiding insect conservation, Chowdhury and colleagues mapped the known habitats of about 89,000 of those species and compared the ranges with the boundaries of preserves from the World Database on Protected Areas.

Overall, these spaces don’t safeguard enough habitat for 67,384 insect species — about 76 percent of the species included in the study — the team found. Roughly 2 percent of species do not overlap with protected areas at all.

Conserving insects, Chowdhury says, will mean setting aside more insect-friendly spaces in the years ahead.

Earth’s inner core may be reversing its rotation

Our planet may have had a recent change of heart.

Earth’s inner core may have temporarily stopped rotating relative to the mantle and surface, researchers report in the January 23 Nature Geoscience. Now, the direction of the inner core’s rotation may be reversing — part of what could be a roughly 70-year-long cycle that may influence the length of Earth’s days and its magnetic field — though some researchers are skeptical.

“We see strong evidence that the inner core has been rotating faster than the surface, [but] by around 2009 it nearly stopped,” says geophysicist Xiaodong Song of Peking University in Beijing. “Now it is gradually mov[ing] in the opposite direction.”
Such a profound turnaround might sound bizarre, but Earth is volatile (SN: 1/13/21). Bore through the ever-shifting crust and you’ll enter the titanic mantle, where behemoth masses of rock flow viscously over spans of millions of years, sometimes upwelling to excoriate the overlying crust (SN: 1/11/17, SN: 3/2/17, SN: 2/4/21). Delve deeper and you’ll reach Earth’s liquid outer core. Here, circulating currents of molten metals conjure our planet’s magnetic field (SN: 9/4/15). And at the heart of that melt, you’ll find a revolving, solid metal ball about 70 percent as wide as the moon.

This is the inner core (SN: 1/28/19). Studies have suggested that this solid heart may rotate within the liquid outer core, compelled by the outer core’s magnetic torque. Researchers have also argued the mantle’s immense gravitational pull may apply an erratic brake on the inner core’s rotation, causing it to oscillate.

Evidence for the inner core’s fluctuating rotation first emerged in 1996. Geophysicist Paul Richards of Columbia University’s Lamont-Doherty Earth Observatory in Palisades, N.Y., and Song, then also at Lamont-Doherty, reported that over a span of three decades, seismic waves from earthquakes took different amounts of time to traverse Earth’s solid heart.

The researchers inferred that the inner core rotates at a different speed than the mantle and crust, causing the time differences. The planet spins roughly 360 degrees in a day. Based on their calculations, the researchers estimated that the inner core, on average, rotates about 1 degree per year faster than the rest of Earth.

But other researchers have questioned that conclusion, some suggesting that the core spins slower than Song and Richards’ estimate or doesn’t spin differently at all.

In the new study, while analyzing global seismic data stretching back to the 1990s, Song and geophysicist Yi Yang — also at Peking University — made a surprising observation.
Before 2009, seismic waves generated by sequences and pairs of repeating earthquakes — known as multiplets and doublets — traveled at different rates through the inner core. This indicated the waves from recurring quakes were crossing different parts of the inner core, and that the inner core was rotating at a different pace than the rest of Earth, aligning with Song’s previous research.

But around 2009, the differences in travel times vanished. That suggested the inner core had ceased rotating with respect to the mantle and crust, Yang says. After 2009, these differences returned, but the researchers inferred that the waves were crossing parts of the inner core that suggested it was now rotating in the opposite direction relative to the rest of Earth.

The researchers then pored over records of Alaskan earthquake doublets dating to 1964. While the inner core appeared to rotate steadily for most of that time, it seems to have made another reversal in rotation in the early 1970s, the researchers say.

Song and Yang infer that the inner core may oscillate with a roughly 70-year periodicity — switching directions every 35 years or so. Because the inner core is gravitationally linked to the mantle and magnetically linked to the outer core, the researchers say these oscillations could explain known 60- to 70-year variations in the length of Earth’s days and the behavior of the planet’s magnetic field. However, more work is needed to pin down what mechanisms might be responsible.

But not all researchers are on board. Yang and Song “identif[y] this recent 10-year period [that] has less activity than before, and I think that’s probably reliable,” says geophysicist John Vidale of the University of Southern California in Los Angeles, who was not involved in the research. But beyond that, Vidale says, things get contentious.

In 2022, he and a colleague reported that seismic waves from nuclear tests show the inner core may reverse its rotation every three years or so. Meanwhile, other researchers have proposed that the inner core isn’t moving at all. Instead, they say, changes to the shape of the inner core’s surface could explain the differences in wave travel times.

Future observations will probably help disentangle the discrepancies between these studies, Vidale says. For now, he’s unruffled by the purported chthonic standstill. “In all likelihood, it’s irrelevant to life on the surface, but we don’t actually know what’s happening,” he says. “It’s incumbent on us to figure it out.”