上海后花园1314

Carlos Jared discovered the first known venomous frog by accident. And it took him a long time to connect his pain with tree frogs that head-butted his hand.

Jared, now at the Butantan Institute in São Paulo, got his first hint of true venom when collecting yellow-skinned frogs (Corythomantis greeningi) among cacti and scrubby trees in Brazil’s dry Caatinga region. For hours after grabbing the frogs, intense pain radiated up his arm for no obvious reason.
He knew frogs have no fangs to deliver toxin. Many frog species can poison an animal that touches them, but they’re poisonous. True venomous animals actively deliver toxins.

Jared realized head-butting delivers venom only when he saw the frogs’ upper lips under a microscope. Bone spikes erupted near venom glands that looked “giant,” he says. As a frog’s lips curl back, glands dribble toxins onto spikes sticking out from the skull and the frog pokes them against foes.

Gram for gram, the frog venom is almost twice as dangerous to mammals as typical venom of the feared Bothrops pit vipers, Jared, Edmund Brodie Jr. of Utah State University in Logan and their colleagues report online August 6 in Current Biology.
The researchers also report a second spiky-skulled venomous frog, Aparasphenodon brunoi, which is a forest species not very closely related to yellow-skinned frogs. It head-butts toxins 25 times as powerful as typical pit viper venom, a phenomenon luckily not discovered by handling.

Accidents are how most venomous animals first come to scientific notice, Brodie says. Early in his career, he discovered details of fire salamander venom by tickling a new specimen with a piece of grass. He was showing students how toxins ooze from its skin and “it sprayed me right in the eye,” he says. “I was immediately blinded.”

“I ran to the sink and ran water in my eye for about 20 minutes,” he says. “The toxin isn’t water soluble, so it didn’t help much. It was extraordinarily painful,” he notes in mild tones. Also, “the first time you observe something like that, you’re not sure it’s temporary blindness.” It was.

Venomous amphibians may be more common than people expect, Brodie says. Now that the researchers know about bone points for venom delivery, they want to investigate some salamanders with ribs that punch through the skin. And at least three more frogs grow suspicious spines around their heads. “It’s not Kermit anymore,” he says.

Editor’s Note: This story was updated on August 13, 2015, to clarify the habitat differences between the two venomous frogs.

Boa constrictors don’t so much suffocate prey as break their hearts. It turns out that the snakes kill like demon blood pressure cuffs, squeezing down circulation to its final stop. The notion that constrictors slay by preventing breathing turns out to be wrong.

The snakes don’t need limbs, or even venom, to bring down an animal of their own size. “Imagine you’re killing and swallowing a 150-pound animal in one meal — with no hands or legs!” animal ecologist Scott Boback tells his students at Dickinson College in Carlisle, Pa., to convey what extraordinary hunters snakes are. Speed matters with prey flailing claws, hooves or other weaponry the snake lacks. Embracing prey into heart failure is faster than suffocating it and appeared in different forms multiple times in snake history.
Ambushing birds, monkeys and a wide range of other animals from Mexico south to Argentina, the iconic Boa constrictor attacks in much the same way each time. The snake cinches a loop or two around the upper body of prey, pressing against its victim hard enough to starve organs of oxygenated blood.

“It’s not some unbelievable amount of pressure,” says Boback, whose arms get snaked now and then. “It stings a little — you can kind of feel the blood stop,” he says.
Within six seconds of looping around an anesthetized lab rat, a boa constrictor squeezes enough to halve blood pressure in a rear-leg artery. Blood that should surge through the artery lies dammed behind snake coils in the rat’s upper body. And back pressure keeps the rat heart from pumping out new blood. Circulation falters and fails. Boas release their grip after about six minutes on average, Boback and his colleagues report in the July 15 Journal of Experimental Biology.

Then the boa swallows the catch whole. A rat about a quarter of the snake’s weight disappears down the gullet in a couple of minutes. Moveable bones in the head help the snake make the gulp, as does a dimple of stretchy cartilage that lets the chin open wide. But what people most often tell Boback — that snake jaws must separate at the back — is just another serpentine myth.

Icicles made from pure water give scientists brain freeze.

In nature, most icicles are made from water with a hint of salt. But lab-made icicles free from salt disobey a prominent theory of how icicles form, and it wasn’t clear why. Now, a study is helping to melt away the confusion.

Natural icicles tend to look like skinny cones with rippled surfaces — the result of a thin film of water that coats the ice, researchers think (SN: 11/24/13). As icicles grow, the film freezes. Any preexisting small bumps in the icicle get magnified into large ripples because the water layer is thinner above the bumps and can freeze more readily. But this theory fails to explain the salt-free variety, which have more irregular shapes reminiscent of drippy candles, says physicist Menno Demmenie of the University of Amsterdam.
So Demmenie and colleagues grew icicles in the lab, adding a blue dye that was visible only when the water was liquid. Salted icicles not only had ripples, but they also were covered in a thin, blue film. Icicles made from pure water had no such film. Only small droplets of blue appeared on those icicles, the team reports in the February Physical Review Applied.

In icicles with salt, the temperature at which the water on the surface freezes is lowered, allowing a liquid layer to coat the entire icicle. Without the salt, icicles must build up drop by drop.

The James Webb Space Telescope has spotted the earliest known galaxy to abruptly stop forming stars.

The galaxy, called GS-9209, quenched its star formation more than 12.5 billion years ago, researchers report January 26 at arXiv.org. That’s only a little more than a billion years after the Big Bang. Its existence reveals new details about how galaxies live and die across cosmic time.

“It’s a remarkable discovery,” says astronomer Mauro Giavalisco of the University of Massachusetts Amherst, who was not involved in the new study. “We really want to know when the conditions are ripe to make quenching a widespread phenomenon in the universe.” This study shows that at least some galaxies quenched when the universe was young.
GS-9209 was first noticed in the early 2000s. In the last few years, observations with ground-based telescopes identified it as a possible quenched galaxy, based on the wavelengths of light it emits. But Earth’s atmosphere absorbs the infrared wavelengths that could confirm the galaxy’s distance and that its star-forming days were behind it, so it was impossible to know for sure.

So astrophysicist Adam Carnall and colleagues turned to the James Webb Space Telescope, or JWST. The observatory is very sensitive to infrared light, and it’s above the blockade of Earth’s atmosphere (SN: 1/24/22). “This is why JWST exists,” says Carnall, of the University of Edinburgh. JWST also has much greater sensitivity than earlier telescopes, letting it see fainter, more distant galaxies. While the largest telescopes on the ground could maybe see GS-9209 in detail after a month of observing, “JWST can pick this stuff up in a few hours.”

Using JWST observations, Carnall and colleagues found that GS-9209 formed most of its stars during a 200-million-year period, starting about 600 million years after the Big Bang. In that cosmically brief moment, it built about 40 billion solar masses’ worth of stars, about the same as the Milky Way has.

That quick construction suggests that GS-9209 formed from a massive cloud of gas and dust collapsing and igniting stars all at once, Carnall says. “It’s pretty clear that the vast majority of the stars that are currently there formed in this big burst.”

Astronomers used to think this mode of galaxy formation, called monolithic collapse, was the way that most galaxies formed. But the idea has fallen out of favor, replaced by the notion that large galaxies form from the slow merging of many smaller ones (SN: 5/17/21).

“Now it looks like, at least for this object, monolithic collapse is what happened,” Carnall says. “This is probably the clearest proof yet that that kind of galaxy evolution happens.”
As to what caused the galaxy’s star-forming frenzy to suddenly stop, the culprit appears to be an actively feeding black hole. The JWST observations detected extra emission of infrared light associated with a rapidly swirling mass of energized hydrogen, which is a sign of an accreting black hole. The black hole appears to be up to a billion times the mass of the sun.

To reach that mass in less than a billion years after the birth of the universe, the black hole must have been feeding even faster earlier on in its life, Carnall says (SN: 3/16/18). As it gorged, it would have collected a glowing disk of white-hot gas and dust around it.

“If you have all that radiation spewing out of the black hole, any gas that’s nearby is going to be heated up to an incredible extent, which stops it from falling into stars,” Carnall says.

More observations with future telescopes, like the planned Extremely Large Telescope in Chile, could help figure out more details about how the galaxy was snuffed out.

MIT chemist Admir Masic really hoped his experiment wouldn’t explode.

Masic and his colleagues were trying to re-create an ancient Roman technique for making concrete, a mix of cement, gravel, sand and water. The researchers suspected that the key was a process called “hot mixing,” in which dry granules of calcium oxide, also called quicklime, are mixed with volcanic ash to make the cement. Then water is added.

Hot mixing, they thought, would ultimately produce a cement that wasn’t completely smooth and mixed, but instead contained small calcium-rich rocks. Those little rocks, ubiquitous in the walls of the Romans’ concrete buildings, might be the key to why those structures have withstood the ravages of time.
That’s not how modern cement is made. The reaction of quicklime with water is highly exothermic, meaning that it can produce a lot of heat — and possibly an explosion.

“Everyone would say, ‘You are crazy,’” Masic says.

But no big bang happened. Instead, the reaction produced only heat, a damp sigh of water vapor — and a Romans-like cement mixture bearing small white calcium-rich rocks.

Researchers have been trying for decades to re-create the Roman recipe for concrete longevity — but with little success. The idea that hot mixing was the key was an educated guess.

Masic and colleagues had pored over texts by Roman architect Vitruvius and historian Pliny, which offered some clues as to how to proceed. These texts cited, for example, strict specifications for the raw materials, such as that the limestone that is the source of the quicklime must be very pure, and that mixing quicklime with hot ash and then adding water could produce a lot of heat.

The rocks were not mentioned, but the team had a feeling they were important.
“In every sample we have seen of ancient Roman concrete, you can find these white inclusions,” bits of rock embedded in the walls. For many years, Masic says, the origin of those inclusions was unclear — researchers suspected incomplete mixing of the cement, perhaps. But these are the highly organized Romans we’re talking about. How likely is it that “every operator [was] not mixing properly and every single [building] has a flaw?”

What if, the team suggested, these inclusions in the cement were actually a feature, not a bug? The researchers’ chemical analyses of such rocks embedded in the walls at the archaeological site of Privernum in Italy indicated that the inclusions were very calcium-rich.

That suggested the tantalizing possibility that these rocks might be helping the buildings heal themselves from cracks due to weathering or even an earthquake. A ready supply of calcium was already on hand: It would dissolve, seep into the cracks and re-crystallize. Voila! Scar healed.

But could the team observe this in action? Step one was to re-create the rocks via hot mixing and hope nothing exploded. Step two: Test the Roman-inspired cement. The team created concrete with and without the hot mixing process and tested them side by side. Each block of concrete was broken in half, the pieces placed a small distance apart. Then water was trickled through the crack to see how long it took before the seepage stopped.

“The results were stunning,” Masic says. The blocks incorporating hot mixed cement healed within two to three weeks. The concrete produced without hot mixed cement never healed at all, the team reports January 6 in Science Advances.

Cracking the recipe could be a boon to the planet. The Pantheon and its soaring, detailed concrete dome have stood nearly 2,000 years, for instance, while modern concrete structures have a lifespan of perhaps 150 years, and that’s a best case scenario (SN: 2/10/12). And the Romans didn’t have steel reinforcement bars shoring up their structures.

More frequent replacements of concrete structures means more greenhouse gas emissions. Concrete manufacturing is a huge source of carbon dioxide to the atmosphere, so longer-lasting versions could reduce that carbon footprint. “We make 4 gigatons per year of this material,” Masic says. That manufacture produces as much as 1 metric ton of CO2 per metric ton of produced concrete, currently amounting to about 8 percent of annual global CO2 emissions.

Still, Masic says, the concrete industry is resistant to change. For one thing, there are concerns about introducing new chemistry into a tried-and-true mixture with well-known mechanical properties. But “the key bottleneck in the industry is the cost,” he says. Concrete is cheap, and companies don’t want to price themselves out of competition.

The researchers hope that reintroducing this technique that has stood the test of time, and that could involve little added cost to manufacture, could answer both these concerns. In fact, they’re banking on it: Masic and several of his colleagues have created a startup they call DMAT that is currently seeking seed money to begin to commercially produce the Roman-inspired hot-mixed concrete. “It’s very appealing simply because it’s a thousands-of-years-old material.”

Tiny, pond-dwelling Halteria ciliates are virovores, able to survive on a virus-only diet, researchers report December 27 in Proceedings of the National Academy of Sciences. The single-celled creatures are the first known to thrive when viruses alone are on the menu.

Scientists already knew that some microscopic organisms snack on aquatic viruses such as chloroviruses, which infect and kill algae. But it was unclear whether viruses alone could provide enough nutrients for an organism to grow and reproduce, says ecologist John DeLong of the University of Nebraska–Lincoln.
In laboratory experiments, Halteria that were living in water droplets and given only chloroviruses for sustenance reproduced, DeLong and colleagues found. As the number of viruses in the water dwindled, Halteria numbers went up. Ciliates without access to viral morsels, or any other food, didn’t multiply. But Paramecium, a larger microbe, didn’t thrive on a virus-only diet, hinting that viruses can’t satisfy the nutritional requirements for all ciliates to grow.

Viruses could be a good source of phosphorus, which is essential for making copies of genetic material, DeLong says. But it probably takes a lot of viruses to account for a full meal.

In the lab, each Halteria microbe ate about 10,000 to 1 million viruses daily, the team estimates. Halteria in small ponds with abundant viral snacks might chow down on about a quadrillion viruses per day.

These feasts could shunt previously unrecognized energy into the food web, and add a new layer to the way viruses move carbon through an ecosystem — if it happens in the wild, DeLong says (SN: 6/9/16). His team plans to start finding out once ponds in Nebraska thaw.

In Appalachia’s coal country, researchers envision turning toxic waste into treasure. The pollution left behind by abandoned mines is an untapped source of rare earth elements.

Rare earths are a valuable set of 17 elements needed to make everything from smartphones and electric vehicles to fluorescent bulbs and lasers. With global demand skyrocketing and China having a near-monopoly on rare earth production — the United States has only one active mine — there’s a lot of interest in finding alternative sources, such as ramping up recycling.
Pulling rare earths from coal waste offers a two-for-one deal: By retrieving the metals, you also help clean up the pollution.

Long after a coal mine closes, it can leave a dirty legacy. When some of the rock left over from mining is exposed to air and water, sulfuric acid forms and pulls heavy metals from the rock. This acidic soup can pollute waterways and harm wildlife.

Recovering rare earths from what’s called acid mine drainage won’t single-handedly satisfy rising demand for the metals, acknowledges Paul Ziemkiewicz, director of the West Virginia Water Research Institute in Morgantown. But he points to several benefits.

Unlike ore dug from typical rare earth mines, the drainage is rich with the most-needed rare earth elements. Plus, extraction from acid mine drainage also doesn’t generate the radioactive waste that’s typically a by-product of rare earth mines, which often contain uranium and thorium alongside the rare earths. And from a practical standpoint, existing facilities to treat acid mine drainage could be used to collect the rare earths for processing. “Theoretically, you could start producing tomorrow,” Ziemkiewicz says.

From a few hundred sites already treating acid mine drainage, nearly 600 metric tons of rare earth elements and cobalt — another in-demand metal — could be produced annually, Ziemkiewicz and colleagues estimate.

Currently, a pilot project in West Virginia is taking material recovered from an acid mine drainage treatment site and extracting and concentrating the rare earths.

If such a scheme proves feasible, Ziemkiewicz envisions a future in which cleanup sites send their rare earth hauls to a central facility to be processed, and the elements separated. Economic analyses suggest this wouldn’t be a get-rich scheme. But, he says, it could be enough to cover the costs of treating the acid mine drainage.

In full swing
The swaying feeling in jazz music that compels feet to tap may arise from near-imperceptible delays in musicians’ timing, Nikk Ogasa reported in “Jazz gets its swing from small, subtle delays” (SN: 11/19/22, p. 5).

Reader Oda Lisa, a self-described intermediate saxophonist, has noticed these subtle delays while playing.“I recorded my ‘jazzy’ version of a beloved Christmas carol, which I sent to a friend of mine,” Lisa wrote. “She praised my effort overall, but she suggested that I get a metronome because the timing wasn’t consistent. My response was that I’m a slave to the rhythm that I hear in my head. I think now I know why.”
On the same page
Murky definitions and measurements impede social science research, Sujata Gupta reported in “Fuzzy definitions mar social science” (SN: 11/19/22, p. 10).

Reader Linda Ferrazzara found the story thought-provoking. “If there’s no consensus on the terms people use … then there can be no productive discussion or conversation. People end up talking and working at cross-purposes with no mutual understanding or progress,” Ferrazzara wrote.

Fly me to the moon
Space agencies are preparing to send the next generation of astronauts to the moon and beyond. Those crews will be more diverse in background and expertise than the crews of the Apollo missions, Lisa Grossman reported in “Who gets to go to space?” (SN: 12/3/22, p. 20).

“It is great to see a broader recognition of the work being done to make spaceflight open to more people,” reader John Allen wrote. “Future space travel will and must accommodate a population that represents humanity. It won’t be easy, but it will be done.”

The story also reminded Allen of the Gallaudet Eleven, a group of deaf adults who participated in research done by NASA and the U.S. Navy in the 1950s and ’60s. Experiments tested how the volunteers responded (or didn’t) to a range of scenarios that would typically induce motion sickness, such as a ferry ride on choppy seas. Studying how the body’s sensory systems work without the usual gravitational cues from the inner ear allowed scientists to better understand motion sickness and the human body’s adaptation to spaceflight.

Sweet dreams are made of this
A memory-enhancing method that uses sound cues may boost an established treatment for debilitating nightmares, Jackie Rocheleau reported in “L­earning trick puts nightmares to bed” (SN: 12/3/22, p. 11).

Reader Helen Leaver shared her trick to a good night’s sleep: “I learned that I was having strong unpleasant adventures while sleeping, and I would awaken hot and sweaty. By eliminating the amount of heat from bedding and an electrically heated mattress pad, I now sleep well without those nightmares.”
Pest perspectives
In “Why do we hate pests?” (SN: 12/3/22, p. 26), Deborah Balthazar interviewed former Science News Explores staff writer Bethany Brookshire about her new book, Pests. The book argues that humans — influenced by culture, class, colonization and much more — create animal villains.

The article prompted reader Doug Clapp to reflect on what he considers pests or weeds. “A weed is a plant in the wrong place, and a pest is an animal in the wrong place,” Clapp wrote. But what’s considered “wrong” depends on the humans who have power over the place, he noted. “Grass in a lawn can be a fine thing. Grass in a garden choking the vegetables I’m trying to grow becomes a weed. Mice in the wild don’t bother me. Field mice migrating into my house when the weather cools become a pest, especially when they eat into my food and leave feces behind,” Clapp wrote.

The article encouraged Clapp to look at pests through a societal lens: “I had never thought of pests in terms of high-class or low-class. Likewise, the residual implications of [colonization]. Thanks for provoking me to consider some of these issues in a broader context.”

As far back as roughly 25,000 years ago, Ice Age hunter-gatherers may have jotted down markings to communicate information about the behavior of their prey, a new study finds.

These markings include dots, lines and the symbol “Y,” and often accompany images of animals. Over the last 150 years, the mysterious depictions, some dating back nearly 40,000 years, have been found in hundreds of caves across Europe.

Some archaeologists have speculated that the markings might relate to keeping track of time, but the specific purpose has remained elusive (SN: 7/9/19). Now, a statistical analysis, published January 5 in Cambridge Archeological Journal, presents evidence that past people may have been recording the mating and birthing schedule of local fauna.
By comparing the marks to the animals’ life cycles, researchers showed that the number of dots or lines in a given image strongly correlates to the month of mating across all the analyzed examples, which included aurochs (an extinct species of wild cattle), bison, horses, mammoth and fish. What’s more, the position of the symbol “Y” in a sequence was predictive of birth month, suggesting that “Y” signifies “to give birth.”

The finding is one of the earliest records of a coherent notational system, the researchers say. It indicates that people at the time were able to interpret the meaning of an item’s position in a sequence and plan ahead for the distant future using a calendar of sorts — reinforcing the suggestion that they were capable of complex cognition.
“This is a really big deal cognitively,” says Ben Bacon, an independent researcher based in London. “We’re dealing with a system that has intense organization, intense logic to it.”

A furniture conservator by day, Bacon spent years poring through scientific articles to compile over 800 instances of these cave markings. From his research and reading the literature, he reasoned that the dots corresponded to the 13 lunar cycles in a year. But he thought that the hunter-gatherers would’ve been more concerned with seasonal changes than the moon.

In the new paper, he and colleagues argue that rather than pinning a calendar to astronomical events like the equinox, the hunter-gatherers started their calendar year with the snowmelt in the spring. Not only would the snowmelt be a clear point of origin, but the meteorological calendar would also account for differences in timing across locations.
For example, though snowmelt would start on different dates in different latitudes, bison would always mate approximately four lunar cycles — or months — after that region’s snowmelt, as indicated by four dots or lines.

“This is why it’s such a clever system, because it’s based on the universal,” Bacon says. “Which means if you migrate from the Pyrenees to Belgium, you can just use the same calendar.”

He needed data to prove his idea. After compiling the markings, he worked with academic researchers to identify the timing of migration, mating and birth for common Ice Age animals targeted by hunter-gatherers by using archaeological data or comparing with similar modern animals. Next, the researchers determined if the marks aligned significantly with important life events based on this calendar. When the team ran the statistical analysis, the results strongly supported Bacon’s theory.

When explaining the markings, “we’ve argued for notational systems before, but it’s always been fairly speculative as to what the people were counting and why they were counting,” says Brian Hayden, an archaeologist at Simon Fraser University in Burnaby, British Columbia, who peer-reviewed the paper. “This adds a lot more depth and specificity to why people were keeping calendars and how they were using them.”

Linguistic experts argue that, given the lack of conventional syntax and grammar, the marks wouldn’t be considered writing. But that doesn’t make the finding inherently less exciting, says paleoanthropologist Genevieve von Petzinger of the Polytechnic Institute of Tomar in Portugal, who wasn’t involved in the study. Writing systems are often mistakenly considered a pinnacle of achievement, when in fact writing would be developed only in cultural contexts where it’s useful, she says. Instead, it’s significant that the marks provide a way to keep records outside of the mind.

“In a way, that was the huge cognitive leap,” she says. “Suddenly, we have the ability to preserve [information] beyond the moment. We have the ability to transmit it across space and time. Everything starts to change.”

The debate over these marks’ meanings continues. Archaeologist April Nowell doesn’t buy many of the team’s assumptions. “It boggles my mind why one would need a calendar … to predict that animals were going to have offspring in the spring,” says Nowell, of the University of Victoria in British Columbia. “The amount of information that this calendar is providing, if it really is a calendar, is quite minimal.”

Hayden adds that, while the basic pattern would still hold, some of the cave marks had “wiggle room for interpretation.” The next step, he says, will be to review and verify the interpretations of the marks.

Prairie voles have long been heralded as models of monogamy. Now, a study suggests that the “love hormone” once thought essential for their bonding — oxytocin — might not be so necessary after all.

Interest in the romantic lives of prairie voles (Microtus ochrogaster) was first sparked more than 40 years ago, says Devanand Manoli, a biologist at the University of California, San Francisco. Biologists trying to capture voles to study would frequently catch two at a time, because “what they were finding were these male-female pairs,” he says. Unlike many other rodents with their myriad partners, prairie voles, it turned out, mate for life (SN: 10/5/15).
Pair-bonded prairie voles prefer each other’s company over a stranger’s and like to huddle together both in the wild and the lab. Because other vole species don’t have social behaviors as complex as prairie voles do, they have been a popular animal system for studying how social behavior evolves.

Research over the last few decades has implicated a few hormones in the brain as vital for proper vole manners, most notably oxytocin, which is also important for social behavior in humans and other animals.

Manoli and colleagues thought the oxytocin receptor, the protein that detects and reacts to oxytocin, would be the perfect test target for a new genetic engineering method based on CRISPR technology, which uses molecules from bacteria to selectively turn off genes. The researchers used the technique on vole embryos to create animals born without functioning oxytocin receptors. The team figured that the rodents wouldn’t be able to form pair-bonds — just like voles in past experiments whose oxytocin activity was blocked with drugs.

Instead, Manoli says, the researchers got “a big surprise.” The voles could form pair-bonds even without oxytocin, the team reports in the March 15 Neuron.

“I was very surprised by their results,” says Larry Young, a biologist at Emory University in Atlanta, who was not involved with the study but has studied oxytocin in prairie voles for decades.

A key difference between the new study and past studies that used drugs to block oxytocin is the timing of exactly when the hormone’s activity is turned off. With drugs, the voles are adults and have had exposure to oxytocin in their brains before the shutoff. With CRISPR, “these animals are born never experiencing oxytocin signaling in the brain,” says Young, whose research group has recently replicated Manoli’s experiment and found the same result.

It may be, Young says, that pair-bonding is controlled by a brain circuit that typically becomes dependent on oxytocin through exposure to it during development, like a symphony trained by a conductor. Suddenly remove that conductor and the symphony will sound discordant, whereas a jazz band that’s never practiced with a conductor fares just fine without one.
Manoli agrees that the technique’s timing matters. A secondary reason for the disparity, he says, could be that drugs often have off-target effects, such that the chemicals meant to block oxytocin could have been doing other things in the voles’ brains to affect pair-bonding. But Young disagrees. “I don’t believe that,” he says. “The [drug] that people use is very selective,” not even binding to the receptor of oxytocin’s closest molecular relative, vasopressin.

Does this result mean that decades of past work on pair-bonding has been upended? Not quite.

“It shows us that this is a much more complicated question,” Manoli says. “The pharmacologic manipulations … suggested that [oxytocin] plays a critical role. The question is, what is that role?”

The new seemingly startling result makes sense if you look at the big picture, Manoli says. The ability for voles to pair-bond is “so critical for the survival of the species,” he says. “From a genetics perspective, it may make sense that there isn’t a single point of failure.”

The group now hopes to look at how other hormones, like vasopressin, influence pair-bonding using this relatively new genetic technique. They are also looking more closely at the voles’ behavior to be sure that the CRISPR gene editing didn’t alter it in a way they haven’t noticed yet.

In the game of vole “love,” it looks like we’re still trying to understand all the players.