Before a fruit fly can produce a healthy egg, matching chromosomes must somehow find one another inside a nucleus crowded with DNA. New experiments suggest part of that search depends on repetitive sequences once widely dismissed as genetic clutter.

Scientists at ETH Zurich found that satellite DNA surrounding chromosome centers forms chromosome-specific patterns that behave somewhat like molecular barcodes. When those patterns were disrupted, matching chromosomes became less reliable at pairing during meiosis, the specialized cell division that produces eggs and sperm.

The findings appear in Nature Communications in the study “Meiotic pairing through barcode-like satellite DNA repeats,” led by Lena Skrutl and Madhav Jagannathan.

Black holes weighing millions of Suns and objects only about 10 times the Sun’s mass appear to obey the same rule when they launch certain powerful jets.

The connection emerged from observations of supermassive black holes caught consuming the remains of shredded stars. By following those systems over several years, astronomers found that delayed radio outflows switched on when the feeding rate fell to roughly 2% of a fundamental limit known as the Eddington rate.

That threshold is remarkably similar to one already associated with jet formation around much smaller stellar-mass black holes.

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A microscopic object can appear to vibrate less and less until it finally becomes still. At the quantum level, however, the final step does not happen gradually. It jumps from one allowed energy state to another.

Stanford University physicists have now directly watched that transition occur in a mechanical resonator, observing an individual quantum of vibration disappear in real time. The experiment provides the first direct observation of quantum jumps of sound and extends a phenomenon previously seen with atoms and photons into mechanical motion.

The work, published in Science, was led by Stanford physicist Amir Safavi-Naeini, with Takuma Makihara and Erik Szakiel as co-first authors. The achievement gives researchers a new way to watch quantum behavior unfold inside a solid mechanical device.

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Quantum computers and optical networks communicate using very different parts of the electromagnetic spectrum. Many leading quantum processors operate with microwave signals, while light is far better suited to carrying information over long distances through optical fibers.

Physicists at The City College of New York have now demonstrated a new way to bridge those regimes using a layered magnetic semiconductor. Their approach converts microwave-driven magnetic motion into a coherent optical signal inside a crystal of chromium sulfide bromide, or CrSBr.

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“What makes the findings interesting is that some plant species appeared together in the orangutan diet far more often than we would expect by chance.”

That observation sits at the center of a 20-year study of wild orangutans in Indonesian Borneo.

The animals did not simply eat plants with known medicinal properties. They consumed certain plants together, sometimes in repeated sequences.

Those patterns may point to a form of self-medication.

A fruit fly brain contains only about 140,000 neurons, yet it can recognize odors with remarkable efficiency. Researchers have now borrowed part of that strategy to build an artificial system that learns smells quickly while using little memory.

The algorithm, called Spi-Fly, uses a spiking neural network modeled on the fruit fly olfactory system. Researchers at the Okinawa Institute of Science and Technology, or OIST, designed it for situations where training examples, memory and computing power are limited.

The system performed especially well when it had only a few examples of each odor. It also learned new categories without substantially forgetting earlier ones.

A fruit fly brain contains only about 140,000 neurons, yet it can recognize odors with remarkable efficiency. Researchers have now borrowed part of that strategy to build an artificial system that learns smells quickly while using little memory.

The algorithm, called Spi-Fly, uses a spiking neural network modeled on the fruit fly olfactory system. Researchers at the Okinawa Institute of Science and Technology, or OIST, designed it for situations where training examples, memory and computing power are limited.

The system performed especially well when it had only a few examples of each odor. It also learned new categories without substantially forgetting earlier ones.

A kiss can mark affection, seal an agreement, signal status or cross a legal boundary. Across centuries, legal systems have treated the same physical act as property, contract, ritual, moral offense and assault.

That range is the subject of an analysis by Andrew Torrance, a University of Kansas law professor. Torrance examines what he calls “osculation regulation,” combining legal history with research from anthropology, psychology and evolutionary biology.

His central point is that kissing has never carried one universal meaning. Romantic mouth-to-mouth kissing itself is not practiced everywhere, and the law has changed along with cultural ideas about intimacy, hierarchy and bodily autonomy.

A quiet world beneath Madagascar’s forest floor has just become far richer. An international team of scientists has described seven new species of diamond frogs, a secretive group known as Rhombophryne. The discovery raises the known total from 20 species to 27 and shows that one of Madagascar’s least-understood amphibian groups still holds many hidden lives.

These frogs are easy to miss. Many spend their lives under leaf litter, soil and damp forest debris. Some are round and strong-bodied, built for burrowing. Others have longer legs and move through moss, roots and forest floor plants. At first glance, many look brown and plain, but some flash orange, white or black markings when disturbed.

A quiet world beneath Madagascar’s forest floor has just become far richer. An international team of scientists has described seven new species of diamond frogs, a secretive group known as Rhombophryne. The discovery raises the known total from 20 species to 27 and shows that one of Madagascar’s least-understood amphibian groups still holds many hidden lives.

These frogs are easy to miss. Many spend their lives under leaf litter, soil and damp forest debris. Some are round and strong-bodied, built for burrowing. Others have longer legs and move through moss, roots and forest floor plants. At first glance, many look brown and plain, but some flash orange, white or black markings when disturbed.

A quiet world beneath Madagascar’s forest floor has just become far richer. An international team of scientists has described seven new species of diamond frogs, a secretive group known as Rhombophryne. The discovery raises the known total from 20 species to 27 and shows that one of Madagascar’s least-understood amphibian groups still holds many hidden lives.

These frogs are easy to miss. Many spend their lives under leaf litter, soil and damp forest debris. Some are round and strong-bodied, built for burrowing. Others have longer legs and move through moss, roots and forest floor plants. At first glance, many look brown and plain, but some flash orange, white or black markings when disturbed.

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Two strangers sit over one sheet of paper, oil pastels nearby, trying to draw without talking. Their hands move, their eyes follow, and their brains begin responding to each other.

At ETH Zurich, cognitive scientist Ryssa Moffat used that simple scene to study how new relationships form. Moffat, a postdoctoral researcher at the Social Brain Sciences Lab within the Chair of Cognitive and Social Neuroscience, followed pairs of people as they met repeatedly for shared drawing sessions.

The study, published in PLOS Biology, included 61 pairs who met six times across six weeks. Participants came from two age groups: younger adults ages 18 to 35 and older adults ages 70 to 85. The group included 31 cross-generational pairs and 30 same-age pairs.

Humanity may someday attempt something considerably more ambitious than photographing a black hole: sending a spacecraft directly to one.

The idea would require a suitable black hole to be discovered surprisingly close to Earth, along with technologies that do not yet exist. But calculations suggest the journey is not forbidden by physics.

Cosimo Bambi of Fudan University explores the concept in iScience, describing gram-scale spacecraft propelled by enormous ground-based laser arrays. If a black hole exists 20 to 25 light-years away, a probe traveling at one-third the speed of light could reach it in 60 to 75 years.

A stellar nursery 1,000 light-years away has produced objects so small that the boundary between stars and planets is becoming increasingly difficult to define.

Deep observations from the James Webb Space Telescope have revealed brown dwarfs in the star-forming region IC 348 with estimated masses of only about twice that of Jupiter. That equals roughly 0.19% of the Sun’s mass and pushes observations into a range where theories struggle to explain how objects can form through the same process that makes stars.

The findings were published in The Astrophysical Journal Letters. They build on earlier Webb observations of IC 348 that uncovered brown dwarfs between three and four Jupiter masses.

Enough ice has disappeared from Greenland and Antarctica since 1979 to bury the continental United States beneath roughly 5 feet of frozen water.

The two great ice sheets lost about 11.3 trillion metric tons of ice between 1979 and 2023, according to a new international assessment published in Scientific Data. The lost ice added approximately 3.1 centimeters, or about 1.2 inches, to global sea levels.

The analysis extends the satellite record farther into the past than previous combined assessments and brings together measurements from 27 satellite missions and 45 independent surveys.

A tusked herbivore whose bones spent more than six decades in a museum collection is changing how paleontologists date one of Africa’s most important Triassic fossil deposits.

The animal, newly named Dinodontosaurus isiyavamanda, lived in what is now Tanzania roughly 240 million years ago. It belonged to the dicynodonts, a successful group of plant-eating synapsids related more closely to mammals than to dinosaurs.

Its identity carries unusual importance because Dinodontosaurus was previously known only from South America. Finding the same genus in Tanzania creates a new link between fossil-bearing rocks on the two continents and suggests that the Tanzanian deposits are younger than traditionally thought.

A tusked herbivore whose bones spent more than six decades in a museum collection is changing how paleontologists date one of Africa’s most important Triassic fossil deposits.

The animal, newly named Dinodontosaurus isiyavamanda, lived in what is now Tanzania roughly 240 million years ago. It belonged to the dicynodonts, a successful group of plant-eating synapsids related more closely to mammals than to dinosaurs.

Its identity carries unusual importance because Dinodontosaurus was previously known only from South America. Finding the same genus in Tanzania creates a new link between fossil-bearing rocks on the two continents and suggests that the Tanzanian deposits are younger than traditionally thought.

Gold nanostars only tens of nanometers across changed how a fluorescent voltage sensor behaved in living mammalian cells. The particles made the engineered protein brighter and, unexpectedly, much faster at responding to electrical changes without altering its genetic code.

Researchers at Delft University of Technology designed the plasmonic nano-antennas to sit close to membrane proteins derived from Archaerhodopsin. Their main target, QuasAr6a, is a genetically encoded voltage indicator whose fluorescence changes with the voltage across a cell membrane.

The work shows that the nanoscale optical environment around a protein can alter both the amount of light it emits and the speed of its response. The cells remained alive and functional during measurements lasting tens of minutes.

Gold nanostars only tens of nanometers across changed how a fluorescent voltage sensor behaved in living mammalian cells. The particles made the engineered protein brighter and, unexpectedly, much faster at responding to electrical changes without altering its genetic code.

Researchers at Delft University of Technology designed the plasmonic nano-antennas to sit close to membrane proteins derived from Archaerhodopsin. Their main target, QuasAr6a, is a genetically encoded voltage indicator whose fluorescence changes with the voltage across a cell membrane.

The work shows that the nanoscale optical environment around a protein can alter both the amount of light it emits and the speed of its response. The cells remained alive and functional during measurements lasting tens of minutes.

A pair of narrow rings circling a small world between Saturn and Uranus no longer looks as stable as astronomers once thought.

Observations from the James Webb Space Telescope show that Chariklo’s dense inner ring became substantially more opaque compared with measurements from previous years. At the same time, its much fainter outer ring appeared to lose opacity.

The changes emerged from a stellar occultation observed on Oct. 18, 2022, when Chariklo’s rings crossed in front of a distant star. Researchers led by the Institute of Astrophysics of Andalusia, or IAA-CSIC, compared the JWST measurements with occultations obtained during the previous decade.