Science And Sciencibility
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Sunday, 29 September 2024
This fish’s legs are made for walking — and tasting the sea floor
The northern sea robin (
Prionotus carolinus
) uses its six legs to stroll the ocean bottom and to taste the sea floor for buried prey. A detailed study of the unusual appendages has shed more light on how they help make the fish a spectacularly good hunter, and how
P. carolinus
repurposed its legs as sensory organs — as well as the evolutionary history of legs in the broader sea-robin family (Triglidae).
Saturday, 28 September 2024
Carbon bond that uses only one electron seen for first time
Scientists have observed a single-electron covalent bond between two carbon atoms for the first time. Researchers synthesized a molecule with a stable ‘shell’ of fused carbon rings that stretched out a carbon–carbon bond in its centre. The pull makes it susceptible to losing one electron in an oxidation reaction, leaving the elusive one-electron bond. With the new finding, the team hopes to better understand what defines a chemical bond in the first place.
Friday, 27 September 2024
Bacteria can invert gene sequences
Bacteria have the capacity to flip sequences of their genes from back to front, which can generate two different proteins from a gene. For example,
Bacteroides thetaiotaomicron
has a gene,
thiC
, that it can invert. One way round, it encodes for an enzyme needed to make the vitamin thiamine. The other way, it encodes a truncated protein. This ability seems to give the bacteria a survival advantage in different conditions. Researchers engineered bacteria that were ‘locked’ to either express the forward or the inverted version of
thiC
and examined the survival of the two populations of bacteria when grown at different concentrations of thiamine. Under conditions of low thiamine, bacteria that expressed the forward version of
thiC
dominated; when thiamine was high, the bacteria that expressed the inverted version of
thiC
had an advantage.
Wednesday, 25 September 2024
Octopuses and fish caught on camera hunting as a team
Octopuses and fish have been caught on camera teaming up to hunt for prey. Researchers caught 13 instances of the cross-species collaboration over 120 hours of footage, showing a big blue octopus (Octopus cyanea) working with different fish species to capture meals. Each of these scenes hinted at complex group dynamics, with different species adopting different roles.
Tuesday, 24 September 2024
Mathematicians discover new class of shape seen throughout nature
Mathematicians have described a new class of shape — soft cells. These shapes have corners that are deformed into thin points with internal angles of zero, which let them tessellate on a 2D plane with no gaps. Soft cells are common in nature, from the inside of onions to mollusc shells, but this new work is the first time they’ve been formally described.
Sunday, 22 September 2024
How cells swap instant messages
Cells in our bodies are passing delicate, time-sensitive notes to each other. These notes come in the form of messenger RNA (mRNA), which cells have to neatly package in sacs called vesicles to send between cells. This year, researchers showed that cells in all three domains of life - archaea, bacteria and eukaryotes - can send these messages, and even that they can be used as weapons between species. There are still questions to answer, such as whether other molecules packed into vesicles are necessary for mRNA’s message to land.
Saturday, 21 September 2024
Entangled quarks seen for first time
For the first time, scientists have observed quantum entanglement — a state in which particles intermingle and can’t be described separately — in fundamental particles called top quarks. Physicists had no reason to suspect that quarks wouldn’t allow themselves to be entangled, but researchers say this measurement, achieved by analysing over 1 million pairs of quarks created in collisions between protons, could pave the way for future high-energy tests of the phenomenon.
Friday, 20 September 2024
The crustaceans that smell their way home
Tiny crustaceans called mysids (
Hemimysis margalefi
) can use ‘smell’ to find their way back from the open sea to the caves where they live. When placed in Y-shaped containers in which one arm contains seawater from their home cave, the shrimp-like creatures tended to opt for the water they were used to. Researchers showed that water from each cave had a unique chemical signature, which they suspect the mysids are using to find their way back in low-light conditions.
Thursday, 19 September 2024
‘The standard model is not dead’: ultra-precise particle measurement thrills physicists
Researchers at CERN have calculated the mass of a fundamental particle called the W boson: 80,360.2 million electronvolts. The result quashes suggestions of a problem with the ‘standard model’ — physicists’ best description of particles and forces — raised by a discrepancy between the measured W boson mass and what the standard model predicts that was reported in 2022.
Wednesday, 18 September 2024
AlphaFold reveals how viruses evolved
Protein structures predicted by AI models have revealed some twists in the evolution of flaviviruses — a group that includes hepatitis C, dengue and Zika viruses. Researchers used DeepMind’s AlphaFold2 and Meta’s ESMFold to generate more than 33,000 predicted structures for proteins from 458 flavivirus species. They already uncovered some surprises. For example, the hepatitis C virus infects cells using an entry system similar to one seen in the pestiviruses — a group that includes animal pathogens like swine fever. Another big surprise was the discovery that some flaviviruses have an enzyme that seems to have been stolen from bacteria.
Friday, 13 September 2024
Rapa Nui’s population 'crash' debunked by ancient DNA
A study of ancient genomes has dispelled the theory that early inhabitants of Rapa Nui (also known as Easter Island) ravaged its ecosystem and caused the population to crash. Researchers analysed the DNA of ancient and modern Rapa Nui individuals and found no sign of a ‘population bottleneck’ that would have indicated a collapse. Genomes from ancient Rapa Nui people are predominantly of ancestries similar to those of other Pacific islanders, but around 10% of their genetic material can be traced to ancestors from coastal areas of what is now called South America. The findings suggest that Rapa Nui people made contact with people from these regions hundreds of years before Europeans first visited the island.
Wednesday, 11 September 2024
Marmosets use specific ‘names’ for one another
Marmosets use specific vocal labels to address other individual members of their species. When researchers separated pairs of marmosets with a barrier, they found that they used distinct ‘phee calls’ for the monkey on the other side. Besides humans, only dolphins and elephants have been recorded using similar labels for their fellow animals.
Friday, 6 September 2024
‘Nuclear clock’ breakthrough paves the way for super-precise timekeeping
Physicists have demonstrated all the ingredients of a nuclear clock — a device that keeps time by measuring tiny energy shifts inside an atomic nucleus. The breakthrough came from probing the nuclei of a rare isotope with a laser device called a frequency comb. Although the set-up isn’t technically a clock, because it hasn’t been used to measure time, “such impressive results make the development of a nuclear clock seem possible”, says atomic physicist Marianna Safronova. “It’s really one of the most exciting papers in recent times.”
Thursday, 5 September 2024
The biology of smell is a mystery — AI is helping to solve it
We smell by detecting molecules around us — but knowing the chemical structure of a molecule tells you almost nothing about its odour. Even categorising what we perceive is difficult: there is no palette of scent ‘primary colours’ as there is for vision. And olfactory receptor proteins are hard to work with, so what they look like and how they function has mostly been guesswork. But that isn’t stopping scientists from trying, with help from innovations in structural biology, data analytics and artificial intelligence.
Wednesday, 4 September 2024
An asteroid might have flipped Ganymede
Four billion years ago, Jupiter’s moon Ganymede might have been permanently turned by an asteroid 20 times bigger than the one that killed the dinosaurs. Researchers analysed distinctive furrows on the moon’s surface that point almost directly away from the gas giant. The furrows could be the remnants of a crater formed by an asteroid that was around 300 kilometres wide, say scientists. The impact might have turned Ganymede’s face away from Jupiter and reoriented its former far side towards the planet.
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