From an octopus that learns to read a mirror to a seven-hour hunt for alien signals, this week’s science spans the deep ocean, the human body and the edge of the Solar System. Here are six discoveries that show how researchers keep finding the unexpected in places we thought we understood. Read on for the highlights, with a discussion question for each to use in class or at home.
1. Octopuses learn to use mirrors to find hidden food
Researchers at Dartmouth have shown that octopuses can learn to use a mirror as a tool, working out where food is hidden behind them rather than simply attacking their own reflection. Three California two-spot octopuses were trained until they understood the link between a reflection and the real world, then tested with a virtual crab that was only visible in the mirror. To win a reward, each animal had to turn around and move to the correct side. They chose correctly about 73% of the time. This is the first time the skill has been seen in an invertebrate; until now it was known only in some mammals and birds. What makes it remarkable is that our last common ancestor with octopuses was a worm that lived 350 to 500 million years ago, so this intelligence evolved completely independently from our own, an example of convergent evolution. The researchers suspect octopuses may even build an internal “map” of their surroundings to help them hunt.
Think About It: If an octopus and a human evolved mirror-using ability separately, does that tell us the skill is somehow useful in many environments, or just a lucky coincidence? How could you test the difference?
Image credit: Mary Kieseler / Dartmouth College — view source image
Originally reported by: ScienceDaily (Dartmouth College)
2. Seven-hour search for alien signals from interstellar visitor 3I/ATLAS
3I/ATLAS is only the third object ever confirmed to have come from another star system, after ‘Oumuamua and Borisov. With a rare visitor passing through, scientists at the SETI Institute pointed the Allen Telescope Array at it and listened for more than seven hours across radio frequencies from 1 to 9 gigahertz, searching for “technosignatures” — narrow radio signals that nature does not produce but technology does. The scan picked up nearly 74 million candidate signals. After filtering out interference from Earth and our own satellites, about 200 remained, and every one traced back to human technology. No aliens, then, which fits other evidence that 3I/ATLAS is a perfectly natural comet. The result still matters: it rules out any transmitter stronger than about 10 to 110 watts (roughly a household appliance) on or near the object, and shows astronomers can respond to a new interstellar visitor within a day of its discovery.
Think About It: Why is it scientifically valuable to search an object for alien signals even when researchers strongly expect to find none?
Image credit: Seth Shostak / SETI Institute — view source image
Originally reported by: SETI Institute
3. AI-designed universal coronavirus vaccine passes its first human trial
A vaccine whose active ingredient was designed entirely by computer has passed its first human safety trial, a first for the technology. Developed by the University of Cambridge and the spinout company DIOSynVax, it was tested in 39 healthy volunteers in Cambridge and Southampton and caused no significant side effects. Instead of targeting one strain, researchers used artificial intelligence to study the genetic make-up of a whole family of coronaviruses — including the virus behind COVID-19, the original SARS virus, and related bat viruses — and combined the features they share into a single “super-antigen.” The aim is protection that holds up even as viruses mutate, breaking the cycle of constantly updating vaccines to chase new variants. In this trial it was given needle-free, as a DNA vaccine fired in by a fine fluid jet. Larger trials are planned, and the team believes the same AI approach could be aimed at influenza and Ebola viruses too.
Think About It: A traditional flu jab is updated every year. What are the advantages, and the possible risks, of instead designing one vaccine meant to cover an entire virus family at once?
Image credit: University of Cambridge — view source image
Originally reported by: ScienceDaily (University of Cambridge)
4. A hidden quantum world found inside cobalt
Cobalt has been one of the most studied magnetic metals for forty years, so scientists assumed there was little left to learn. An international team led by Helmholtz-Zentrum Berlin has proved otherwise. Using a powerful technique at the BESSY II synchrotron, they found that cobalt contains a dense network of “magnetic nodal lines” — special crossing points in its electronic structure where electrons can behave like massless particles and travel extremely fast, similar to light. Crucially, these states survive at room temperature, not just in the deep cold that many quantum effects require. Even better, because cobalt is magnetic, the behaviour can be switched and controlled simply by changing the direction of its magnetic field — exactly the kind of on/off control engineers want for future “spintronic” devices that use electron spin as well as charge. The discovery hints that other familiar metals may hide similar surprises.
Think About It: Cobalt was thought to be fully understood, yet a new instrument revealed something new. What does this tell us about the role that improved measurement tools play in scientific discovery?
Image credit: Shutterstock (via ScienceDaily) — view source image
Originally reported by: ScienceDaily (Helmholtz-Zentrum Berlin)
5. South Australia’s koala boom could end in mass starvation
While koalas are in steep decline across much of eastern Australia, the opposite is happening in South Australia’s Mount Lofty Ranges, and researchers warn it is not the good news it appears to be. A new study estimates this single region now holds about 10% of all of Australia’s koalas, with densities far higher than the forests can support. If nothing changes, numbers could rise another 17% to 25% over the next 25 years, stripping the eucalyptus trees the animals depend on and risking a collapse into mass starvation. Culling and relocation are either controversial or unsuitable for such an iconic animal, so the team used computer modelling to test alternatives. Their most effective and humane option was targeted fertility control: sterilising about 22% of adult females each year in the most crowded areas, at an estimated cost of $34 million over 25 years. It is a striking reminder that “too many” of a beloved species can be as serious a conservation problem as “too few.”
Think About It: Managing an overabundant but much-loved animal raises both ecological and ethical questions. How should scientists and the public weigh animal welfare against the health of the whole ecosystem?
Image credit: Professor Corey Bradshaw, Flinders University — view source image
Originally reported by: ScienceDaily (University of Technology Sydney)
6. Weight-loss drugs like Ozempic linked to lower breast cancer risk
A large study from the University of Pennsylvania has found that women taking GLP-1 medications — the drug class that includes Ozempic, Wegovy, Mounjaro and Zepbound — were around 30% less likely to develop breast cancer. Researchers reviewed health records from more than 110,000 women aged 45 to 80, and the effect held up even after carefully matching users and non-users for factors like age, weight and breast density. GLP-1 drugs mimic a natural appetite-regulating hormone and were designed for diabetes and weight loss, so a possible cancer benefit was a surprise. Part of it may come from weight loss itself, since excess weight is a known risk factor, but the drugs also reduce inflammation and affect how genes are switched on and off, which could play a role. Importantly, this was an observational study: it shows a link, not proof of cause. A proper clinical trial is now being planned to test whether the drugs can genuinely help prevent breast cancer.
Think About It: This study found a strong link but cannot prove the drugs cause the lower cancer risk. Why is the difference between “correlation” and “causation” so important in medicine?
Image credit: Shutterstock (via ScienceDaily) — view source image
Originally reported by: ScienceDaily (University of Pennsylvania School of Medicine)
From clever cephalopods to careful caution about cancer, this week’s stories all share a theme: science keeps overturning what we thought was settled. Which of these surprised you most? Share this roundup with a curious friend or colleague, and let us know in the comments which story you would most like us to explore in more depth.
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