Hello Nature readers, would you like to get this Briefing in your inbox free every day? Sign up here.
A California two-spot octopus (Octopus bimaculoides) catches a fiddler crab (Leptuca pugilator), one of its favourite foods.Credit: Peter Kilian
How octopuses taste with their arms
Octopuses have an unusual way of enjoying their meals: chemical receptors on the suckers on their limbs allow them to taste by touching. On the surface of octopus tentacle cells, scientists found distinct tube-shaped structures — each made of 5 proteins, encoded by 26 genes, with millions of possible combinations — that bind to greasy molecules found in their food, on the sea floor and on their own eggs. The diversity of the structures might allow an octopus to work out what it’s tasting quickly, without sending the information to its brain.
Reference: Nature paper 1 & Nature paper 2
Enzyme slow-down puts brakes on ageing
One of the effects of ageing seems to be that it speeds up transcription — the process that produces RNA from a DNA blueprint — and causes careless copying errors. Researchers found the effect across five very different kinds of life (worms, fruit flies, mice, rats and humans). To test the impact on lifespan, researchers looked at fruit flies and worms with a mutation that slows down the transcription enzyme’s movement along the DNA strand and found that the animals lived longer than their non-mutant counterparts. When researchers used gene editing to reverse the mutation in worms, the creatures’ lifespans shortened. In human cells, boosting the levels of histones — proteins that DNA is wound around — also cut the enzyme’s pace.
‘Plastic rocks’ form in river
‘Plastic rocks’ made from thin films of plastic waste bonded to stones have been discovered in a freshwater creek in China. This is the first time scientists have found such waste to be chemically bonded to rocks, rather than just physically embedded in sediments, say the researchers. “People in the twentieth and twenty-first century are creating new geological records,” says soil scientist Deyi Hou. In lab tests, the rocks shed large amounts of polluting microplastics.
Reference: Environmental Science & Technology paper
Researchers have found sheets of plastic litter chemically bound to rocks sitting along a creek in China.Credit: Deyi Hou & Liuwei Wang/Tsinghua University
Features & opinion
After dark, the Arctic harbours hidden life
Researchers are braving cold and disorienting 24-hour darkness to unlock secrets of how marine organisms in the Arctic tell day from night during the polar winter. In 2007, a chance discovery challenged the conventional wisdom that polar marine ecosystems shut down throughout the months-long winter darkness. Now, scientists on board a trawler fishing near Norway’s Svalbard archipelago are testing ways to monitor ocean life in the Arctic night without altering its behaviour. Instruments such as the Fish Disco, which emits multicoloured flashes, help the researchers to understand how fish and plankton exploit darkness and moonlight — and how they are affected by ever-increasing light pollution.
Teach your students ChatGPT the right way
Instead of being banned from using large language model algorithms such as ChatGPT, students need to learn how to use them responsibly, says environmental scientist Hong Yang. In his air-pollution courses, students use ChatGPT to help them design a research project. He shares his tips for using chatbots productively in the classroom:
• Learn how to write good prompts and work with other lecturers and your students to refine them
• Use a range of assessment types, such as oral presentations, to avoid plagiarism
• Be aware that ChatGPT can worsen inequality by regurgitating biased or inaccurate information
• Define clear goals for what you want to achieve with ChatGPT
Can the US achieve its electric-car goals?
The US Environmental Protection Agency has proposed a landmark set of pollution regulations that could spark an electric-vehicle revolution in the United States. The agency will set pollution limits for new cars sold between 2027 and 2032. If the rules come into force, they could make a major dent in US carbon emissions. And analysts say that the legal viability, economic incentives and raw materials are all in place to make it happen.
Image of the week
The rings surrounding Uranus have been notoriously difficult for most telescopes to capture owing to their dark, dusty composition. Only the Voyager 2 Spacecraft and the Keck Observatory in Hawaii have caught a glimpse of the rings. Now, super-sensitive infrared sensors on the James Webb Space Telescope (JWST) have picked up 11 rings surrounding Uranus, along with its clouds and polar caps. “How amazing it is to see Uranus in the kind of detail that has only previously been possible by Voyager 2 actually visiting it,” says astronomer Michael Merrifield. (New Scientist | 3 min read) (NASA, ESA, CSA, STScI/J. DePasquale (STScI))
