Science News Headlines . Electronic skin to give robots the human touch . Exta-curricular activities make children healthier and happier . Great white sharks may have helped drive megalodons to extinction . These dolphins may turn to corals for skin care Read more about these topics below. Electronic skin to give robots the human touch A new type of artificial skin could give robots “near-human levels” of touch sensitivity. Professor Ravinder Dahiya, from the University of Glasgow, is the lead researcher developing the electronic skin which could lead to robots and prosthetic limbs having near-human touch sensitivity. He is shown here in the picture with the electronic skin. The electronic skin, developed at the University of Glasgow, draws inspiration from the human nervous system. There are tiny electronic printed circuit boards in the skin. Part of the information is processed here itself, just as we “feel” things with our fingertips. This makes the processing faster so that the robot can react faster. “This research could be the basis for a more advanced electronic skin which enables robots capable of exploring and interacting with the world in new ways, or building prosthetic* limbs which are capable of near-human levels of touch sensitivity,” said research co-author Fengyuan Liu. The system involves a human-shaped robot hand coated in a flexible plastic material that contains a network of pressure sensors. When a sensor is touched, there is a change in its electrical resistance. This is designed to mimic* the way sensory nerve cells work in the human body. A circuit built into the skin acts as an artificial synapse* – where electrical impulses pass between nerve cells. The artificial synapse refines* the signal being sent from the pressure sensor, turning it into a spike of ­voltage*. The frequency of the voltage spikes varies according to the level of pressure applied to the skin. If the voltage spike hits a preset threshold*, it triggers a reaction. In this case, the robot hand will recoil* from a sharp jab. Which of our five senses do you think it would be most useful for scientists to replicate in robots? Exta-curricular activities make children healthier and happier In a new study by the University of South Australia (UniSA) and the SA Education Department, researchers found that children’s well-being improved when they participated in extra-curricular* activities. In addition, their well-being worsened when they spent time on social media or playing video games. The study analysed data from 61,759 school students in classes 4 to 9. It assessed the average number of days per week that children participated in after-school activities (typically from 3 PM to 6 PM). It measured these against wellbeing factors of happiness, sadness, worry, engagement*, perseverance*, optimism*, emotion regulation and life satisfaction. UniSA lead researcher Dr Rosa Virgara said the research highlighted a big need to encourage children to participate in activities other than TV, laptop or phone screens. Children who played games, learned an instrument or even just hung around with friends after school were more likely to feel happier and healthier than kids who are parked in front of a screen, they found. “Our study highlights how some out-of-school activities can boost children’s wellbeing, while others – particularly screens – can chip away at their mental and physical health,” she said. “Screens are a massive distraction for children of all ages. Whether children are gaming, watching TV or on social media, there’s something about all screens that’s damaging to their wellbeing.” Children also are sitting still while doing homework or reading, just like when they are watching screens. But Dr Virgara said that homework or reading activity had a positive impact. So it was more than just the lack of physical activity that was involved. She said the research showed even children who already reported feeling happy benefited from participating in after-school activities. “What this shows is that we need to find ways to encourage children of all ages and backgrounds to get involved in activities that keep them away from TV, computers and mobile devices,” she said. Do you agree? Great white sharks may have helped drive megalodons to extinction Ancient shark teeth suggest that megalodons (shown in this artist’s illustration) and great white sharks munched on the same types of marine mammals. For millions of years, megalodon sharks were top ocean predators — and then came the great whites. New analyses of teeth hint that competition for food from great white sharks may have pushed the megaladon giants toward extinction. Megalodons were one of the largest carnivores ever to live, growing to at least 14 meters. This giant began menacing the oceans around 23 million years ago. When — and why — it went extinct isn’t clear. The species may have lingered until about 2.6 million years ago. Or it may have vanished as early as 3.5 million years ago, right around the time that the great white shark /Carcharodon carcharias/ appeared. To figure out if the two sharks dined on similar food, the researchers turned to zinc, which has two main forms: zinc-66 and zinc-64. The relative abundances of those isotopes, preserved in tooth enamel, can indicate an animal’s position in a food web. Plants — and plant eaters — are relatively high in zinc-66. Higher up the food chain, that 66-to-64 ratio decreases. Scientists reconstructed shark feeding habits by analyzing zinc in the teeth of 20 living shark species and 13 extinct species, including megalodons. The analyses revealed that when and where megalodons and great whites overlapped, the sharks had similar ratios. This finding suggests that their diets overlapped too, say geoscientist Jeremy McCormack of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues. Still, that the sharks consumed similar prey isn’t proof they were in competition, the researchers say. And there are many factors that may have helped drive megalodons to extinction Those factors include ocean circulation changes, collapsing prey populations and competition for food with other ocean creatures, like orcas. Dolphins may turn to corals for skin care The picture shows an underwater image of an Indo-Pacific bottlenosed dolphin rubbing on coral on the seafloor.A new study suggests the dolphins may behave in this intriguing way to keep their skin healthy thanks to substances within the corals. On her deep-sea dives, wildlife biologist Angela Ziltener of the University of Zurich often noticed Indo-Pacific bottlenosed dolphins doing something intriguing. The dolphins (Tursiops aduncus) would line up to take turns brushing their bodies against corals or sea sponges lining the seafloor. After more than a decade as an “adopted” member of the pod — a status that let Ziltener get up close without disturbing the animals — she and her team may have figured out why the animals behave this way: The dolphins may use corals and sea sponges as their own private pharmacies. Ziltener captured video showing members of the pod using corals as if they were a bath brush, swimming through to rub various parts of their bodies. “It’s not like they’re fighting each other for the turn,” Ziltener says. “No, they wait and then they go through.” Other times, an individual dolphin will arrive at a patch of coral on its own. But the dolphins won’t buff their bodies against just any corals, Ziltener says. They’re picky, primarily rubbing up against specific types of corals such as gorgonian corals and leather corals, as well as a kind of sea sponge. Ziltener and colleagues analyzed one-centimeter slices taken from wild corals and sponges. The team identified 17 compounds overall, including 10 with antibacterial or antimicrobial activity. It’s possible that as the dolphins swim through the corals, the compounds help protect the animals from skin irritations or infections, says coauthor Gertrud Morlock, an analytical chemist at Justus Liebig University Giessen in Germany. Other animals, including chimpanzees, can self-medicate. Marine biologist Jeremy Kiszka of Florida International University in Miami says the new study convinces him that the dolphins are using corals and sea sponges for that purpose. But, he says, additional experiments are necessary to prove the link. Lab tests, for instance, could help identify the types of bacteria that the compounds might work against. Sources: University of Glasgow, Kids News , Science News