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Bumblebees bite plants to force them to flower

Bumble bee (Bombus terrestris) worker damages a plant leaf. Bee-inflicted leaf damage leads to accelerated flowering and might have implications for the phenological synchrony of plants and pollinators.Hannier Pulido, De Moraes and Mescher Laboratories

Bees: “feed me or I’ll cut you”

When pollen is scarce, bumblebees have their way of extorting more from plants. The insects bite into leaves with their mandibles and proboscises to induce flowering up to one month earlier than normal. Chemical ecologists spotted the unusual behaviour in Bombus terrestris during an unrelated laboratory experiment. Artificial cuts were not as effective, suggesting that some chemicals in the insects’ saliva could play a part. “This is one of those really rare studies that observes a natural phenomenon that hadn’t been documented before,” says ecologist John Mola.

Scientific American | 4 min read

Source: Science paper

Dashed hopes for African AI conference

An April meeting planned to be held in Addis Ababa, Ethiopia, would have been the first major artificial-intelligence (AI) conference in an African country — until coronavirus forced it to go virtual. The location of the annual International Conference on Learning Representations would have made it more accessible to researchers who cannot readily get visas to Western countries, and given Ethiopia a powerful opportunity to boost its research environment. “Africans and the institutions in Africa missed a chance to make connections and secure important collaborations,” says computer scientist Meareg Hailemariam.

Nature | 5 min read

COVID-19 coronavirus outbreak

A social distancing sticker is seen on an underground station platform

Measures aimed at slowing coronavirus spread are affecting other communicable diseases.Leon Neal/Getty

Lockdowns stopped flu in its tracks

Social-distancing measures aimed at slowing the spread of coronavirus seem to have shortened the influenza season in the northern hemisphere by about six weeks. A shorter flu season could spare tens of thousands of lives But the net impacts on global health will be hard to tease apart from the large number of deaths from COVID-19 as well as other causes in 2020 and beyond.

Nature | 4 min read

CDC muddies US testing numbers

The US Centers for Disease Control and Prevention (CDC)’s new dashboard was meant to offer the public insight into the progress of the country’s outbreak — now the biggest in the world. Instead, the agency has caused confusion by lumping together antibody tests along with tests for active COVID-19 infections. Several states are making the same mistake, reports The Atlantic. Testing is a crucial pillar of outbreak control, and mixing the two numbers — people who are not infected now, and people who probably haven’t been infected in the past — renders the statistic “uninterpretable”, says public-health researcher Ashish Jha.

The Atlantic | 8 min read

First book to tackle COVID-19 economics

Economist Joshua Gans has taken a brave shot at an impossible task: publishing the first book explaining the economic thinking that should guide policy in the time of COVID-19. With the situation and knowledge changing daily, the book is useful, but inevitably limited, says reviewer Philip Ball.

Nature | 6 min read

45%

The proportion of 200 million tweets about the coronavirus that were probably from fake accounts designed to sow disinformation, according to an as-yet-unpublished analysis. (NPR | 4 min read)

Features & opinion

Symbolic maths yields to neural networks

Deep learning lets computers work out statistical patterns in massive amounts of data. It is a more brute-force approach than symbolic AI, in which programmers encode explicit rules in their algorithms. Now, two computer scientists have shown that deep learning can handle mathematical symbols, too. Borrowing techniques from automated translation, they taught their neural networks to solve mathematical problems, such as integration. “Mathematicians will in general be very impressed if these techniques allow them to solve problems that people could not solve before,” says mathematician Anders Hansen. Some hope that a similar strategy could enable computers to find their own mathematical proofs.

Quanta | 8 min read

Source: arXiv preprint

Synthetic eye that ‘sees’ like a human

Electronic engineer Zhiyong Fan and his colleagues have built a biomimetic eye with a hemispherical retina made of perovskite nanowires. The shape gives the eye better image-sensing characteristics than a flat light sensor, and makes it appear more human. Electronic engineer Zhiyong Fan tells the Nature Podcast how he went from admiring robots on Star Trek to taking a step closer to making them a reality.

Nature Podcast | 22 min listen

Get the expert analysis from electronic engineer Hongrui Jiang in the Nature News & Views article.

Reference: Nature paper

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Where I work

Anne-Marie Coriat posing for a portrait by a bookshelf in the Wellcome Reading Room, London.

Anne-Marie Coriat is Wellcome’s head of UK and Europe Research Landscape in London.Credit: Leonora Saunders for Nature