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A fossil of Yilingia spiciformis and the track it left as it moved.Credit: Z. Chen et al./Nature

The fossil of a bizarre-looking worm-like creature — and the exceptionally rare remains of the trail it left behind — is revising our understanding of when and how animals evolved. The fossil formed some time between 551 million and 539 million years ago, in the Ediacaran period. It joins a growing body of evidence that challenges the idea that animal life on Earth burst onto the scene during the ‘Cambrian explosion’, which began about 539 million years ago.

Nature | 4 min read

New research shows that a small number of ‘zealot’ bots deployed on a social network can bias how people vote — or even quash consensus and lead to deadlock. Biologist Carl Bergstrom and technology researcher Joseph Bak-Coleman examine the “alarming” implications and note the real-world evidence of this effect in the voting patterns of US and European Union elections.

A Nature Editorial urges legislators and regulators to take note of this evidence that voters really can be manipulated in the digital age.

Nature News & Views | 6 min read and Nature Editorial | 3 min read

Reference: Nature paper

Figure 1 | Social-network structure affects voters’ perceptions. In these social networks, ten individuals favour orange and eight favour blue. Each individual has four reciprocal social connections. a, In this random network, eight individuals correctly infer from their contacts’ preferences that orange is more popular, eight infer a draw and only two incorrectly infer that blue is more popular. b, When individuals largely interact with like-minded individuals, filter bubbles arise in which all individuals believe that their party is the most popular. Voting gridlock is more likely in such situations, because no one recognizes a need to compromise. c, Stewart et al.1 describe ‘information gerrymandering’, in which the network structure skews voters’ perceptions about others’ preferences. Here, two-thirds of voters mistakenly infer that blue is more popular. This is because blue proponents strategically influence a small number of orange-preferring individuals, whereas orange proponents squander their influence on like-minded individuals who have exclusively orange-preferring contacts, or on blue-preferring individuals who have enough blue-preferring contacts to remain unswayed.

Researchers have evacuated Earth’s highest remaining tropical glacier — on Mount Huascarán in Peru — after local protesters accused them of being a front for a mining company. The scientists managed to take four ice cores, which they will use to understand the history and future of the shrinking glacier. Glaciologist Lonnie Thompson, who has been studying the ice fields of Peru since 1974, sympathizes with the community that is fighting for a place he also loves. “Glaciers are sacred places,” says Thompson. “If every mountain had a village that was trying to protect it, we wouldn’t have the environmental problems we have today.”

Nature | 5 min read

FEATURES & OPINION

Climate change, a wave of refugees and poor planning are draining precious aquifers in Jordan. An ambitious desalination project promises to bring enormous quantities of water from the Red Sea, but has stumbled under the weight of geopolitical issues in the region. A handful of scientists are scrambling to map Jordan’s remaining water and to predict future changes.

Nature | 12 min read

Comparative physiologist Jessica Meir raised 12 bar-headed geese as her own, taught them to fly and led them into a wind tunnel to help discover how the birds cope with flying over the Himalayas. Meir and her colleagues found that, despite the demands of flight, the birds’ metabolism slowed as the external oxygen dropped. Next for Meir: a trip to the International Space Station as a NASA astronaut later this month. “I’m finally paying my dues,” says Meir. “I’m going to be the one poked and prodded.”

The Washington Post | 7 min read

Reference: eLife paper

From the possible paths of a hurricane to economic predictions, uncertainty is everywhere — but it’s notoriously hard to communicate effectively. Data-visualization researcher Jessica Hullman takes a detailed look at the pros and cons of seven different ways to show uncertainty in your charts and graphs.

Scientific American | 5 min read