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US President Donald Trump has said that remaining in the Paris climate agreement would hurt the country economically.Credit: Mark Wilson/Getty

The United States has officially announced its intention to withdraw from the 2015 Paris climate agreement. Way back in June 2017, President Donald Trump said he would take the country out, but yesterday was the earliest date the rules allowed it. The Trump administration argues that the agreement harms the country’s economic competitiveness, while critics say the United States is isolating itself from the global push towards a low-carbon economy. The actual withdrawal will happen in a year on 4 November 2020 — one day after the next US presidential election. If a pro-Paris candidate wins then, the country could be back in the pact in 30 days.

Nature | 3 min read

The genomes of Africans who were liberated from slave ships and taken to the remote island of St Helena are offering clues about their origins in Africa. Twenty partial genomes from those who died on St Helena reveal that they are most closely related to people living today in central Gabon and northern Angola, but gaps in present-day genome data from parts of Africa make it difficult to say for certain. None of the people were closely related, nor did they belong to a single African population, suggesting that they lived in a challenging multicultural setting.

Nature | 5 min read

Reference: bioRxiv paper

“It's literally people who are kidnapped in Africa, weeks before.” Read more about how the investigation of a 150-year-old burial site is helping to unlock the mysteries of one of humanity’s darkest chapters. (from 2016, 13 min read)

Source: A. Pearson et al. Infernal Traffic (Council for British Archaeology, 2011)

Features & opinion

Illustration by Señor Salme

“The history of science tells us that some of the toughest questions will be addressed not by being answered but by being replaced with better questions,” argues science writer Philip Ball. He lays out why research cannot fulfil its social contract and reach new horizons by advancing on the same footing into the future.

Nature | 11 min read

This is the last of a series of essays on the roots of today’s research system. Read why, on Nature’s 150th anniversary, we’re looking back to learn how to navigate the present.

In 1938, botanists Elzada Clover and Lois Jotter set out on the Colorado River to catalogue the Grand Canyon’s cacti. It was a journey considered too dangerous for almost anyone, let alone two women. They disagreed. “Just because the only other woman who ever attempted this trip was drowned,” said Jotter, “is no reason women have any more to fear than men.”

The Atavist | 42 min read

“It's time for the world to learn that Ebola was discovered by a Congolese,” says Joel Lamika, a colleague of physician Jean-Jacques Muyembe at the Congo National Institute for Biomedical Research in Kinshasa. Muyembe tells NPR how he first came across a mysterious illness in a hospital in central Congo, how he pioneered the first effective treatment against Ebola, and how he is fighting for the future of science in his country.

NPR | 8 min read