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Babies born through the vaginal canal host different microbes compared with those delivered by c-section.Credit: mustafagull/Getty

Newborns delivered by caesarean section tend to lack strains of gut bacteria found in healthy children and adults. Instead, their guts harbour harmful microbes that are common in hospitals. That’s the finding of a study that examined nearly 600 births in the United Kingdom, the largest-ever study of the newborn microbiome. The difference was so stark, says microbiologist Trevor Lawley, that “I could take a sample from a child and tell you with a high-level of certainty how they were born.” But factors beyond the method of delivery — such as spending more time in the hospital afterwards — probably contribute, too, and it’s not clear how the differences affect a baby’s health.

Nature | 5 min read

Reference: Nature paper

US President Donald Trump’s administration wants to revoke California’s legal authority to set its own automobile-emissions standards for cars and trucks. Twelve other states, plus Washington DC, also use California’s rules, which are stricter than Trump’s proposals. The federal government says “one national standard will provide much-needed regulatory certainty”. But because vehicles produce so much of the United States’ greenhouse-gas output — about 29% — even small changes to the rules could make a big difference to overall emissions. California leaders have pledged to challenge the decision in court.

Nature | 4 min read

Brain tumour cells connect to neurons and form functional synapses that help the cancer to thrive. Three studies describe this startling capability in brain cancers called gliomas, as well as in some breast cancers that spread to the brain. It’s an extremely hostile environment for cancer cells inside our skulls, “but somehow the tumour cells manage to really adopt and co-opt the machinery there”, says brain cancer researcher Lisa Sevenich.

Nature | 4 min read

Reference: Nature paper 1, Nature paper 2 & Nature paper 3

FEATURES & OPINION

Source: Global Carbon Project

The world is reckoning with some troubling numbers that will ultimately determine whether it will be possible to avoid the rapidly approaching climate meltdown. Nature documents the scale of the challenge in an infographic-packed feature that explores energy use, carbon dioxide pollution and issues of climate justice.

Nature | 8 min read

Why Nature joined the Covering Climate Now initiative

Coral reefs cover only a tiny fraction of the ocean floor, but they support almost 30% of the world’s marine fish species — and roughly 400 million people depend on them for work, food and protection. Yet every single reef could be gone by 2070 if global heating continues on its current path. Six researchers describe in detail how a bolder, scaled-up approach to the stewardship of land and sea could save reefs much more effectively than desperate, piecemeal initiatives.

Nature | 10 min read

Astrophysicist Julián Alvarado Gómez says he fell a little bit in love with the star he studies, Iota Horologii, which is a bit like the Sun’s younger twin. The star became even more attractive when he learned that it might have been the model for the star in the video game Halo, which he used to play professionally. The delightful coincidence has fuelled his passion for understanding what younger stars can tell us about the Sun’s past.

Science News | 14 min read

The people who will be most affected by the climate policies we set now haven’t even been born yet — so the law struggles to protect their interests, notes law student Larissa Parker. She argues for a new legal framework that can establish accountability from one generation to the next.

The Economist | 6 min read

Parker’s essay won The Economist’s essay competition for people aged 16-25, which asked “What fundamental economic and political change, if any, is needed for an effective response to climate change?”