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View of the rooting system of the ancient tree Archaeopteris at the Cairo fossil Forest site.

The spectacular root system of the ancient tree Archaeopteris “seems to reveal the beginning of the future of what forests will ultimately become”, says biologist William Stein.Charles Ver Straeten

Oldest fossil trees reveal the roots of forests

The earliest known fossilized trees have been discovered in an abandoned quarry in the United States. The trees were part of a vast forest that covered the area around New York state around 386 million years ago. Three types of tree were found, along with “spectacularly extensive root systems” that indicate the trees had evolved more modern characteristics than previously thought. The discovery is particularly exciting because it comes from a planetary turning point, the Devonian period, when the first forests appeared on Earth.

BBC | 3 min read

Reference: Current Biology paper

Science’s biggest breakthrough of the year

Science has picked its 2019 Breakthrough of the Year: the first-ever image of a black hole. Runners-up include the discovery of effective treatments for Ebola and evidence of life’s resurgence after the dinosaur-killing asteroid hit Earth. Science readers voted for the fabulous new fossil that allowed us to imagine the faces of our ancient Denisovan relations.

Science | Ten breakthroughs

Ancient-DNA scientist fired

The University of Adelaide has fired Alan Cooper, the high-profile leader of its Australian Centre for Ancient DNA, for “serious misconduct”. His dismissal follows allegations that Cooper bullied staff and students, and an investigation into the ‘culture’ of the centre. Cooper told Nature that he rejects the allegation that he was a bully.

Nature | 3 min read

Trump picks leaders for science agencies

Computer scientist Sethuraman ‘Panch’ Panchanathan has been selected by US President Donald Trump to be the next head of the National Science Foundation. The president also tapped Neil Jacobs, acting head of the National Oceanic and Atmospheric Administration, to run that agency, which Jacobs has temporarily led since February. Both nominees need to be confirmed by the Senate before they can take office.

Nature | 3 min read

Features & opinion

What to see in 2020

From ecovisionaries at the Royal Academy of Arts to a new film version of Dune, these are our picks for the science and culture events to enjoy in 2020. (Most are in the United Kingdom or the United States.)

Nature | 8 min read

Let go of your data

The phrase ‘data upon request’ has been annoying scientists since it caused a spat between Isaac Newton and John Flamsteed in 1695. But most materials scientists still don’t share their data, note computer scientist Natasha Noy and nanomaterials scientist Aleksandr Noy. They spell out how to make data in materials science discoverable, reliable and sustainable.

Nature Materials | 8 min read

How to ward off an AI reproducibility crisis

Spurred by her frustration with difficulties recreating results from other research teams, artificial-intelligence researcher Joelle Pineau is leading an effort to encourage others in the field to open up their code. “It’s true that with code, you press start and, for the most part, it should do the same thing every time,” says Pineau. “The challenge can be trying to reproduce a precise set of instructions in machine code from a paper.”

Nature | 4 min read

Podcast: Disentangling three bodies

The three-body problem, which has stumped scientists since the 1600s, now has a solution — of sorts. Astrophysicist Nicholas Stone explains how he got to his relatively simple statistical solution by giving up on the detailed orbits and getting right to the punchline of how the system ultimately and inevitably disintegrates. Plus: festive songs with science lyrics!

Nature | 32 min listen

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Image of the week

Depth-color coded projections of three stentors

Credit: Dr. Igor Siwanowicz

Stentors — or trumpet animalcules — are a group of single-celled freshwater protozoa. This image won second prize in the 2019 Nikon Small World Photomicrography Competition, and was captured at 40 times magnification by researcher Igor Siwanowicz at the Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Virginia.

See more of the year’s best science images, selected by Nature’s photo team.

Quote of the day

“I actually own more gadolinium than any other human.”

Physicist Mark Vagins, the co-inventor of a technique for detecting neutrinos with gadolinium, speaking at a Nature Reviews Physics symposium.

Read more: Gigantic Japanese detector prepares to catch neutrinos from supernovae (Nature, from February)