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A Heliconius butterfly.Credit: Tim Zurowski/Shutterstock
The big butterfly genome
Every butterfly in the United States and Canada — 845 species — has now had its genome sequenced. Some researchers are hailing the study as a landmark in genomics because of the comprehensive survey will allow them to explore big questions in evolution, such as why some branches of the tree of life are so diverse. Although most of the genomes are low-quality ‘drafts’, comprising short stretches of DNA, the data are already hinting at how new species can arise from interbreeding.
Science funders gamble on grant lotteries
A growing number of research agencies looking to lighten the load of paperwork and reduce bias are turning to a simple solution: pulling winners out of a hat. Typically, funders screen applications to ensure they meet a minimum standard, then select projects at random until all the cash has been allocated. Application forms are shorter, and no time is spent agonizing over the ranking of lots of projects that are all worthy.
Humans placed in suspended animation
Doctors have placed humans in suspended animation for the first time, as part of a trial to save the lives of people who face imminent death from their injuries. The technique involves replacing all of a person’s blood with ice-cold saline, rapidly cooling them and causing their brain activity to stop — a condition that would normally be used to diagnose someone as being dead. Surgeons then have two hours to do their work before the person is warmed up and their heart restarted. Results from the trial, which is taking place at the University of Maryland Medical Center in Baltimore, have not yet been revealed.
Features & opinion

Comet 2I/Borisov appears as a fuzzy blue dot in a time-lapse sequence from the Hubble Space Telescope, which shows background stars as streaks.NASA/ESA/D. Jewitt (UCLA)/J. DePasquale (STScI)
They came from outer space
Researchers grapple with the meaning of Comet 2I/Borisov and 1I/‘Oumuamua — the first objects known to enter our Solar System from interstellar space. ‘Oumuamua whizzed past the Sun in 2017, and left astronomers boggled by its very un-comet-like small size and elongated shape. By contrast, Borisov — which makes its closest approach to the Sun next month — is much more familiar. “It’s been so much fun to see this suddenly crack open and watch a new field develop,” says planetary astronomer Michele Bannister.
PhD students say mentors must improve
Nearly one in four graduate students who responded to a Nature survey said they would change their supervisor if they could start their programme again. More than 6,300 people worldwide responded to our biennial PhD survey, and many raised the need for more one-to-one support and better career guidance.

The dream of open access is slipping away
Major victories for open access have led some advocates to conclude that their battle is almost won, writes journalist Richard Poynder. But, he argues, a splintered Internet, tense geopolitics and publishers moving to control data could see barriers re-erected around research papers and make a fair and equitable global system of scholarly communication impossible.
Richard Poynder personal blog | 4 min intro and the full 84-page PDF