Top 10 stories of 2018: Climate change, gene-edited babies, hidden craters and more

In 2018, we saw just how much power science has to make a real impact.

Science News’ top stories of the year include a literal impact — the hidden contours of what appears to be a massive crater created when a meteorite slammed into Greenland long ago. That discovery ranks among our Top 10 partly because it’s just cool, but also because it raises the tantalizing prospect of solving a scientific mystery: Did the impact kick the planet into a roughly 1,000-year cold snap, called the Younger Dryas, almost 13,000 years ago?
The mammoths and other species that died out by the end of that period didn’t see climate change coming. But we can. That’s why human-driven climate change is our top story of the year. The rising tide of attribution studies shows that climbing temperatures are already turning extreme events, such as Hurricane Florence, more extreme. This year’s barrage of climate reports gave us a clearer picture of how climate change will affect Earth in the near future — fueling wildfires, sparking heat waves, raising sea levels —and how human actions to curb warming can have an impact.

2018 is also the year a Chinese researcher made the startling claim that he had created the first babies to be born with an edited gene. The ensuing uproar over the controversial birth of twin girls in China, whose genes were allegedly tweaked to reduce their risk of contracting HIV, is sure to have a lasting impact on the future of gene-editing technology.

Two other genetics stories made our Top 10. Genetic genealogy is shaking up the field of forensics, ID’ing suspects in cold cases while raising privacy issues. And in a lab experiment, a gene drive — a genetic tool designed to be inherited by 100 percent of offspring — wiped out a population of mosquitoes. That feat ushers in the enticing but perilous possibility of both eliminating certain diseases and deliberately driving a species to extinction.

Other stories rounding out our Top 10 examine issues close to home (how to sort through conflicting advice about drinking alcohol) and very far away (tracing a high-energy neutrino back to its source in a distant galaxy). We’ll be watching these stories to see what happens in 2019 and beyond.
— Macon Morehouse, News Director
hurricane flooding
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Can half a degree save us?
This is the year we learned that the 2015 Paris Agreement on global warming won’t be enough to forestall significant impacts of climate change. And a new field of research explicitly attributed some extreme weather events to human-caused climate change. This one-two punch made it clear that climate change isn’t just something to worry about in the coming decades. It’s already here. FULL STORY
Jiankui He
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Gene-edited babies
A Chinese scientist surprised the world in late November by claiming he had created the first gene-edited babies. Many researchers and ethicists say implanting gene-edited embryos to create babies is premature and exposes the children to unnecessary health risks. Critics also fear the creation of “designer babies.” FULL STORY
Sacramento sheriff and Golden State killer
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Genealogy solves crimes
In 2018, criminal investigators in the United States embraced genetic genealogy, a forensic technique for tracking down suspects through their family trees, to solve decades-old cold cases and some fresh crimes. But this new type of DNA-based detective work has raised questions about genetic privacy and police procedures. FULL STORY
IceCube detector
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A neutrino’s distant source
Mysterious particles called neutrinos constantly barrel down on Earth from space. No one has known where, exactly, the highest-energy neutrinos come from. This year, scientists finally put a finger on one likely source: a brilliant cosmic beacon called a blazar. The discovery could kick-start a new field of astronomy that combines information gleaned from neutrinos and light. FULL STORY
Greenland crater illustration
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Impact crater unearthed
For three years, a team of scientists kept a big secret: They had discovered a giant crater-shaped depression buried beneath about a kilometer of ice in northwestern Greenland. In November, the researchers revealed their find to the world. The crater may have reignited a debate over a controversial hypothesis about a mysterious cold snap known as the Younger Dryas. FULL STORY
Anopheles gambiae mosquitoes
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The end of mosquitoes?
For the first time, humans have built a set of pushy, destructive genes that infiltrated small populations of mosquitoes and drove them to extinction. This test and other news from 2018 feed one of humankind’s most persistent dreams: wiping mosquitoes off the face of the Earth. FULL STORY
person covering wine glass
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Health risks of alcohol
For people who enjoy an occasional cocktail, 2018 was a sobering year. Headlines delivered the news with stone-cold certainty: Alcohol — in any amount — is bad for your health. “The safest level of drinking is none,” a group of scientists concluded. FULL STORY
Mars south pole
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Mars’ ice-covered lake
Researchers reported this year that they found a wide lake of standing liquid near the Red Planet’s south pole, buried beneath 1.5 kilometers of ice. The purported polar pool is the largest volume of liquid water ever claimed to currently exist on Mars, and has probably been around for a long time. Both of those features raise hopes that life could survive on Mars today. FULL STORY
Gert-Jan Oskam walking with crutches
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Progress against paralysis
Intensive rehabilitation paired with electric stimulation of the spinal cord allowed six paralyzed people to walk or take steps years after their injuries, three small studies published this year showed. More importantly, they show that the spinal cord can make a comeback. FULL STORY
painting on cave walls in Spain
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Origins of human smarts
Archaeological discoveries reported this year broadened the scope of what scientists know about Stone Age ingenuity. These finds move the roots of innovative behavior ever closer to the origins of the human genus. FULL STORY