Archivo: Science
Dolphins learn the ‘names’ of their friends to form teams—a first in animal kingdom
Like members of a street gang, male dolphins summon their buddies when it comes time to raid and pillage—or, in their case, to capture and defend females in heat. A new study reveals they do this by learning the “names,” or signature whistles, of their closest allies—sometimes more than a dozen animals—and remembering who consistently cooperated with them in the past. The findings indicate dolphins have a concept of team membership—previously seen only in humans—and may help reveal how they maintain such intricate and tight-knit societies.
Just 19% of Earth’s land is still ‘wild,’ analysis suggests
Since the 1960s, conservationists have had a standard solution for saving biodiversity: Protect natural areas from human influence. But a new analysis of Earth’s land use going back 12,000 years suggests that even in the time of mammoths and giant sloths, just one-quarter of the planet was untouched by humans, compared with 19% today. Because some of those inhabited areas are now biodiversity hot spots, people probably helped sustain—and even increase—the diversity of other species for millennia, the authors write. The findings also suggest many traditional practices and Indigenous peoples play a key role in preserving biodiversity.
Vaccines that can protect against many coronaviruses could prevent another pandemic
In 2017, three leading vaccine researchers submitted a grant application with an ambitious goal. At the time, no one had proved a vaccine could stop even a single beta coronavirus—the notorious viral group then known to include the lethal agents of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), as well as several causes of the common cold and many bat viruses. But these researchers wanted to develop a vaccine against them all.
For The First Time, Scientists Have Performed Atom Interferometry in Space
To make some of the most precise measurements we can of the world around us, scientists tend to go small – right down to the atomic scale, using a technique called atom interferometry.
Nature’s most magnetic objects, ripped apart in starquakes, can unleash powerful flashes of light
On 15 April 2020, a wave of gamma rays, nature’s most powerful kind of light, washed across the Solar System like a storm front. First contact came above Mars, where photons at energies comparable to the radiation from a nuclear bomb peppered a Russian particle detector on NASA’s Mars Odyssey probe. Six minutes later, the burst of light lit up a solar wind probe between the Sun and Earth. Five seconds after that, the signal splashed into specialized detectors on Earth’s surface.
Hard choices emerge as link between AstraZeneca vaccine and rare clotting disorder becomes clearer
What was a worrisome suspicion four weeks ago is now widely accepted: The AstraZeneca COVID-19 vaccine can, in very rare cases, cause a disorder characterized by dangerous blood clots and low platelet counts. In Europe, at least 222 suspected cases have been reported among 34 million who have received their first dose of the vaccine. More than 30 have died.
Particle mystery deepens, as physicists confirm that the muon is more magnetic than predicted
A potential chink in physicists’ understanding of fundamental particles and forces now looks more real. New measurements confirm a fleeting subatomic particle called the muon may be ever so slightly more magnetic than theory predicts, a team of more than 200 physicists reported this week. That small anomaly—just 2.5 parts in 1 billion—is a welcome threat to particle physicists’ prevailing theory, the standard model, which has long explained pretty much everything they’ve seen at atom smashers and left them pining for something new to puzzle over.
Birds versus bees: Here are the winners and losers in the great pesticide trade-off
Farms are battlefields, pitting growers against rapacious pests and aggressive weeds in never-ending, costly campaigns that often involve chemical weapons. Those weapons, alas, also harm innocent bystanders such as bees, fish, and crustaceans. Now, a large study charts epic shifts that have occurred in recent decades as U.S. farmers have changed their arsenal of pesticides. Birds and mammals have fared much better, whereas pollinators and aquatic invertebrates are suffering. The toxic impact to land plants has also skyrocketed, likely because farmers are using increasing kinds of chemicals to fight weeds that have become resistant to common herbicides.
Earliest South American migrants had Indigenous Australian, Melanesian ancestry
In 2015, scientists discovered something surprising: that some Indigenous peoples in the Brazilian Amazon were distantly—but distinctly—related to native Australians and Melanesians. The genetic signal of Australasian ancestry in so far-flung a population sent researchers scrambling for answers. A new study reveals this genetic signal is more prevalent throughout South America than thought and suggests the people who first carried these genes into the New World got it from an ancestral Siberian population.
Dark matter could warm the hearts of lonely old planets, scientists predict
Dark matter might be raising the temperature of planets outside our Solar System, a pair of physicists predicts. Space telescopes already in the works should be able to spot the effect, they say, potentially enabling scientists to trace how the mysterious stuff is distributed within our Milky Way Galaxy.