Robber flies never miss their mark

Despite being just the size of a rice grain, robber flies, which live all over the world, are champion predators. In field experiments, they can detect targets the size of sand grains from nearly two feet away — 100 times the fly’s body length — and intercept them in under half a second. They never miss their mark. Now a team led by scientists has started to unveil the secrets to the robber fly’s prowess.

Notably, the researchers observed a behaviour never before described in a flying animal: About 30 cm from its prey, the robber fly slows, turns slightly and brings itself in for a close catch, approaching its target from behind.

And whereas humans have a single lens in each eye, the robber fly has several thousand lenses per eye. In the centre of each eye, the researchers found, is a concentration of large, forward-pointing lenses. “They basically have permanent binoculars,” said Trevor Wardill, a research fellow at the University of Cambridge, UK.
Steph Yin

Universe’s very dusty beginnings
Scientists have detected the oldest space dust. The light from galaxy A2744_YD4 has been on its way to us for 13.2 billion years, since the universe was only 600 million years old. Even then, the dust held tiny samples of the heavier elements needed eventually to form planets, and us.
Dennis Overbye

Tragedy lays bare an undersea world
On March 8, 2014, Malaysia Airlines Flight MH370 vanished with 239 passengers and crew over the Indian Ocean, triggering a search that lasted nearly three years before it was called off. With undersea sonar, scientists created 3D maps of more than 1,00,000 square miles of seafloor while looking for wreckage. The maps reveal a region of startling topographical complexity, with such unique features as an oceanic plateau called Broken Ridge. Before Flight MH370’s disappearance, only 5% of the southeast Indian Ocean had been mapped.
Nicholas St Fleur

An enormous ravioli orbiting saturn?
NASA’s Cassini spacecraft took photographs last week of Pan, a diminutive moon of Saturn, with a diameter of about 20 miles, roughly the size of New York City. These are the clearest images ever seen of Pan, which is one of Saturn’s shepherd moons.
The verdict: It looks an awful lot like a floating ravioli, or maybe a wrinkled flying saucer. “I saw this picture, and I thought, that’s an artist’s conception,” said Carolyn C Porco, a visiting scholar at the University of California, Berkeley, USA, who leads Cassini’s imaging team. “Then I realised it was real.”
Kenneth Chang

In Europe’s ancient caves, humans told stories dot by dot
In 1884, Georges Seurat famously placed dots atop a canvas to create an image of park-goers lounging along the Seine river in France. The technique was known as pointillism, and it seemed so new at the time. But 38,000 years ago, people living inside caves in southwest France were doing something similar, archaeologists say. In Abri Cellier, a cave site in France’s Vezere Valley, a team recently discovered 16 limestone tablets left after a previous excavation.

Images of animals, including a woolly mammoth, were formed by a series of punctured dots and, in some cases, carved connecting lines. Similar images have been discovered in nearby caves in France and Spain.
Joanna Klein

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