SNIPPETS

Seals rely on whiskers to sense size of objects

It is well known that harbour seals use their whiskers to detect water velocities and the wakes of moving objects, and that these abilities help in capturing prey. But now German researchers have shown that a seal can also discriminate size and shape using only its whiskers.

The scientists used four paddles of different shapes and sizes to generate wakes in an experimental box submerged in a tank. The seal, a 12-year-old named Henry, was blindfolded and headphones were placed over his ears.

He put his head into the tank to sense the size and shape of the paddle being used. The study was published in The Journal of Experimental Biology. When he successfully identified a size or shape by touching the paddle outside the box that corresponded to the one that had made the wake within, he was rewarded with a herring snack. The seal was eventually able to discriminate paddles differing in size by as little as 3.6 centimeters.

He was also able to distinguish shape – the flat from the cylindrical, the flat from the triangular and the flat from the undulated paddle. But he could not distinguish any other shape combinations. The senior author, Wolf Hanke, a postdoctoral researcher at Rostock University, said that Henry was very enthusiastic about his training, which suggests that the ability is something innate. “They’re made to do this,” Hanke said. “This strongly suggests that the seal can sense different species of fish. If the seal can avoid tracking fish that are too small or too big, this saves energy.”

Nicholas Bakalar
New York Times News Service


Wine for superconductivity

Now scientists from Japan have shown that alcoholic drinks such as red wine can also help induce superconductivity in metals.
They found that immersing pellets of an iron-based compound in heated alcoholic beverages for 24 hours greatly increased their superconducting ability.
Usually, iron-based compounds exhibit this property after being exposed to air but it takes a very long time.

The new method induced superconductivity in a day.

The iron-based compounds were immersed in red and white wine, beer, Japanese sake, shochu, and whisky. They were then heated to 70°C for 24 hours. Red wine induced the best superconducting properties.

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