Nosing around

The rules of hide and seek are very different underground. Down here, it’s more like murder in the dark. Artificial lights help us to see this hidden world, but those that live here have to feel their way. Instead of vision, imagine a life based on textures. Slimy worms and hairy grubs make a banquet for one predator. They stumble into its labyrinth of tunnels and now it comes to collect them. Nothing escapes its touch. Their moist soft bodies will give them away. This is the world of the most bizarre predator of all. The star-nosed mole. It sees the world through its nose - one square centimetre at a time. It reads the tunnel walls like a Braille map and in this soup of soil and roots it can pick out tiny worms and insects only millimetres across. In fact, this nose is just like an eye - except it sees in textures. And to see how it works we must enter the microscopic world. Twenty-two fleshy tentacles surround its nostrils. Each one is covered in thousands of tiny buttons - enough to touch a pin head in more than 600 places at once. When pressed, they pass a three dimensional picture of the soil to the brain. The central arms are especially sensitive, like an eye spot. They could detect a grain of salt in a pile of sand. An animal half a millimetre across is no problem. The outer arms detect, central arms confirm, the mouth eats. As it feeds the nose is positioned square to the floor. And the tamping action guides the eye-spot to any tasty tit-bits. Touch vision only works when the nose is in contact with the ground. It sees texture one frame at a time. It presses down and an impression is formed. It lifts its head and effectively goes blind. It changes position and down again. Prey is confirmed and it’s eaten. But watch how fast this really happens: it’s like reading a flicker book. As the mole moves it constructs a 3D model of its tunnel. Roots become pipelines... grains of sand, boulders. And tiny animals, spiky monsters. Spring-tails smaller than a match-head are covered in telltale hairs. So are soil mites. But this is the greatest prize of all - a mole banquet, a humble earthworm. Its segments and hooks advertise its presence like a textural neon sign, but the mole still has to touch it to see it. It misses the equivalent of a 30lb sausage. It turns. It's definitely worth fighting for.

Release date:

Duration:

5 minutes

Credits

Role Contributor
Editor-in-chiefPeter BASSETT
Editor-in-chiefDavid WALLACE
ProducerPeter BASSETT
NarratorJohn HANNAH

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