Nature reveals how spiders can use webbing to sail through the air… and then land on water and keep on sailing:
Morito Hayashi, a spider researcher at the Natural History Museum in London, says that it had been assumed that a wet landing would be deadly for what are known as ballooning spiders — those that drift to new habitats on wind-blown silken threads that they spin to lift themselves aloft.
But laboratory experiments by Hayashi and his colleagues, conducted at the University of Nottingham, UK, have shown that spiders can survive afloat, and can also harness the wind to ‘sail’ on the surface of water bodies. “Because 70% of our planet is covered by water, if they’re ballooning, they have to face landing on water,” says Hayashi.
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Their water-repellent legs kept them alive on both fresh and salt water in laboratory tests and allowed them to deal with waves up to 0.5 millimetres in height. When wind was simulated, a number of the spiders would raise their legs or abdomens to use as sails, propelling themselves across the water’s surface.
The spiders also dropped silk to anchor themselves in place while afloat. The animals did not show these behaviours on solid surfaces, suggesting that they are deliberate adaptations to water.