'Ballooning' spiders take flight on Earth's electric fields

Research shows how arachnids' sense of atmospheric electricity allows it to spin a line and take off

We humans are only aware of the Earth's electrical field on stormy days, when the positively charged sky makes a circuit with the negatively charged Earth and lightning flashes between them. Spiders have a more nuanced sense of atmospheric electricity, and can harness it to take flight.

Research from the University of Bristol sheds light on ballooning", in which a spider holds on to a single strand of thread that carries them aloft. This feat was always assumed to be a matter of riding air currents by some unknown mechanism; Darwin was puzzled by aeronaut spiders" reaching the Beagle on gossamer threads 60 miles off South America. Since 2013 researchers have believed electric fields are involved - now they have observed the effect experimentally.