In a lab test, arachnids did preflight maneuvers when an electric field was switched on
Spiders may lack wings, but they aren’t confined to the ground. Under the right conditions, some spider species will climb to a high point, release silk strands to form a parachute, and float away on the breeze. Buoyed by air currents, they’ve been known to drift kilometers above Earth’s surface, and even to cross oceans to reach new habitats (SN: 2/4/17, p. 12).
Now, new research suggests air isn’t the only force behind this flight, called ballooning. Spiders can sense electrical charges in Earth’s atmosphere, and the forces exerted by these charges might be a cue for them to alight, researchers suggest July 5 in Current Biology. That invisible signal could help explain why spiders’ take-off timing seem a bit, well, flighty