Scientists have found that spiders use electricity to fly through the air!
Scientists would observe spiders climb to an exposed point, raise their abdomens to the sky, extrude strands of silk, and float away, a behavior called ballooning.
For centuries scientists marveled how spiders get airborne, as some spiders have been found two-and-a-half miles up in the air, and 1,000 miles out to sea.
But new discoveries have found that spiders can sense the Earth’s electric field, and use it to launch themselves into the air!
Every day, around 40,000 thunderstorms crackle around the world, collectively turning Earth’s atmosphere into a giant electrical circuit. The upper reaches of the atmosphere have a positive charge, and the planet’s surface has a negative one. Ballooning spiders operate within this planetary electric field.
When their silk leaves their bodies, it typically picks up a negative charge. This repels the similar negative charges on the surfaces on which the spiders sit, creating enough force to lift them into the air!
Dr. Erica Morley and Dr. Daniel Robert, from the University of Bristol, have tested this with actual spiders.
First, they showed that spiders can detect electric fields. They put them on vertical strips of cardboard in the center of a plastic box and then generated electric fields between the floor and ceiling of similar strengths to what the spiders would experience outdoors. These fields ruffled tiny sensory hairs on the spiders’ feet, known as trichobothria.
In response, the spiders performed a set of movements called tiptoeing—they stood on the ends of their legs and stuck their abdomens in the air. “That behavior is only ever seen before ballooning,” says Morley. Many of the spiders actually managed to take off, despite being in closed boxes with no airflow within them. And when Morley turned off the electric fields inside the boxes, the ballooning spiders dropped.
Nature never fails to impress.
Read more here.
In Other News
These Macaws Help Grow The Forest Around Them
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- Researchers used direct observation and camera traps to record more than 1,700 fruit dispersal events by the two macaw species.
- The study’s results challenge previously held views that the dispersal of large seeds was carried out by the now-extinct megafauna of the Pleistocene Epoch.
- Read more here.
The Kelps Are Alright: Studies Reveal Resilience in Kelp Forests
Kelps are large seaweeds that can grow up to 80 meters (260 feet) in length and live near the shore in cold-water marine habitats throughout the world. Kelp forests are among the world’s most productive ecosystems, are foundational to many fish and marine communities, and help to protect coasts from wave damage.
- Nearly half a century since they were first formally surveyed (in 1973), the kelp forests of Tierra del Fuego in South America remain relatively unchanged.
- Like many marine ecosystems, kelp forests are sensitive to local human stressors such as overfishing, pollution and coastal development, as well as sedimentation, overfishing and marine heatwaves.
- Re-examining the remote kelp forests of Tierra del Fuego, where there is a distinct lack of direct human impact, gives us a better understanding of the processes accounting for their resilience.
- “In this case, we identified an ecosystem that is resilient in the face of the global biodiversity crisis,” Friedlander said. “It is surprising and encouraging to see a place that has remained virtually unchanged in the 45 years since it was last studied.”
Wave-Powered Ferry Forging A New Path For Cargo Ships
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- The Philippines’ transport sector is the second-biggest contributor to the country’s greenhouse gas emissions, thanks to a large fleet of aging ships burning dirty fuel.
- The multi-hull boat now being built is expected to move more efficiently on the sea, cut average travel times by half, and have a lower carbon footprint!