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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift
KentuckyFC writes "Many types of small spider release threads into the air which then lift and carry them significant distances. Biologists have found them at altitudes of up to 4 km. The conventional thinking is that the threads catch thermal air currents which then carry them away but this does not explain how spiders perform their trick even when there is little or no wind. Now one physicist says the explanation is the atmosphere's natural electric field which has an average downward-pointing magnitude of 120 Volts per metre. He calculates that a strand of silk need only gain a negative charge of around 30 nanoCoulombs to lift a spider. That explains how the spiders take off on windless days, how they reach such great heights and how several strands can lift heavier spiders of up to 100 milligrams."
"Of course, Gorham’s ideas will need to be tested by actually measuring the charge on gossamer spider silk as it is generated. That’s an experiment for an enterprising biologist to take on."
Some people die at 25 and aren't buried until 75. -Benjamin Franklin
I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.
Most "precisely engineered" stuff that's actually engineered is still the product of large quantities of trial and error, at some level :)
What if the intelligent designer just wanted to use evolution? I've never understood why the two solutions have to be exclusive.
"not as efficient?" These seem a whole lot more efficient than wings to me. A single one-time expenditure of energy and they go for miles. There are downsides to this method of course, most obviously that they don't have any control of where they go. But if you accept that limitation this seems to be a nearly optimal method of flight.