Spore-Flinging Fungi Set Flight Record

Sept. 17, 2008 -- Scientists have measured the fastest launch acceleration known in nature -- a tiny fungal spore that is squirted eight feet away from its home on a dung heap to greener pastures.

The researchers used very high-speed video capturing 250,000 frames per second to record the spore-flinging, which can't be seen with the naked eye because it happens in one-millionth of a second.

The recordings allowed them to calculate the acceleration, which ranged from 20,000 to 180,000 times the acceleration of gravity in the four fungal species tested.

"In terms of velocity, there are other things that move faster," said study lead author Nicholas Money of Miami University in Oxford, Ohio. "It's the acceleration here that's really astonishing. These microscopic spores are stationary, and one millionth of a second later, they are moving at 25 meters per second [56 miles per hour]."

Given the size of the spores, this acceleration would be equivalent to a person traveling at 5,000 times the speed of sound, Money said.

Because the spores are so tiny, air exerts a huge amount of drag on them -- imagine firing a cannonball through syrup -- so the spores need a lot of acceleration to overcome the slowdown.