More than 70,000 species of fungi have been identified on Earth. We know that fungi are incredibly mobile through the use of airborne spores. But how such tiny particles can battle through the air to reach new locations has been hypothesized about for decades, without solid answers.
Now research in the laboratory of botanist Nicholas Money, at Miami University in Ohio, has documented cavitation: the long standing theory about what gives spores their speed. Proposed in the 1960’s, cavitation is when a fungi spore is attached to the top of a stalk by a water-filled bulb. When the fungus dries, the water in the bulb evaporates and this lowers the pressure between the stalk and the spore. The drop in pressure lead to the vaporization of water in surrounding cells, which as a gas then flood into the empty bulb. The influx of gas causes the bulb to billow out. The subsequent rapid change in shape is too much for the spore, which is flung into the air.
Researchers in Money’s laboratory were able to confirm that cavitation is the process by which spores become airborne by filming fungi with high speed cameras that capture as many as one million frames per second. Sorting through the frames, Money says that only 10 of those captured showed the cavitation process because it happens so quickly. Analysis of the footage demonstrated to the researchers that fungi launch their spores at very high speeds, up to 70mph within microseconds. The high speeds that fungi spores reach on launch, is what helps them travel so far.
According to the researchers, without the high speed camera technology they would not have been able to capture the images necessary to confirm the cavitation hypothesis. Fifty years in the making, this research may lead to further inquiries into fungi mobility, now that the mechanism fungi use to launch spores has been confirmed.
(via Popular Science)
