- hat-throwing fungus Pilobolus crystallinus
- 0 to 20 in 2 microseconds kilometre(s) per hour
- Not Applicable ()
The world's fastest-accelerating organism is the hat-throwing fungus Pilobolus crystallinus, native to Eurasia, North America and Australia. It grows in animal dung, where its asexual fruiting structure (the sporangiophore) is a stalk that resembles a tiny translucent snake bearing at its distal end what looks like a rimless black bowler hat but is actually its sporangium (a sac of spores). When they are mature, a massive increase in internal turgor pressure causes the sporangiophore to "throw" its hat-shaped sporangium with an acceleration of 0 to 20 km/h in only 2 μs, thus subjecting it to over 20,000 G. This is equivalent to a human being launched at 100 times the speed of sound, and is faster than a speeding bullet. The sporangium can travel up to 2 m away from the sporangiophore that launched it, and increases the chance that it will attach to vegetation that will be eaten by an animal through whose gut the sporangium will travel without being digested and then be excreted in its dung, whereupon the spores will be released and germinate in the dung.
Interestingly, some parasitic worms harness the hat-throwing fungus's remarkable activity as a means of bringing themselves into contact with potential animal hosts. They do this by attaching themselves as larvae to the sporangium before it is thrown, so that when it is thrown the worms are distributed with it and eaten by whatever eats the sporangium, and once inside their new hosts they can then mature into adult worms.