The dung cannon fungus has what unique characteristic?
Many organisms have the ability to accelerate at astonishing rates. For example, some insects have jaws that can snap shut faster than a cheetah can run. However, in terms of sheer acceleration, “Pilobolus crystallinus”, also known as the dung cannon or hat thrower fungus, shoots out its spores even faster.
As the name suggests, dung cannons grow in manure. The fungus uses hydraulic pressure to “fire off” its spores, much like a squirt gun. The spores adhere to nearby vegetation, and are consumed by grazing animals. Safely making their way through the host animal's digestive system, they are eventually “deposited” elsewhere.
Back out, the fungus germinates within the feces, growing stalks called hyphae, which in turn grow and develop fluid-filled bulbs. The bulbs swell, becoming miniature cannons which fire off the spores when the pressure gets too great, propelling the spores away from the dung and starting the cycle all over again.
Amazingly, these fungi only grow to be 2–4 cm (0.8–1.6 in) tall, yet they can shoot their sporangium, (the structure within which spores are produced) over 2 meters (6.6 feet) away. The pressure is so extreme that the sporangium have been “clocked” going from zero to 72.4 kilometers (45 miles) per hour within the first millimeter (0.04 inches) of flight, which is the equivalent of an incredible 20,000 g‘s. That speed is comparable to a human being launched at 100 times the speed of sound, roughly twice the acceleration of a speeding bullet.