Question

Why does the pilobolus use such an explosive method to disperse its spores??

Answer 1

So it does not land in the zone of repugnance, a zone which prevents the spores from being consumed by the cow. (zone of repugnance is a zone of which a cow will not eat grass, this explosive dispersal of spores will allow the spores to be eaten by a cow and later pooped out to grow into a beautiful fungus)

Answer 2

Pilobolus or also called as hat-thrower fungus are known for their explosive dispersal. Pilobolus species feed saprobically (living in an environment that is anaerobic, organic-rich matter) on the feces of grazing animals. This microorganism must pass through the grazing animals' digestive tract as part of their life cycle. Because animals avoid grazing near their excreta , this fungi uses a phototropic or light-following squirt-gun mechanism to spread their sporangia up to three meters away from their parent fungus and to the unpolluted vegetation. The ballistic dispersion can reach a speed of up to 90 km/hr. This is accomplished by the release of high-pressure fluids originating from the sporangiophore stalk following the rift of the conspicuous subsporangial vesicle.