Fungal spores can attach themselves to bacteria, "hitching a ride" wherever the bacteria travel. And while this allows them to travel further than they would on their own, says Prof. Eshel Ben-Jacob of TAU's Raymond and Beverly Sackler School of Physics and Astronomy, it's certainly not a one-way street. Bacteria live largely in the rhizosphere - the environment that surrounds plant roots - where air pockets can interrupt their progress, he explains. When faced with a gap, the bacteria can drop the fungal spores to form a bridge, and continue across the chasm.
PNAS - "Mutually facilitated dispersal between the nonmotile fungus Aspergillus fumigatus and the swarming bacterium Paenibacillus vortex " (http://www.pnas.org/content/early/2011/11/16/1102097108.abstract?sid=9488c9ca-89a7-40c0-8a76-3dce473b659c)
