Images used to compare observed patterns of macrofiber aggregates with theoretical randomly distributed populations. Two video frames representing an earlier and later stage of pattern formation are shown for each of three FJ7 populations: A 97-frame 86, B 97-frame 142, C 916-frame 150, D 916-frame 444, E 920-frame 125, F 920-frame 400. Each grid square = 30.25 mm2 of Petri dish surface. Bars = 10 mm. The filming rate was 1 frame/1.5 minutes.