Biovermiculations: Mathematical Modeling of Complex Biological and Physical Processes In Mazelike Biomats

Complex, maze-like or hieroglyphics-like patterns (dubbed “vermiculations”) on cave walls around the world have drawn attention from the caving community in the past but no cogent explanation of them has been offered (Hill & Forti, 1997). Visually prominent versions of this type of pattern were observed in a sulfuric acid cave in Tabasco, Mexico, and potentially attributed to the large amount of living biomass and biofilm contained in the material (Hose et al., 2000). These particular vermiculations have been named “biovermiculations” to reflect this large biological component. Our team has observed similar features in caves around the world, and in lavatubes, in mine adits, and even on the walls of Mayan ruins. This has resulted in questions about formation mechanisms for these structures that must explain occurrences both in caves and other surface and subsurface settings.

Using cellular automata modeling, we have mathematically produced patterns that present the same geometric appearance as the biovermiculations. Pattern variations can be created by altering various rules within the schema. We are comparing modeling results to real biovermiculations and attempting to infer processes, (physical, chemical, and biological), that may be producing these patterns in real systems based on the alterations in the rule structure. Details of laminar and turbulent flow, surface roughness, viscosity, intrinsic cellular reproductive geometries, and the percentage mix of particulates (e.g. clays or mineral particles) all appear to contribute to the patterns seen across a large number of occurrences. Underlying lithological or geochemical differences, and even some features of the biological systems (e.g. photosynthetic vs. heterotrophic or chemotrophic) do not appear to be the predominant controlling factors.

Beyond the immediate project, cellular automata modeling has the potential to be a valuable research tool to explain other phenomena associated with similar complex interactions of biological systems with physical and chemical processes.