USING STRUCTURE-FROM-MOTION AND VIRTUAL REALITY TO CONSTRUCT AND ANALYZE MODELS OF MICROBIAL MAT MORPHOLOGY

Microbial communities have existed on Earth for the majority of the planet’s history, yet we cannot fully explain their formation and ecology, which is key to understanding microbialites. Mat morphology reflects a complex history of interactions among self-organization processes within a community and responses to surrounding environmental variables, such as nutrient availability. In spatial ecology, competitive interactions are predicted to produce regularly spaced structures, whereas mutualistic interactions are predicted to result in clustering. Pinnacles are discrete morphological structures common to many microbial communities, including those in Lake Vanda, Antarctica. Novel applications of structure-from-motion (SFM) and virtual reality (VR) were used to analyze statistics of pinnacle morphology and spatial patterning to test the relative strength of mutualism versus competition feedback mechanisms that may affect pinnacle spacing.

SFM techniques used videos of benthic microbial mat topography to create three-dimensional (3D) models of the microbial mats. KeckCAVES VR software enabled interaction with microbial mat models in 3D space without the visual distortion that occurs when looking at a 3D object on a 2D screen. Pinnacles at each site were isolated from the models to characterize their morphometrics and spatial distribution. Results thus far show that different sites have different morphologies and spatial patterns, reflecting a complex ecosystem with many factors influencing pinnacle spacing, including both mutualistic and competitive processes. For example, a site at a depth of 23.3 meters had clustered spacing, while a nearby site at a depth of 23.6 m showed random spacing. The two sites have similar depth and proximity, but contrasting spatial patterns suggest that pinnacle self-assembly is influenced by numerous environmental variables and can potentially vary along local environmental gradients. Further analysis will continue to untangle the diversity of variables influencing mat morphology, which can be expanded to better interpret ancient microbialite formation.