TY - JOUR T1 - Optimal foraging of benthic diatoms evolving novel movement behaviours JF - bioRxiv DO - 10.1101/682153 SP - 682153 AU - Hu, Wen-Si AU - Huang, Ming-Ji AU - Zhang, He-Peng AU - Zhang, Feng AU - Vyverman, Wim AU - Liu, Quan-Xing Y1 - 2019/01/01 UR - http://biorxiv.org/content/early/2019/06/26/682153.abstract N2 - Adaptive locomotion of living organisms contributes to their competitive abilities and help maintain their fitness in diverse environments. To date, understanding of searching behaviours and how microscale dynamics scale up to ecosystem-level processes remain poorly understood in ecology. Here, we investigate the motion patterns of the biofilm-inhabiting marine diatom Navicula arenaria var. rostellata at the two-dimensional space. We report that individual Navicula cells display a novel “rotational run-and-reversal” movement behaviour at different concentrations of dissolved silicate (dSi). Using experimental measurements of the search behaviours, we show that translation motions of cells can be predicted exactly with a universal model—the generalized Langevin theoretical model. Both the experimental and theoretical results reveal quantitative agreement with an optimal foraging strategy and show that circular and reversal behaviours both contribute to comparable spatial diffusion properties. Our modelling results suggest that the evolving movement behaviours of diatom cells are driven by optimization of searching their physical surroundings, and predicted behavioural parameters coincide with the experimental observations. These optimized movement behaviours are an evolutionarily stable strategy to cope with environmental complexity.One sentence summary Contrary to wide belief, new experiments reveal that diatoms can active search food in their physical surroundings by adjusting movement behaviours. ER -