Movement behavioral plasticity of benthic diatoms driven by optimal foraging

Abstract

Adaptive locomotion of living organisms contributes to their competitive abilities and 1 help maintain their fitness in diverse environments. To date, understanding of 2 searching behaviours and how microscale dynamics scale up to ecosystem-level 3 processes remain poorly understood in ecology. Here, we investigate the motion 4 patterns of the biofilm-inhabiting marine diatom Navicula arenaria var. rostellata at 5 the two-dimensional space. We report that individual Navicula cells display a novel 6 "rotational run-and-reversal" movement behaviour at different concentrations of 7 dissolved silicate (dSi). Using experimental measurements of the search behaviours, 8 we show that translation motions of cells can be predicted exactly with a universal 9 model-the generalized Langevin theoretical model. Both the experimental and 10 theoretical results reveal quantitative agreement with an optimal foraging strategy 11 and show that circular and reversal behaviours both contribute to comparable spatial 12 diffusion properties. Our modelling results suggest that the evolving movement 13 behaviours of diatom cells are driven by optimization of searching their physical 14 surroundings, and predicted behavioural parameters coincide with the experimental 15observations. These optimized movement behaviours are an evolutionarily stable 16 strategy to cope with environmental complexity.

Cooperative Motility, Force Generation and Mechanosensing in a Foraging Non-Photosynthetic Diatom

“…A related set of equations describe colony diffusivity of N . sing1 (Supplementary information) and the mixotrophic diatom Navicula 58 . Thus, periodic reversal combined with random turning is likely to be a general strategy used by raphid pennate diatoms to avoid immobilization after encountering an obstacle.…”

Cooperative motility, force generation and mechanosensing in a foraging non-photosynthetic diatom

“…A related set of equations describes colony diffusivity of N. sing1 (electronic supplementary material) and the mixotrophic diatom Navicula [ 72 ]. Thus, periodic reversal combined with random turning is likely to be a general strategy used by raphid pennate diatoms to avoid immobilization after encountering an obstacle.…”