Young Researchers Workshop: Current trends in kinetic theory

Brainless intelligence: the curious case of acellular slime mold Physarum polycephalum

Subash K. Ray

New Jersey Institute of Technology
[SLIDES]

In this talk, I will introduce a new model organism for studying complex, self-organized behavior in the lab – the acellular slime mold Physarum polycephalum. P. polycephalum is a large (up to several cm2), single-celled, multi-nucleated organism that moves in an amoeba-like fashion. The external membrane of P. polycephalum displays local contraction-relaxation patterns that are influenced by the quality of the local substrate. Relative differences between these patterns are responsible for the self-organized, dynamical distribution of the organism’s biomass, moving toward attractants and away for repellents, like a continuous swarm. These rhythmic contractions are believed to be responsible for the complex problem-solving abilities of P. polycephalum, such as finding the shortest path in mazes, building efficient tubules networks, anticipating periodic events, and making adaptive decisions when faced with complicated trade-offs between, for instance, food quality and foraging risk, speed and accuracy, and exploration and exploitation. Traditionally slime molds have been modelled as grids of interconnected tubules, without consideration for the spatiotemporal dynamic of the cell’s shape as it moves through its environment. Through this presentation, I hope to start a discussion with and seek insights from specialists of kinetic theory regarding developing new modeling approaches linking local density fluctuations of P. polycephalum’s membrane and the ability of this brainless organism to perform complex tasks.