Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 6: Poster I

BP 6.33: Poster

Montag, 1. April 2019, 17:30–19:30, Poster B2

Scaling Emergency Response of Physarum polycephalum: On the verge of death — •Jonghyun Lee, Adrian Fessel, and Hans-Günther Döbereiner — Institut für Biophysik, Universität Bremen

Physarum polycephalum is a unique unicellular organism that displays a wide array of behavioural patterns and structures. Some of these behaviours, such as learning or having a memory, were previously thought to be associated with more evolved organisms. We explore the capabilities of this organism further, by fragmenting it into microscopic particles called microplasmodia.

Normally, microplasmodia fuse together to form one giant network, previously described as a percolation transition [1]. However, under starvation, these microplasmodia do not reconstitute as one body, but as multiple mesoplasmodia, referred to as satellites, that move away from their original spot [2]. We investigated how the initial conditions influence the outcome of the growth pattern, via maximum search area hypothesis based on optimal foraging theory.

We found that the initial distribution of microplasmodia is the main factor of satellite formation, and the scaling relationship can be derived to describe the number and the size of these fragments. We further refine the model by accounting for collisions and probabilities of fusion during satellite formation, which agrees well with experimental results. Therefore, our unicellular organism on the verge of death maximizes its search area.

[1] Fessel, A. et al. (2012), Physical Review Letters 109, 078103. [2] Lee, J. et al. (2018), Journal of Physics D: Applied Physics 51, 244002