Context‐Dependent Food Preferences and Comparative Decision‐Making in Slime Mold Physarella oblonga

ABSTRACT Slime molds, despite their unicellular nature, exhibit complex behaviors and problem‐solving abilities that have fascinated researchers. They are widely utilized as model organisms in behavioral studies. In this study, we examined the feeding preferences of the acellular slime mold Physarella oblonga when exposed to different yeast species as food sources. Our findings reveal significant preferences shown by P. oblonga for specific yeast strains. When Wickerhamomyces anomalus JYC2560 was another option, P. oblonga significantly favored Hanseniaspora osmophila JYC2504 ( p < 0.05). Similarly, when Kazachstania exigua JYC2539 was another choice, P. oblonga exhibited a significant preference for Dekkera bruxellensis JYC2592 ( p < 0.05). However, no significant preference was observed in other pair experiments. Further investigations highlighted variations in responses among different slime mold strains. Additionally, introducing a third yeast species as a decoy showed that P. oblonga preferred Hanseniaspora osmophila JYC2504 over Dekkera bruxellensis JYC2592 ( p < 0.001), indicating a decoy effect. The preference can be changed if different yeast strains are used as decoys. Notably, this effect persisted even when the decoy yeast was fed to the slime mold in advance of the choice experiment, suggesting memory retention in slime molds. These findings contribute to our understanding of the intricate interactions between slime molds and their environment, emphasizing the diverse responses observed across different strains.