c5eb2b51_Than_a_Roomba____IEEE_Spectrum__ROOMBA
[SLIME MOLD] Slime mold has a memory for its external environment that rivals those of some robots, researchers at the University of Sydney found this summer. As it oozes around, Physarum consumes food, so covering the same ground twice would be a waste of energy. By reading the chemical cues in its own slime, or slime left by other slime mold, it can avoid areas that have already been depleted of tasty rotten leaves. This skill is comparable to what’s known as externalized spatial memory in a robot. [ROOMBA] 
Roomba has no memory of what your living room looks like. Every time it starts up, it’s starting over. Of course, this is exactly what it was designed to do. It would be possible to build a Roomba that remembers, but that would require more internal memory and processing power.
Is Slime Mold Smarter Than a Roomba? - IEEE Spectrum
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