I found this research fascinating. Phys.org: Researchers find a single-celled slime mold with no nervous system that remembers food locations. https://phys.org/news/2021-02-single-celled-slime-mold-nervous-food.html
I enjoyed reading the article you recommended on the website above. You could spend hours reading. Searching phys.org is all it takes to get started.
Totally agree Margot, it is an amazing and very informative website. I always get excited when a new one pops into my in box.