I always saw the hormones that regulate our emotions as primitive forms of memory, older than neurons. So an organism can remain in a certain state for a while.
There is also the possibility that RNA is used for memory:
That was a great article! The last paragraph, however:
"By the way, Knuth is interested in these algorithms mainly for the interesting mathematical problems (...) not because they’re in any way efficient algorithms! "
Made me wonder, these kind of algorithms, where there is a lot of comparing and swapping of adjacent records might be more efficient on a tape-based architecture. Or an architecture with a lot of prefetch caching.
Here, in the Netherlands, towns get more similar. Mostly because all the shops are part of the same big chains, with the same cheap building style, and the same ways roads are upgraded.
Cities all have their own history, so there is more variation there.