> hallmark of civilization is right in the etymology -- the existence of cities.
That is not really the etymology of "civilisation" though. City and civilisation share etymological roots, but city is not the etymological origin of the world civilisation.
And of course then we just ask the question: what are cities? Do gopher, or prairie dog colonies count? (or are those just towns? :)) How about ant colonies or bee hives?
Clearly all of the above share some similarities with some human settlements. They also have important differences of course. So if we want to decide if there are other "civilisations" on Earth parallel with us, we have to be more precise with our definitions.
> city is not the etymological origin of the world civilisation
Civilisations are a subset of societies [1]. Urbanisation is commonly held as a divider between complex societies and full-blown civilisations.
> then we just ask the question: what are cities?
This is valid. I’d say the defining attribute is economies of scale. Ant colonies and bee hives demonstrate elements of this; the sum is greater than the whole.
Whether ants and bees form complex societies is less debatable, unless we reduce the terms to mean intricate where we begin enveloping colonies of trees and every social animal, potentially even just multicellular life, which while poetically pleasing isn’t useful.
Or a beehive. Bees moved into the basement window of my house and watching them go in and out it seemed to me that this single beehive had more departures and arrivals than all the commercial airports in the world put together.
If you look at the problem of "bee decline" from the viewpoint of the beekeeper where you are responsible for it you are responsible for a "city" of 50,000 insects that faces all kinds of threats from the inside and outside.
