The concept of "zero" was not born in a single moment of revelation but evolved independently in several ancient cultures.
Why before "evolved" we don't put "it"? Because I was thinking it should be "it was not born" parallel with "it evolved"... If without "it", sounds like "was evolved"...? Where was I wrong?
The subject of "was not born" and "evolved" is the same (the concept of "zero"), so there's no need to repeat it. "Evolve" is an action, its' "to slowly become something different, yet of the same species". Since the verb is intransitive, you won't find it in the passive form. The meaning here is that several ancient cultures pondered about that concept, refined it, used it in different new fields