I've come across the philosophical debate about "universals" versus "particulars". On the one hand, some believe there are no universals, only particulars (nominalists). On the other hand, there are those who believe there are universals (realists). My question refers probably to the latter, but perhaps with implication to the former.
Example 1: markets.
Markets are studied by economists (among others). Economics assume there is some fundamental property of markets, which allows them to use that word as a category, and study them abstractly.
Now, markets didn't exist 1 million years ago (just to give a safe date). Yet, now they exist. What does this imply for the "universal" of markets? Did this universal come to being at some point in time? If so, can "universals" be created? (naturally, if there was void before the universe existed, then all universals are by definition created. This is particularly true in Christian versions of realism, e.g. Aquinas).
Example 2: cats.
Universals here would refer to the "catness" present in cats. Yet, because of evolution (which, to avoid unnecessary controversies, let us assume to be true), at some points further back in time there were no cats. Thus, what we call "cats" is rather a frame in a long process of evolution. In that respect, can "universals" evolve?
Any help is appreciated (even better if provides references for further reading).