what do we know about the history/evolution of individual Hindu jati?

Factual Questions
1

any institution that exists today must have been created at some point, and possibly other similar institutions died out in recorded memory.

So, do historians know the details about the creation and development of at least some of the currently existing jatis? Let’s say what are the common reasons for the founding families of jati A back in 15th century or whatnot to separate themselves from their then current jati B to found the A one? Were there cases of deliberate partition of jatis? Do jatis get formally abolished or dissolved?

Does the process of jati evolution continue today or has the system now become more powerful through the modern means of communication and hence more static?

2

bump

3

Wiki has a fairly comprehensive article on it.What is it you’re asking that’s not answered in that article?

4

which section of the “comprehensive article” addresses my question?

It’s my understanding that if you ask a south Chinese lineage organization “where you guys came from”, you will get an (alleged) answer with (alleged) documents, biographies and similar to prove it. How about if we ask the jati the same question? “When did your group appear and under what circumstances?”