What is the oldest culture that exist today

But all civilizations, now and in the past, are products of gradual transformation that takes places over time.

Civilization are not the same as nations. lots of people will answer this question with china! because it exist as a state today. but all civilizations, now and in the past, are products of gradual transformation that takes places over time. that goes for any civilization, however you define it. chinese civilization have survived over time. but so has ROman and mesoptamian civilization. they are just less recognizable. the question is flawed in assuming civilizations to be coherently demarkable entities. they aren't!