Just recently in the last ten years they have found proof of the native tribes in both South America and North America having a culture of at least 26,000 years.
There are many different theories like you suggest. I think the most fun is the thirteen crystal skulls. It reads like the end of times set forth by the Bible and revelations.
I truly think in the end we are just afraid of death and would like to know what happens and explain it. All faiths are derived from this lack of "knowing".
Everything is based on superstitions and visions while in an altered state of consciousness. Visions, dreams, revelations,etc. all are based on fear.
Once fear is mastered, this becomes no more. The cycle you speak of may just be another prophesy of the unknown. We as superstitious humans tend to do this over and over throughout time.
My answer would be maybe, If we believe this to be possible. Then to us it could happen and be relevant to our future. It not, then why try to change something we cannot change.
In the end it is good to ask the questions of the unknown but do not allow your normal day and responsibilities to be influenced by the fear of possible death or these theories.
I get ran over by SUV's every other night in my dreams my friend. But then I work on the side of the freeway 24-7 in my line of work. My curse is to once again wake to do it all over again the next day for years on end.
But I would not trade it for anything.
If I disappear from a discussion please forgive me. My 24-7 business requires me to split mid-sentence to serve them. I am not ducking out, I will be back later to catch up.