Ancient DNA recovered from nearly 40 ancient skeletons in central Germany up to 7500 years old has been offered hints to the intricate prehistoric events that shaped modern European populations.

The study, published today in Nature Communications, offers a never seen before glimpse into a series of events including major migrations from both Western Europe and Eurasia, and signs of an unexplained genetic turnover about 4000-5000 years ago.

These changes were likely brought about by the speedy growth and the migration of some populations. The new study also confirms that people moving out from Turkey colonized Europe and ultimate reached Germany about 7,500 years ago.

"What is intriguing is that the genetic markers of this first pan-European culture, which was clearly very successful, were then suddenly replaced around 4,500 years ago, and we don't know why," study co-author Alan Cooper of the University of Adelaide Australian Center for Ancient DNA said in a statement. "Something major happened, and the hunt is now on to find out what that was."

For decades, researchers have wondered whether people, or just ideas, spread from the Middle East during the agricultural revolution that occurred after the Mesolithic period.

By studying the mutations, or changes, in mtDNA sequences, researchers are able to probe the maternal histories of different human populations. It has enabled them to build a "family tree" of maternal ancestry, and group different mtDNA lineages together based on shared mutations.