"Adam" our most common male ancestor lived about 209,000 years ago, about 9000 years earlier than current estimates, according to a new study.

The study, conducted by Dr Eran Elhaik from the University of Sheffield and Dr Dan Graur from the University of Houston, shows that Adam lived in the same time frame as "Eve"- the genetic maternal ancestor of humans. Researchers reported using conventional biological models for their study. 

Adam and Eve                                                                                                           

Mitochondrial Eve and Y-chromosomal Adam are the most recent common ancestors, or MRCAs. It is widely believed that a vast majority of humans can trace back their ancestry to these two individuals. However, origin and evolution of Adam and Eve or even whether these two lived at the same time in history is still a mystery.

Previously, University of Arizona researchers and their colleagues had reported Adam to be much older than Eve. Their study had shown that the hereditary factor for determining the male sex- the Y chromosome- was present 338,000 years ago, much before the evolution of humans.

The present research also challenges the idea that the male chromosome originated in ancient species and humans inherited the chromosome via inbreeding.

"It is obvious that modern humans did not interbreed with hominins living over 500,000 years ago. It is also clear that there was no single 'Adam' and 'Eve' but rather groups of 'Adams and 'Eves' living side by side and wandering together in our world," Dr Elhaik said in a news release.

Elhaik said that the idea that Y-chromosome appeared before humans lacks scientific merit. "In fact, their hypothesis (University of Arizona's) creates a sort of 'space-time paradox 'whereby the most ancient individual belonging to Homo sapiens species has not yet been born. If we take the numerical results from previous studies seriously we can conclude that the past may be altered by the mother of 'Adam' deciding not to conceive him in the future, thus, bringing a retroactive end to our species," he added.

Recently, Stanford University School of Medicine researchers had said that Adam and Eve might have lived during the same time frame with Adam living somewhere between 120,000 and 156,000 years ago, and Eve living around 99,000 to 148,000 years ago.

The study is published in the European Journal of Human Genetics.

Debunking other research

This isn't the first time that Dr Elhaik is in news for debunking other researches. Previously, he had said that Jews trace their ancestry to a group of people from Europe, and not the Middle-East. However, many researchers, including Marcus Feldman a leading researcher in Jewish, had called it a "one-off paper." 

Elhaik and colleagues have also challenged results of the ENCODE project on junk DNA.