The studies delve into phylogenetics, a forensic hunt through the Xs and Ys of our chromosomes to find the genetic “Adam,” to borrow the name from the Bible. And Eran Elhaik from the University of Sheffield says he knows exactly when that first man lived.

“We can say with some certainty that modern humans emerged in Africa a little over 200,000 years ago,” Elhaik said in a press release. That directly contradicts a March 2013 study from Arizona Research Labs at the University of Arizona, which found that the human Y chromosome (the hereditary factor determining male sex) originated through interbreeding among species and dates back even further than 200 millennia.

“Our analysis indicates this lineage diverged from previously known Y chromosomes about 338,000 years ago, a time when anatomically modern humans had not yet evolved,” said Michael Hammer, an associate professor in the University of Arizona’s Department of Ecology and Evolutionary Biology.

Elhaik published a paper in the January 2014 issue of the European Journal of Human Genetics on his work; he used the opportunity to take a swipe at Hammer’s paper, published in the American Journal of Human Genetics.

“We have shown that the University of Arizona study lacks any scientific merit,” Elhaik claimed. “In fact, their hypothesis creates a sort of ‘space-time paradox’ whereby the most ancient individual belonging to the Homo sapiens species has not yet been born.”

Think of the Michael J. Fox film, Back to the Future. Marty was worried that his parents would not meet and so he would not be born in the future. “It’s the same idea,” Elhaik said.

Hammer told FoxNews.com he stands by his work.

“The paper by Elhaik and colleagues … does not present a convincing argument against our paper and unfortunately at times appears to display a lack of technical understanding of the subject area. We are in the process of submitting a rebuttal,” he said.

Identifying the very first Y chromosome of a genetic “Adam” would not mean scientists had located the Biblical figure Adam, explained Werner Arber, the Vatican’s top scientist, told FoxNews.com.

“Scientific investigations have no means to identify Adam and Eve and to sequence their genomes,” said Arber, current president of The Pontifical Academy of Sciences (PAS), the world’s first exclusively scientific academy, and a Nobel prize winner for his work in physiology. “Therefore, identification of Adam and Eve remains a matter of religious belief.”

Arber and other members of the PAS do closely monitor the field of phylogenetics, which is one of the hottest topics for genetic researchers. Scientists call the most recent common ancestor MCRA or A00 — it’s misleading to call the bearer of that chromosome Adam, noted Joe Pickrell from the New York Genome Center.

“At some point, a population geneticist had the clever idea of calling this common ancestor ‘Adam,’” he wrote on the Pickrell Labs website. “This is a biblical allusion, of course, and it probably was good for a bit of amusement a couple of decades ago. But it’s time to retire this metaphor–not only because it confuses the public … but because it confuses even practicing human population geneticists.”

Indeed, while metaphors are useful in communicating science, modern terminology shouldn’t be conflated with the Bible, explained Marcelo Sánchez Sorondo, chancellor of the PAS.

“Contemporary scientific language is not the language of the Bible,” Sorondo told FoxNews.com in an email. “Therefore, although the Bible adopted an early scientific language, it cannot be read in the light of today’s scientific language…This was clarified during the scientific revolution of Galileo (the founder of our Academy) when Cardinal Cesare Baronio rightly pointed out that the Bible tells us how to reach Heaven but not what Heaven is.”

“Of course this is also true for phylogenetics.”

But in a 2012 address to the Synod of Bishops, Arber said that the Bible story of Adam and Eve details existing scientific knowledge from the time, proposing “a logical sequence of events in which the creation of our planet Earth may have been followed by the establishment of the conditions for life.”

“It is our duty today to preserve (and where necessary restore) this consistency on the basis of the improved scientific knowledge now available. I am convinced that scientific knowledge and faith are complementary elements in our orientational knowledge and should remain so.”

Jeremy A. Kaplan is Science and Technology editor at FoxNews.com, where he heads up coverage of gadgets, the online world, space travel, nature, the environment, and more. Prior to joining Fox, he was executive editor of PC Magazine, co-host of the Fastest Geek competition, and a founding editor of GoodCleanTech.