Jun 23, 2011 13:49 GMT  ·  By
Population growth is one of the main engines driving evolution at a faster pace than ever before
   Population growth is one of the main engines driving evolution at a faster pace than ever before

According to the conclusions of a new scientific study, it would appear that evolution in modern humans has entered into full gear. Over the past 40,000 years or so, experts show, the rate at which our species evolves has accelerated remarkably.

The new results are in direct contradiction with the conclusions of other scientific studies, which have proposed that our species has stopped evolving, or that evolution takes place at a very slow pace.

It would appear that exponential population growth and cultural shifts are the primary reasons why we evolve so fast at this point. These data were derived from an examination of data collected by an international genomics project.

The research team, which is based at the University of Wisconsin Madison (UWM), suggests that the pace of evolution has quickened even more in the last 5,000 years, while humanity was still in the Stone Age.

The rate of positive selection has increased 100 times from any other period of human evolution. “We are more different genetically from people living 5,000 years ago than they were different from Neanderthals,” explains UWM anthropologist John Hawks.

The expert, who was the leader of the new research, says that the new study was made possible by impressive advancements made in the science of sequencing and deciphering the basic building code of life, DNA. Genes that allow us to become more fit for survival can now be identified.

Most of the changes human beings now displays appeared in order to allow the body to improve its resistance to microorganisms, or to allow for it to process new foods, that only became available with the advent of agriculture.

“In evolutionary terms, cultures that grow slowly are at a disadvantage, but the massive growth of human populations has led to far more genetic mutations,” Hawks says of the basic of the phenomenon.

“And every mutation that is advantageous to people has a chance of being selected and driven toward fixation. What we are catching is an exceptional time,” he adds, saying that his team mostly looked for single nucleotide polymorphisms (SNP) in the new study.

“Five thousand years is such a small sliver of time -- it's 100 to 200 generations ago. That's how long it's been since some of these genes originated, and today they are in 30 or 40 percent of people because they've had such an advantage. It's like 'invasion of the body snatchers,” Hawks comments.

The work he and his team conducted appears in a paper that was published in the journal Proceedings of the National Academy of Sciences (PNAS), Daily Galaxy reports.