We may be underestimating the effect our lifestyle has on our evolutional traits. International research involving the University of Adelaide now demonstrated that beginning of farming changed human DNA. In fact, entire package – adaptation to changing diets, environments, disease-causing organisms and social organisation had effect on human DNA.
Agriculture was introduced in Europe about 8500 years ago. Of course, it immediately changes the way people live, but also left traces in human DNA. Scientists say that some evidence of this adaption can be detected in the patterns of genetic variation in today’s populations. However, they also note that modern genomes of humans only echo the past and cannot directly be connected to specific events. Scientists did manage to trace natural selection in real time studying the human DNA.
Professor Alan Cooper, one of the authors of the study, explained: “We’ve been able to take advantage of improved DNA extraction techniques and the largest collection of genome-wide datasets from ancient human remains. This has allowed us to identify specific genes that changed during and after transition from hunting and gathering to farming in Europe”. Scientists investigated DNA samples from the remains of 230 ancient individuals who lived between 3000 and 8500 years ago. These samples came from a variety of places from what now is Europe, Siberia and Turkey.
These samples are very limited, but scientists managed to trace down 12 positions on the genome where natural selection appears to have happened. Effect agriculture had on our genome is rather interesting. The changes of the genome include fatty acid metabolism, vitamin D levels, light skin pigmentation and light eye colour – all of them can be associated to decreasing exposure to sunlight in northern latitudes.
Scientists also found changes in DNA traits associated to immune system, which can be related to humans living in closer communities. Living in higher density communities affected viruses, therefore, human immune system had to adapt itself too. This study also allowed scientists to see height of humans growing over time.
Researches like this demonstrate how lifestyle of humans affects our DNA traits that are passes through generations. We can only imagine people in the future investigating how our current lifestyle affected our DNA.