countless songs and poems reference people with blue eyes whether they are seen as a mark of beauty a symbol of sadness despite their popularity in art blue eyes are relatively recent in human evolution as recent as the invention of writing itself a unique archaeological Discovery in 2006 researchers Unearthed the world's oldest confirmed blue-eyed individual dating back approximately 7,000 years this discovery helped to validate theories about the familial relationship among nearly all blue-eyed people this video will explore the genetic origins of blue eyes in humans the spread of the blueeyed Gene and the future of this genetic trait the basic explanation of eye color is often described as follows a person needs just one dominant browney gene from one parent to have brown eyes but must inherit two recessive blue-eyed genes one from each parent to have blue eyes however recent studies reveal that the genetics behind eye color are not so straightforward in reality two separate genes control eye color in humans Danish geneticist Hans iberg known for his discovery of the genetic mutation causing blue eyes States blue eye color are known to the public as a school example of in inheritance of monogenetic one gene inheritance however the variation in pigment concentration and the iris suggest the eye color genetics to be far more complex as supported by recent data in essence eye color is not determined by a single Gene passed from parent to offspring but by two genes working together a more complex chart would account for both of these genes these genes are known as oca2 and haak 2 in simplified terms the oca2 gene controls pigment in the stroma the tissue and blood vessels of the iris the colored part of the eye surrounding the puple while the hear 2 Gene is required to activate the oca2 gene to produce this pigment resulting in brown eyes if a person possesses a nonfunctioning oca2 gene they will all always have blue eyes because the hear 2 Gene cannot compensate for the defective oca2 Gene similarly if a person has a malfunctioning hierarchy 2 Gene the oca2 gene will underachieve failing to produce enough pigment to create brown eyes thereby resulting in blue eyes although these two genes are not directly related they influence each other in this dependent relationship both gen genes must function properly to produce brown eyes a genetic interaction known as epistasis due to this process it is actually possible though rare for two blue-eyed parents to have a brown-eyed child if one parent passes on a functional hiar 2 Gene and the other passes on a functional OCA 2 Gene rather than the defective versions the child could have brown eyes in addition to this more complex explanation of eye color inheritance a new study also suggests that all blue-eyed people descended from a single common ancestor Homo sapiens modern humans emerged around 200,000 years ago but the mutation responsible for blue eyes did not appear until roughly 10,000 years ago in a study led by Professor Hans iberg and a team from the University of Copenhagen researchers analyzed mitochondrial DNA from 155 blue-eyed individuals from Denmark two from Jordan five from turkey and 45 brown-eyed subjects they focused on the Locust specific location or position of a gene responsible for determining brown or blue eyes the findings revealed that more than 97% of blue-eyed individuals share the same H1 haer type A group of of genes inherited together from a single parent iberg and his team noted a shared haplotype among blue-eyed individuals is almost perfect and suggests the blue color phenotype is caused by a Founder mutation this indicates that the vast majority of people with blue eyes possess a single inherited genetic mutation rather than each having a unique mutation the study also included seven blue two-eyed Mediterranean individuals unrelated to the Danish participants as a control group and they too carried the H1 hapl type these individuals with the H1 hapet type all inherited the same genetic switch at the same location in their DNA whereas browney individuals exhibit a variety of melanin production and DNA variations with brown eyed phenotypes distributed among haplotypes H5 and h10 in 2006 researchers Unearthed a 7,000 yearold body from the Stone Age in the labran cave system in Leon Northern Spain genetic testing revealed that this individual had blue eyes while blue eyes themselves Are Not Unusual what is remarkable is that he is the earliest known person with this trait contrary to the expectation of a fair-haired fair skinned man his genetics present a unique mixture of characteristics although he is closely related to Modern Scandinavians he also possesses genes for dark skin along with curly dark hair and lactose intolerance this raises the question if blue-eyed people originated near the Black Sea and were primarily concentrated in northern Europe how did this individual end up in Spain to answer this question we need to explore Stone Age migratory patterns according to pical and Reich there are two theories of cultural migration demographic stasis versus demographic change in the demographic stasis Theory inhabitants of a particular region are the descendants of the first people to arrive there meaning that the people in a certain area were never integrated into or replaced by people from a subsequent migration conversely the demographic change theory deposits that the inhabitants of a region descended from people who arrived during periods of technological or cultural change thereby replacing the previous inhabitants these periods of change can be identified by sudden shifts in culture within the archaeological record essentially by tracking people through their technology such as tools and weapons and cultural artifacts such as pottery and jewelry we can trace how populations migrate ated from one place to another and carried their genetic traits with them specifically we can observe this during the Neolithic new stone age Revolution a period when humans began to cultivate crops domesticate animals and use polished stone tools prior to the Neolithic Revolution nearly all of humanity subsisted primarily by hunting and Gathering however after to the Neolithic Revolution small pockets of farming emerged initially in the Fertile Crescent and India and then spread across Eurasia the Neolithic Revolution occurred between 6,000 and 10,000 years ago and because people were better able to secure a steady food supply the population increased significantly the technologies that emerged during this time allow archaeologists and researchers to track cult cultural migrations from the Northwestern part of the Black Sea region where the first humans with blue eyes lived into the rest of Europe a study of Armenian haplotypes determined hospitable climatic conditions and the key Geographic position of the Armenian Highland suggest that it may have served as a conduit for several waves of expansion of the first agriculturalists from the near East to Europe and the north Caucasus this indicates that people migrated out of the Caucasus modern-day Georgia aeran and Armenia and into other parts of Europe henian write apparently the population migration of the first farmers from the Levant could have been both by land to Anatolia and the north Caucasus and by Maritime routes via Eastern Mediterranean Islands towards Continental Europe sparked by the population boom created by the Neolithic Revolution people began migrating faster and farther than ever before another study focusing specifically on the genetics of residents of the Iberian Peninsula excluding the bases reveals a blend of genetic traits from the Caucasus Central Asia and North Africa likely resulting from migration during the Neolithic era a study of eight Bronze Age individuals dated between 5,500 and 3 3,500 years ago shows an ad mixture between existing hunter gatherer groups and people from later migrations this indicates that people who migrated to this area began to integrate with the indigenous populations merging both their cultures and genetics how did the blueeyed gene persist if there's no overt evolutionary advantage to possessing it one argument is that those original groups of people with blue eyes produced Offspring with other blue-eyed individuals within their group resulting in a population where blue eyes became common however there are both objective and subjective benefits to having blue eyes subjectively blue eyes may make an individual more attractive to others objectively blue eyes filter light differently than dark eyes dark eyes like dark skin possess more pi M which protects these organs from sun damage making them particularly advantageous in the lowlight conditions of northern European Winters because people with light eyes are more sensitive to light they can see better in areas that lack sufficient sunlight for large portions of the year at the turn of the 20th century 50% of people living in the United States had blue eyes however as people increasingly marry outside their ethnic groups leading to more genetically diverse Offspring there has been a decline in blue eyes due to the dominance of brown-eyed genes currently only 177% of the US population one in six has blue eyes and only between 5 to 8% of people worldwide possess this trait green eyes are even rarer but they are a topic for another video despite being relatively new in human history blue eyes are already on the decline we used to convey Beauty as one writer notes no one knows what it's like to be the bad man to be the sad Man Behind Blue Eyes though the future of blue eyes is unclear nearly all living and dead blue-eyed individuals share a familial relationship through a single genetic mutation if you have blue eyes or know someone with blue eyes they are more than likely related to that 7,000 year old man whose Ms researchers found in a remote cave in Spain please like And 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