The Bible provides two creation stories. In the first version, as told in chapter 1 of Genesis, the universe is created in six days, and on the sixth day, the first humans, consisting of an unspecified number of both men and women, are created. The second version from chapter 2 provides another creation story with a rather different sequence of events. God creates the first man, Adam, placed him in a garden of Eden, then creates all the animals ('beasts' and 'fowl'), and then only after Adam's loneliness is not satisfied by the animals, does God created Eve, the first woman. This may sound different from what you were taught in Sunday school, but if you don't believe it, read it for yourself. It's all there.
Modern science provides a similar story, except that the sequence of a couple steps are reversed and more time lapsed between the steps. Eve roamed the earth around 200,000 years ago, as determined by Rebecca Cann and other colleagues at the University of California-Berkeley. In 2000, another group of biologist from Stanford University led by Peter Underhill determined that Adam, the one man from whom all men alive today are descendant from, roamed the earth about 60,000 years ago. So Eve comes first, lives and dies, and 80,000 years later, Adam appears. Peter Underhill and his associated studied genetic variations of the Y chromosome. Like mitochondrial DNA, the Y chromosome is passed on from one generation to another with mutations occurring at a measurable rate. Unlike mitochondrial DNA, only men have Y chromosomes.
The original research article published in the November 2000 issue of Nature Genetics, or for a more readable version, see this BBC News article.
The First Australians
Finding 'mitochondrial Even' and 'Y-chromosomal Adam' was not the only fascinating finding from genetic 'fingerprinting'. We have a better understanding of pre-historic human migrational patterns. Spencer Wells, one the researchers involved in the 2000 Y-chromosome study wrote the Journal of Man. In the book, Dr. Wells traces the patterns of human migration from the first emigrants out of Africa 150,000 years ago to historic times. One of the most interesting migration pattern was the first group of homo sapiens to venture far away from the birthplace of humanity.
The first humans lived in southern and eastern Africa, a land today occupied by a chain of lakes (the Great Lakes of east Africa). Many of them may have lived along the Indian Ocean coastline and may have developed a beach combing lifestyle, eating seafood and maybe even learning to build small boats. Soon after, some time around 60,000 to 80,000 years ago, a small group of 1000 to 2000 people left Africa. They were among the beach combers. They crossed the Red Sea, hugging the coast, and went in easterly direction and kept walking until there was no more land. On their way through India, some of them decided to stay and they may have developed the earliest forms of Hinduism. (Later waves of humans arrived in India and intermingled with the original inhabits who taught them their religion). The rest of the nomads left a living trail of defiant and resilient peoples throughout south Asia: Malaysian Semangs, Andamanese of the Indian island chains of the coast of Thailand, and the Philippine Negritos. Some of them even made their way onto Australia and are the decedents of the Australian Aboriginal.
Genetic Genealogy
Another geneticist, Bryan Sykes wrote the popular book called Seven Daughters of Eve, that traces several descendants of mitochondrial Eve. By gathering the genetic information of hundreds of individuals from all over the world, we now have databases of genetic 'ethnic' groups. By comparing the genetic sequence of your own mitochondria, you can find out where your mother's mother's mother's mother's mother comes from (your material ancestry essentially). Men can also have their Y-chromosomal DNA analyzed to trace their paternal ancestry (any woman can find a male sibling or father to test).
Dr. Sykes' business Oxford Ancestry Ltd owns one of these databases and the tools to look at individuals' DNA sequences . For a fee of about $300, anyone can have their mitochondrial DNA analyzed to find out where their material ancestors came from, tracing them back much further then most people can trace their ancestry through conventional means. Yes there is some controversy regarding the conflict of interest, and some people question the ability to make certain claims, like finding specific villages of your ancestors. There is a big limitation as well. You can really only know two out of hundreds of your ancestors, as demonstrated in the chart below.
Dr. Sykes' company is not the only genetic ancestry business. There is a booming market among African Americans, mostly because details of their ancestry is lost. African Ancestry is one such company. Harvard professor Henry Louis Gates, Jr. recently stared in a PBS documentary featuring this method for uncovering ancestry among several celebrities.
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