How DNA Technology found Eve

God created humankind in his image,
in the image of God created them,
male and female he created them.
God blessed them,
and God said to them "Be fruitful and multiply...
                                   -Genesis 1:27-28 (NRSV)

Before people learned to write, we told stories.  Stories, myths and legends were often over dramatizations of real events that happened in the past.  Stories were how we know what knew.  They may not have been absolute truth, but they were never meant to be.  Non-literate people often have a better since of their intellectual limitations than literate people do.  Dramatizing the event often made it more entertaining or easier to remember.  The first people (or group of people) who learned to make fire became a sympathetic god who took pity on humans shivering in the dark, so he brought down the gift of fire from heaven.  Myths, sagas, and other elements of religion bring meaning to people's lives; they uncover a deeper truth not easily revealed by naturalistic explanations.


It would not be a stroke of genius to realize that population grows with each generation.  Couples tend to have more than two offspring to replace themselves.  Even today, most people live in towns or cities that seem larger than they were when they grow up.  There must have been a time when only one men and one women (or at least a small group of people consisting of men and women) existed in the world, whether you believed we were placed here magically by some divine force or morphed from another animal. So naturally, one of the first stories in our collection of stories to explain the universe would be the one about the first couple (or first people).


Just about every society in everything part of the world has a story about these first people.  The vast majority of them tell a story of a divine force creating them.  The Bible provides two stories.  The one quoted above is the first one, from Genesis chapter 1.  Humans are created in both male and female form.  It is not altogether clear whether it's two people or more.


Modern science provides another story; one that developed in the past 20 or so years.  A mutation occurred in another human-like animal somewhere in East Africa at roughly 250,000 years ago, some unusual environmental forces selected that mutation, and from a small group of mutants, the first people (
homo sapiens, to be specific) were made.  This small group of mutants numbered no more than a few thousand, and one of those mutants was Eve, the first person from whom everyone alive today is descended from.

How do we know this? In each one of our cells in our body, we have even smaller cells called mitochondria. Mitochondria are like little semi-autonomous factories whose major function is to use a chemical called oxygen to rip apart food molecules, which releases energy. That energy, in turn, allow us to move our muscles, think, digest our food, and other things that keep us alive.  The mitochondria have there own DNA, apart from the central store of 23 pairs of chromosomes of DNA in the middle of most cells. Unlike the chromosomal DNA, which we get half from our father and half from our mother, we get all of our mitochondrial DNA from our mother.


In 1987, a group of scientific researchers led by biologist Rebecca L. Cann analyzed the mutations that develop in the mitochondrial DNA and concluded that every person alive today, both men and women, are descended from a single woman that roamed the fields of East Africa some 200,000 years ago among that small group of  people.  This does not mean that Eve was the only woman alive at that time, but her mitochondrial DNA was the only mtDNA that survived. For more detail of this story, go direct to the source.



One important implication of this finding is that we can now unequivocally dismiss any claim that one race or group of people is more evolved then any other, because every person alive today or alive within that last 200,000 years has the same genetic structure, and by deduction, the same brain structure that those first few thousand people had in the time of mitochondrial Eve 200,000 years ago.  If you could transport Eve to the present day, she would have the same chance of getting through college as everyone alive today has.

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