Mitochondrial Eve

an Eve. Now who is he? We should probably refresh everyone, especially those of you out there who can grow up attending Christian Sunday School or Jewish or just immersed in world myths. Eve, according to Christian and Hebraic and Islamic tradition, was the first woman, right, Adam was created by man out of dust, and then he's lonely. He evidently needs a friend, someone to do things for him, and so he ends up taking Adam's were about and turning it

into this woman Eve, which seems totally possible. Yeah, and then YadA, YadA, YadA, she borrows an apple from a snake and it's the downfall of man and then she has to suffer through painful childbirth and he has to get a job growing crops and it's just a big said sob story of the rest of the book, but the idea of this primordial mother figure. You see this throughout different systems of belief, in different myths and different religions. Eve herself her name comes from the Hebrew hallaw which

means life and life giving feminine power. And in the Salmutic tradition of Jewish literature, you have another figure, Lilith that shows up as the first wife of Adam, but she refused to listen to him and didn't want to obey him, and so she was transformed into a demon who then becomes this enemy of feminine reproduction and a destroyer of infants, so sort of an anti primordial mother figure. Then there are other characters such as Kiamet, the chaotic

primordial ocean goddess of ancient Babylon. There's Astra, the semantic mother goddess, and Greek mythology you have Pandora, the first woman, who also got into some similar curiosity related. Yeah, in Japanese mythology there's is an Armi no Mikoto, and then in Hinduism there's Sarupa, the first woman, the daughter of Brahma, and she's actually the female portion of Lord Brahma. She

is the counterpart to manage. Again, you see this idea throughout because on one level it's an embodiment of this idea of what female power is and the role females have in human society. And then on the other hand, we're fascinated by our origins. So we've always wondered where we came from, what we're our beginnings and was there, indeed a most distant ancestor we were to trace back our lineage far enough, would we come to a definite beginning, would we say, oh, well here here she is, here

he is. Well, you could never come back to the absolute beginning, right, But we can do something here today where we can blow ancestry dot Com away and is thirty something minutes right by talking about this idea of mitochondrial eve. Yes, this first woman. But we'll talk about more about what first woman means and in a little bit. But first, before we start talking about this mitochondrial eve from whom we all sprang this idea of this, let's

talk about evolution and something called the multi regional hypothesis. Yes, so multi regional hypothesis. This is the idea that human beings didn't necessarily originate with one particular explosion of evolution, but that this evolutionary explosion happened in several different places in the same way. You know, you hear about major inventions where oh, well, these guys invented the airplane at the same time as the right brothers. People were just

headed this way. The idea that, well, evolution was headed this way towards humans, and it just happened at several different points across the globe. It's far from the popular theory at this point. It's more the exception rather than

the rule. But prior to seven, this was the prevailing idea that our predecessor, Homo erectus had left Africa two million years ago and spread out around the entire world, and then these different populations adapted to their new environments by evolving into Homo sapiens, and although there was constant gene flow and interbreeding between these different populations, that everybody

remained part of the same species. So they thought this model was the best way to explain all of those Homeorectus fossils that they kept finding throughout Africa, Eurasia, and Australia. The most widely accepted model today though, is the recent African origin of modern humans model, or also known as the out of Africa model. It's also sometimes known as

the out of Africa to model. And this is why this holds that Homo sapiens evolved in Africa and between fifty six thousand and two hundred thousand years ago migrated into these other lands. The reason some people call it out of Africa two is that it involves a previous African exodus by tribes of Homo erectus. So following the scattering of the Homo sapiens, they eventually outlived the previous

Homo erectus excursion and become the dominent. And the explanations for the older fossils discovered elsewhere are basically representing hominid lineages that had since gone extinct a long time ago. So the idea with the recent African origin of modern humans model the out of Africa model, is that human evolution explodes once and that explosion consumes the globe, as

opposed to numerous explosions. Right. So, and the reason why we mentioned seven is because in January of seven, Rebecca can, Mark stone King, and Alan Wilson published a paper in nature that dropped a bombshell, this bombshell of the recent African origin model on our evolutionary doorsteps, so to speak.

The researchers examined the mitochondrial DNA taken from one forty seven people across all of today's major racial groups, and the researchers found that the lineage of all people alive today falls on one of two branches in humanities family tree. One of these branches consists of nothing but African lineage. The other continued into all other groups, including some African lineage.

So that was one revelation that they had, and I should also say to that the two distinct branches they discovered contained the mitochondrial DNA found in five populations Africa, Asia, European populations, Australian and New Guinea. And they found that in the branch that was not exclusively African, racial populations often had more than one lineage. For example, one New Guinea lineage finds its closest relative and a lineage present in Asia, not New Guinea. So this is all new

information to them. But here's the kicker. All of the lineages and both of the two branches can be traced back to mitochondrial eve, everyone can trace back his or her lineage back to a single common ancestor who lived around two hundred thousand years ago in East Africa. Yeah, it's pretty mind blowing. I mean, it's important to stress that we are not talking about even the actual like, oh, there was this single woman and she was made from a rib kind of a thing or anything of the sort.

There were women before mitochondria eve. There were other women at the same time. But just do the luck and the way things fell together, statistically, she ends up being the primordial mother figure for everyone that is alive today. Right, she was an ordinary woman for that time who became extraordinary because basically her genetic material is what actually survived. Right. And there's this idea that the reason why her genes subsisted while others died away is because of a theory

called evolutionary bottleneck. And this is a situation when a large majority of a member of species suddenly die out, bringing the species to the verge of extinction. So there could be a major catastrophic event, there could be an earthquake, some sort of special set of conditions that would whittle the population down. So it's possible that after a few generations that have experienced this catastrophic event, that the mitochondrial

DNA of other women died out. And we'll talk about this in a moment in a little bit more detail, But if a woman produces only male offspring, her minochondrial DNA will not be passed down. Since children don't receive mitochondrial DNA from their father. This means that while the women's sons will have her minochondrial DNA, her grandchildren won't in her line will be lost. But we know that

with mitochondrial eve this did not happen. Now, you mentioned bottlenecking there earlier, and this is something I found particularly interesting, just about the way populations change as humans expand out in ancient times. Two thousand seven, Cambridge researchers were looking at fifty three different human populations from around around the world, and specifically they're looking at skull shapes and genetic diversity, and they found that the farther the population was from Africa,

the less varied its genetic makeup. The reason being that its humans spread out from the cradle civilization, their population size is dropped, and as their population size is dropped, that means less genetic diversity to go around. In other words, if you were to migrate to this one area outside of Africa and there's not it's a long trip, we're going to die and there's a small group, you're going

to marry your cousin probably. And also nature is going to select the strong, the individuals that are suited for the new environments that are being encountered. Those are gonna be the ones that are going to survive. But if you were to have state in Africa, then you would have many more people to choose from to create more offspring with. So let's take a break and when we come back we will talk a little more about it.

So mitochondria DNA, what's the difference here? Okay, So DNA, located within the nucleus of each of your cells, determines your eye color, your racial features, susceptibility to certain diseases, and other defining characteristics. I think of it that way. Mitochondrial DNA, on the other hand, contains codes for making

proteins and carrying out other proces. Tessays mitochondria undertake. And this I wanted to talk about two because I think it's very interesting to see how DNA is replicated in the context of something like this when we're talking about two hundred thousand years ago. DNA is very long linear molecule. It's a coded version of how to make another copy

of you. Basically, it's your your blueprint. Right. It's composed of four subunits A, C, G, and T, and the sequence of those subunits that is basically the material that defines the blueprint. If you took all the DNA out of every cell in your body and you stretch it and to end, it would reach from here to the

moon and back thousands of times. Okay. So now think of copying the sequence and repeating it, and this incredibly long sequence you would see every once in a while a typo of sorts would occur, and that would account for the variation that we find with d N A okay. So another interesting note about DNA when you're thinking about mitochondrial DNA. In mitochondrial eve, that DNA is then changed

once again once it's combined with another set of DNA. Right, So when parents come together and they create offspring, they're merging their DNA. Mitochondrial DNA, on the other hand, is derived almost exclusively from your mother, and this is because the egg of a female human contains lots of Mt DNA mitochondrial DNA, while male sperm contains just a little

bit of mitochondria. And the reason for that is it because it helps it propel it basically, it gets it the energy, it propels it towards its race towards the egg for fertilization, and once it enters the egg, that mitochondria is destroyed after the sperm for Eliza's eggs, so any traces of that mitochondrial DNA from the sperm gone.

The only thing left is the female mitochondria in that egg. Okay, So that that's why mt DNA could be passed on only from mother to my Well, it can be passed onto the sun, but the sign can never pass it on, right, So that's why it's so tenacious, is because only the mother side of this actually survives and passes on. Right.

It's matrilineal, and it's easy to track, right, and it's not as variable as d n A because it doesn't have to go through these recombinations, right, It's just sort of like this pure packet that gets passed down at least on the female line. So that's why we have

this mitochondrial Eve. That's why these researchers said, Okay, we've been looking at d NA, let's look at mitochondria and see what sort of story it can tell us about our own origins and why they can then track our own lineage to this woman, to to mitochondrial eve who provided the blueprint for us. And again, I just want to go back and say that she was not the only woman on earth living at this time there, As

you said, there were women before her after. She probably didn't chat with snakes and eat strange fright, no more than the rest of us to right right, But she just gave us the little packet of life that all of us haven't common, which comes to this whole point that we've talked about before, that we are all related and much more so than we have ever thought. Yeah, and I think that's ultimately the beautiful thing about it.

I mean, we love the idea of there being an Eve, or there being any of these primordial original women Pandora or Satarupa, because it's the idea that is something that we have in common with everyone. And that's what this ultimately drives home, the story of human migration that at least ancestrally speaking, we are all Africans, and ancestrally speaking,

a large portion of us are ancestrally Indian. These are roots traced back through these migrations and really unitis as as a species well, and it really sort of makes the term race obsolete. And also, I want to read this bit to you from an Ionine article. It's called how mitochondrial Eve connected all humanity and rewrote human evolution. They say, okay, this is a game of numbers, but

really interesting. So let's say that you were born in and both of your parents were born in nineteen fifty, and your four grandparents were born in nineteen twenty five, your eight great grandparents in nineteen hundred, and so on and so on and so on. In other words, your number of ancestors doubles every twenty five years. Further back in time you go. So if you take this back just one thousand years, simple math demands that you have

well over because this is crazy. Five hundred billion ancestors in a single generation, considering that there's fewer than seven billion people on this planet, and even that is far far more than any other point in human history. There's something seriously wrong here. Okay, So this is where this

really gets interesting. In this article, they say, the solution, of course, is that you don't have five hundred billion distinct ancestors, but rather a much much smaller number of ancestors reappear over and over again in your family tree. So these are not doublegangers or anything. So instead of lots of different proto humans evolving separately over millions of years, the story of humanity is much shorter and much more

elegant and more interconnected than scientists had ever imagined. And this is a quote from Joseph T. Chang, Douglas lt Road, and Steve Olsen from their two thousand and four paper on something called m R c A. They say, no matter the languages we speak or the color of our skin, we share ancestors who planted rice on the banks of the Yanksoo, who first domesticated horses on the steps of the Ukraine, who hunted giant sloths in the forest of North and South America, and who labored to build the

great Pyramids of Cufu. And within two thousand years it is likely that everyone on Earth will be descended from most of us. It really widens what you can be proud of you know, you can be like the Pyramids, that was me. Yeah, it was me, giant sauce arrow, Arrow,

I had great ero skills. I have great Erroo skills, probably encoded in my d n A. Seriously, it is beautiful and I think it's something that we would all do well to keep in mind as we get through our daily lives and everything from observing how the next he is behaving on the train to what's going on

the news around the world. You know. Yeah, we've talked about this for this idea that we're all breathing these same molecules that have existed for millions and millions of years, and we're breathing each other's foot odor and that should connected some level and make us feel closer to one another.

But really, this is this is extraordinary to know that we are this much smaller pool that we all came from that we originally thought of in terms of these ancestors that appear over and over again, these patterns of our lineage. There we go, Well, let's call the robot over and let's do it. Just a quick listener mail here, all right. We heard from a listener by the name of Mike Mike right sentences, Hi, Robert and Jewling. Got

into your podcast last year and haven't stopped since. Great stuff to accompany a run on the treadmill, a long drive to work, or a road trip. Thanks for keeping my brain occupied. I listened to your Contact Lenses of the God's episode today and it reminded me very much of a great anime called Dinno Coil, in which a fictional Japanese city in the not too distant future has

been having fun introducing augmented reality into the world. The story revolves around the happening so have a bunch of kids with a R glasses augmented reality glasses and the adventures they get into, especially since a lot of the things they can do in the a R portion of the world is considered illegal. For example, they are frequently hunted by an oversized anti BUYERUS software that formats illegal

cyber information. In several episodes, students are seen typing on entirely virtual keyboards, composing emails and messages, as well as sending each other pop ups to bother them in class. The strange thing, as you might imagine, is that only people with a AIR glasses can see any of these things. In the off chance that you're into Japanese animation, you

should check the show out. So there you go. The Shain It is called Dinno Coil, and we also heard from a listener by the name of Austin about it as well, so it is apparently a fairly popular and I don't know if I mentioned it in the article or not. Some other science fiction properties that involve augmented reality or an augmented reality contact lenses. William Gibson has

in a few different books that involved virtual light. Specifically, Spook Country has a lot of with the concept, and Fire upon the Beat by Vernon Vinge, which I've not read. It's on my two read lists. Supposedly, highly advanced contact lenses play a crucial role in that as well. Hey, what do you think about Let us know if you find this information as you know, Lightning and hopeful as

the rest of us do. Let us know. You can find us on Facebook where our handle is stuff to Blow your Mind, and you can find us on Twitter where our handle is blow the Mind. And you can always drop us online at blow the Mind at Discovery dot com for more on this and thousands of other topics, does it, How stuff works, dot com