I read that the first human is believed to be a human female born in Africa a few hudred thousand years ago?

Question

SOrry, I don't remember how long, but it wasn't much higher than 100,000. How are people estimated to be descended from a single female, and what were her parents? Were they a different species or something weird that was almost human but not quite there, or was she born one species, underwent a mutation and became another while an adult?

Please no bizarre defensive "Evolution is my life and if a religious person asks a question he must be attacking the theory which I am oddly defensive of" answers. I'll return the favor if you have a question about Judaism that you always wanted to ask, but were too afraid to. And please people who have some reason to believe they know answer. Thanks.

Pragmatic... you violated the rule about breaking down into a weird emotional defence of something not being attacked. You must now scold yourself.

Answer 1

I'll use the word "hominid" because it is more general than "human" and also because the word "human" has become politicized and, thus, has lost any purely scientific meaning.

There are several theories about the evolution of hominids, including differences of opinion regarding where they made their most recent advancements in brain size and mental powers.

One of those theories is called the Recent Out-Of-Africa theory, which is based on the DNA in mitochondria (which is inherited in humans only from the mother's side). The mtDNA in all modern humans traces back to an ancestress who lived about 135,000 years ago, and who is believed to have lived in Africa.

I can see how the timeframe was estimated, but I'm not sure about how the geographical location was determined. Also, there's a difference between locating a very distant ancestor geographically and determining the race of that ancestor. It's possible that even 135,000 years ago that non-Blacks lived in Africa. MtDNA Eve was not necessarily a Black hominid female.

The idea is that the "Mitochondrial Eve" for the entire population of extant hominids could not be so recent as 135,000 years unless there was a population bottleneck, or a sharp reduction in the number of hominids in the world, at about that time. Hence, say the ROOA theorists, tracing Mitochondrial Eve to Africa 135,000 years ago sets an early-bound to the time when modern humans emerged from Africa.

Anyway, I have a problem with the Recent Out-Of-Africa theory. For one thing, the mtDNA argument can be paralleled by another argument based on evidence from Y-chromosome DNA, which comes from the purely patriarchal line of male ancestors. The "Y-Chromosome Adam" of all modern humans has also been traced to Africa -- though again I'm not clear on how the location was identified -- but the time frame is only 75,000 years ago.

Mitochondrial Eve is twice as old as Y-Chromosome Adam! If a "population bottleneck" was necessary to make the lateness of Eve necessary, then how much more needful it is for the even more recent Adam. So, was there ANOTHER hominid population bottleneck? So, were all modern humans confined to Africa until only 75,000 years ago?

I doubt it very much! I think that the ROOA theorists have made more theory than their mtDNA argument can support. Perhaps two lines of ancestry for all extant hominids have been traced to Africa, but I doubt that this implies that there was any sort of bottleneck in the world hominid population, or that it implies that all of the ancestors of modern humans at the time were confined to Africa.

Just because you know that your mother's mother's mother's mother's mother's mother's mother came from France, and that your father's father's father's father's father's father's father came from France, does NOT mean that...

...your mother's father's mother's father's mother's father's mother came from France too! That ancestress might have been anywhere. And likewise for all other gender mixed lines of ancestry.

I think that hominids radiated out of Africa about a million years ago and that there has been considerable separate evolution, first in Homo erectus and then in Homo sapiens. Between Africans and Europeans, in particular, there are differences in brain size, intelligence, endocrine function, musculature, and deposition of body fat. Too much to be accounted for by only 135,000 years of divergence. Skin color differences are the least of many racial differences which exist.

Further, fossil and artifact evidence contradicts the Recent Out-Of-Africa theory and favors the theory that I believe is true, namely, the Ancient Candelabra theory.

Answer 2

Part of the problem is the notion of a "first human." There is no such individual.

Evolutionary theory holds that there was a long, unbroken chain of ancestry from the split between the hominids and the other primates about 6 million years ago. What we call "human" (or more technically, Homo sapiens) emerged somewhere between 100,000 to 200,000 years ago ... and the wide range is just a difficulty in defining exactly what is "human." But at no point was there some "non-human" female who gave birth to a "human" female.

Others are correct that you may be getting confused with the notion of "Mitochondrial Eve." This is just an individual (a female) for whom we can trace a maternal ancestry to all humans alive on the planet today. In other words, we know that:
1) Mitochondrial DNA (mtDNA) is inherited from our mother only (dad's mDNA is lost);
2) A child's mtDNA is thus identical to its mother's mtDNA, except for chance mutations (basically typos in the reproduction of that mtDNA);
3) We know the rate at which mutations enter into the mtDNA through transcription errors (those typos);
4) Thus we can look at the mtDNA between two or more individuals, and estimate how far back their most recent common maternal ancestor lived;
5) Based on samples of mtDNA from all populations, we can estimate that the most recent common maternal ancestor for all humans alive today (called "Mitochondrial Eve") lived about 150,000 years ago.

However, that most recent common maternal ancestor (Mitochondrial Eve) is NOT "the first human."

Incidentally, we can also do the same through the paternal line, by tracing back the Y-chromosomes of males (as this is always inherited from the father, not the mother). "Y-chromosome Adam" is estimated to have lived between 60,000 and 90,000 years ago.

Y-chromosome Adam was also NOT "the first human."

Answer 3

Such famous female skeleton was called "Lucy" by the Anthropologist.
It is believed the first anthropoids were chased out of the jungle by a competitor species or because of environmental changes, forcing them to adapt to survive in the savannas.

Already at the beginning of the 1900's it was experimentally observed in laboratory animals, that mutations DO occur.
Any mutation that gives a statistical advantage will be transmitted to the next generations. Which is the mechanism of the Evolution.
Nature favored the mutations (and Evolution) by means of the sexual reproduction and the reshuffling of genes during the fertilization process.
It is not clear to me why the Creationists think that the Evolution denies any God involvement.
God made the Laws and the Evolution is just a clever mechanism He has chosen for a dynamic Creation process which goes on even today towards perfection.
Who can deny Evolution now that it can be clearly traced by the analysis of the DNA?

Answer 4

You are talking about 'mitochondrial Eve'. The first thing to remember about this is that there were many individuals around at that time, not just Eve. Think of it this way:

Suppose that the population 200,000 years ago was a couple of hundred thousand. Say half of those were female. Well, some of them died before they gave birth, so in the next generation everyone was decended from around 95,000 females (rather than the initial 100,000). Some of those died before giving birth, so in the next generation, everyone was decended from, say 90,000 of the original females. It is fairly easy to see with examples that it doesn't take long before everyone around is decended from one of the original females.

All that was needed was a way to figure out when that one female lived. That is where the mitochondrial DNA comes in. It is only passed from a mother to her decendants; the father gives no contribution. When the comparisons between the DNA from populations today was compared, it was found that the mitochondrial Eve lived about 100-200,000 years ago.

It is interesting that a similar analysis can be made from the male lines of decent. In that way, it can be concluded that everyone is decended from some one male if you go back far enough. This 'Adam' almost certainly did not live at the same time as the Eve you are talking about. Again remember, this is a statistical thing, and many individuals lived with both the Adam and with the Eve.

Answer 5

What this comes from is that all human mitochondria share the same DNA. Mitochondrial DNA is passed through the female line, so suggesting there was a "first human".

However, things are never quite that simple. It's not as if Mr & Mrs Neanderthal suddenly gave rise to Claudia Schiffer. Species and boundaries are human impositions. This first woman may not have looked much different at all to her parents. .

Answer 6

You are merging "Mitochondrial Eve" and the appearance of Homo sapiens. Mitochondria are inherited from the mothers cells only. Mitochondria contain their own DNA (mtDNA). Analysis of mtDNA indicates that the female lineage (sons don't count in the line) traces back to a single female who lived in Africa about 150,000 years. She was not the only female of her time, but every other female line ended with no daughters (but possibly sons).

Homo sapiens emerged in Africa, about 130,000 years ago.