[JerRocks2day]

I've started watching a evolution documentary in CPB class and it claims that a young woman from Africa millions of years ago, is responsible for all of our genes.

According to wikipedia, this is a mitochondria eve. I feel skeptical about the idea.

But has anybody else watched the documentary? It's from Discovery channel.

[snizzle]

Originally Posted by JerRocks2day

I've started watching a evolution documentary in CPB class and it claims that a young woman from Africa millions of years ago, is responsible for all of our genes.

According to wikipedia, this is a mitochondria eve. I feel skeptical about the idea.

But has anybody else watched the documentary? It's from Discovery channel.

Although I love the Discovery Channel (but don't get to watch it much), you have to take most of it (especially regarding Christianity) with a grain of salt.
-shane

[S.B.Nichols]

It's Hera from BSG!

Actually, according to wikipedia

Originally Posted by wikipedia

Mitochondrial Eve is the MRCA of all humans via the mitochondrial DNA pathway, not the unqualified MRCA of all humanity. All living humans can trace their ancestry back to the MRCA via at least one of their parents, but Mitochondrial Eve is defined via the maternal line. Therefore, she necessarily lived at least as long, though likely much longer, ago than the MRCA of all humanity.

It doesn't completely make sense. If everyone can trace it back thru at least one of their parents, why can't they trace it back through both of their parents (assuming their parents are also lumped into the 'everyone' category, and everyone has a mother). But, that may just be bad wording on the part of the wiki author.

[Rainer.]

I haven't seen the documentary, but I am familiar with this concept.

One individual may have been responsible for all our mitochondrial genes. Mitochondrial genes only get passed from mother to child through the egg (sperm contain no mitochondria), and really only affect the function of the mitochondria. Every human's mitochondrial DNA can be sequenced and a % difference of the sequence of the mitochondrial DNA can be used to determine when a most recent common ancestor, MRCA, was around.

I believe a popular hypothesis is that there was a human population bottleneck around 70K years ago due to the Toba volcanic eruption that knocked down the population to few closely related individuals that went on to make the rest of the human population, and this hypothesis is based heavily on mitochondrial DNA dating the MRCA of most humans to this time.

I think the term Mitochondrial Eve is misleading, though, because searching for one MRCA is silly when speciation is really evolution which applies to a population, and not a single individual. All our mitochondrial DNA is similar enough to all have come from one woman 170K years ago, but looking for the root of a species through two individuals is not really how evolution works.

Disclaimer: I am not taking a stand for/against evolution, but presenting scientific information as it has been presented to me.

[ICTHUS]

Originally Posted by Rainer.

(sperm contain no mitochondria)

This is incorrect. All living cells contain mitochondria, as they are necessary for cellular respiration and the production of energy via the conversion of glucose into adenosine tri/diphosphate (ATP/ADP).

The reason that the father's mtDNA is not transferred to the offspring is that the mtDNA in sperm are not transferred to the zygote upon fertilization: they are only used to propel the sperm forward to where it needs to go. This should be evident upon examining where the mitochondria in sperm are located: below the head (where the chromosomes are stored) and in the midpiece. Since the only material from the sperm to go into the zygote upon fertilization is in the head, humans do not inherit mtDNA from their fathers, but only their mothers (since an oocyte's mtDNA remains within it after fertilzation)

[Rainer.]

Originally Posted by ICTHUS

This is incorrect. All living cells contain mitochondria, as they are necessary for cellular respiration and the production of energy via the conversion of glucose into adenosine tri/diphosphate (ATP/ADP).

The reason that the father's mtDNA is not transferred to the offspring is that the mtDNA in sperm are not transferred to the zygote upon fertilization: they are only used to propel the sperm forward to where it needs to go. This should be evident upon examining where the mitochondria in sperm are located: below the head (where the chromosomes are stored) and in the midpiece. Since the only material from the sperm to go into the zygote upon fertilization is in the head, humans do not inherit mtDNA from their fathers, but only their mothers (since an oocyte's mtDNA remains within it after fertilzation)

Technicality, but yes you are right. The sperm head contains no mitochondria, but the tail does.

[jthomas1600]

Originally Posted by snizzle

Although I love the Discovery Channel (but don't get to watch it much), you have to take most of it (especially regarding Christianity) with a grain of salt.
-shane

Ditto. This goes for all TV as far as I'm concerned. There seems to be a current trend for channels like the history channel to try and explain the parting of the red sea by extreme tides and wind etc.

[jesus_for_me]

Originally Posted by JerRocks2day

I've started watching a evolution documentary in CPB class and it claims that a young woman from Africa millions of years ago, is responsible for all of our genes.

the bolded is your 1st problem.if you are looking for science don't go to sci fi for answers.if you are looking for facts do not look at a hypothesis.

the 1st problem here is ignoring basic genetics. look at africa and the ppl who live there.almost 100% dominant traits.if this really were the case there would be no blond hair or blue eye's or anything like that. they exist in africa now due to interbreeding(thus pointing out that we did NOT come from an african woman.) but would not have if that was the place of human origin.second.we cannot have all come from a woman because she would have had no man to breed with. where is the hypothesis of the mitochondria adam?if you ask me this documentary is a peice of racist/sexist propaganda.the whole premis stinks of it.point number one:we all came from a black person(thus making them a more pure and supeirior ppl), and point number 2:we all came from one woman without the help of a man(thus making them the better part of the species of humanity)

According to wikipedia, this is a mitochondria eve. I feel skeptical about the idea.

and this is the second problem. I don't have anything against online ecyclopedias but when it can be edited on daily basis I find it very hard to trust as accurate.

this is all just my 2 cents worth tho so take it all with a grain of salt.

[thesteve]

Originally Posted by jesus_for_me

the bolded is your 1st problem.if you are looking for science don't go to sci fi for answers.if you are looking for facts do not look at a hypothesis.

the 1st problem here is ignoring basic genetics. look at africa and the ppl who live there.almost 100% dominant traits.if this really were the case there would be no blond hair or blue eye's or anything like that. they exist in africa now due to interbreeding(thus pointing out that we did NOT come from an african woman.) but would not have if that was the place of human origin.second.we cannot have all come from a woman because she would have had no man to breed with. where is the hypothesis of the mitochondria adam?if you ask me this documentary is a peice of racist/sexist propaganda.the whole premis stinks of it.point number one:we all came from a black person(thus making them a more pure and supeirior ppl), and point number 2:we all came from one woman without the help of a man(thus making them the better part of the species of humanity)

and this is the second problem. I don't have anything against online ecyclopedias but when it can be edited on daily basis I find it very hard to trust as accurate.

this is all just my 2 cents worth tho so take it all with a grain of salt.

Do you understand what the mitochondrial Eve is? Based on your response here, it seems like you're attacking a premise without really understanding what the premise means.

[Ax]

I find it very hard to believe that our Y Chromosomal Adam and our Mitochondrial Eve lived that far apart, unless "Eve" was a major prostitute. This seems like a silly concept to me.

[thesteve]

Originally Posted by Kitty-Doggie

I find it very hard to believe that our Y Chromosomal Adam and our Mitochondrial Eve lived that far apart, unless "Eve" was a major prostitute. This seems like a silly concept to me.

I'm not sure what you mean here, general consensus is that the two were separated by tens of thousands of years.

[Ax]

it's just that it would make sense that our MRCAs would have been mates. Unless mtdEve had very very many mates that were all direct male ascendants of Y-Adam.

[S.B.Nichols]

That's actually kinda what it means, except that m-Eve would have only had to have had one (or more) daughter, granddaughter, etc.... who would have gotten it on with a descendants of y-Adam

[thesteve]

Originally Posted by Kitty-Doggie

it's just that it would make sense that our MCRAs would have been mates. Unless mtdEve had very very many mates that were all direct male ascendants of Y-Adam.

That's not really how MCRAs work though. It's actually thought that over time, depending on birth rates, the Y-Adam shifts depending on what male birth lines die out.

[Ax]

Wouldn't that mean that mtdEve would be older than Y-Adam? I thought I read that Adam was older.. maybe i got confused.


*edit*

According to wiki Eve is Older than Adam so that makes more sense.