Evolution

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addams
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Re: Evolution

Postby addams » Sun Mar 22, 2015 8:19 pm UTC

That was an interesting link, Mokele.
https://en.wikipedia.org/wiki/Protocarnivorous_plant

It is so silly the things Reasonable People will argue about.
There is a strict definition of carnivorous for a plant that a human does not meet.
By this definition, many sun pitcher plants (Heliamphora)[6] and the cobra lily (Darlingtonia californica)[7] would not be included on a roster of carnivorous plants because they rely on symbiotic bacteria and other organisms to produce the necessary proteolytic enzymes.

Humans are at the mercy of their gut Flora, too.
Not the exact same way Darlingtonia is.

Darlingtonia is our Brother in a Green Suit.
No? Our Cousin?

We are all on the Family Tree of Life.
I'm sure of it. I've met Darlingtonia.
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Re: Evolution

Postby Mokele » Sun Mar 22, 2015 9:58 pm UTC

addams wrote:That was an interesting link, Mokele.
https://en.wikipedia.org/wiki/Protocarnivorous_plant

It is so silly the things Reasonable People will argue about.
There is a strict definition of carnivorous for a plant that a human does not meet.
By this definition, many sun pitcher plants (Heliamphora)[6] and the cobra lily (Darlingtonia californica)[7] would not be included on a roster of carnivorous plants because they rely on symbiotic bacteria and other organisms to produce the necessary proteolytic enzymes.

Humans are at the mercy of their gut Flora, too.
Not the exact same way Darlingtonia is.


Not exactly. While humans (and many other species) have symbiotic gut flora, we also produce our own digestive enzymes. A human digestive system without gut flora would still function, albeit not as effectively, but a Heliamphora or Darlingtonia would be incapable of any digestion at all.

It's like renting a house. In true carnivorous plants, as in animals, the landlord is the primary occupant (by biomass, not cell number) and pays most of the bills and you just rent one room and give them a small portion of the cash to help out. In protocarnivorous plants, the landlord is just some guy who owns the house, and you give them all the money they need to cover the mortgage payments, plus expenses and profit in return for a cozy home.
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Re: Evolution

Postby addams » Sun Mar 22, 2015 11:07 pm UTC

The House and Rent story was Hard for me. (ouch)
I don't want to argue the fine points; But....

I might learn that my concept of Human Digestion is Wrong.
I think: Without good working Symbiotic Relationships with the micro-organisms that live within,

We, the Human Animal, suffers malnutrition that can cross the line to starvation.
Even in the presence of sufficient food.

Gut Flora: The forgotten organ.
http://en.wikipedia.org/wiki/Gut_flora
The metabolic activities performed by these bacteria resemble those of an organ, leading some to liken gut bacteria to a "forgotten" organ.


Excuse me.
We may be stumbling off topic a bit.
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Re: Evolution

Postby Mokele » Mon Mar 23, 2015 2:30 pm UTC

addams wrote:The House and Rent story was Hard for me. (ouch)
I don't want to argue the fine points; But....

I might learn that my concept of Human Digestion is Wrong.
I think: Without good working Symbiotic Relationships with the micro-organisms that live within,

We, the Human Animal, suffers malnutrition that can cross the line to starvation.
Even in the presence of sufficient food.

Gut Flora: The forgotten organ.
http://en.wikipedia.org/wiki/Gut_flora
The metabolic activities performed by these bacteria resemble those of an organ, leading some to liken gut bacteria to a "forgotten" organ.


Excuse me.
We may be stumbling off topic a bit.


You're right, but it's the difference between a symbiosis that helps and does specific sub-tasks, and one that does absolutely all of the main task.

The question isn't "do the bacteria do anything?", the question is "does the plant do anything?" - yes in the case of Sarracenia, no in the case of Darlingtonia. Active digestion by the plant, even if bacterial symbosis is still needed, means the plant has adapted to carnivory in some manner beyond simply holding a pool of filthy water.
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Re: Evolution

Postby addams » Mon Mar 23, 2015 5:03 pm UTC

Holding a pool of filthy water?
Well....OK! You made my day.

That's funny stuff.
Poor little Darlingtonia.

And; Poor you and me.
Nothing but a Gut.

At least you and I can move away from our filth.
Poor little Darlingtonia must stand in filthy water, holding filthy water.

Gee. At least, Darlingtonia does not suffer the knowledge of how disgusting its life is.
Should I go tell them?

They tend to hang out in Crowds and Clusters.
I'll could tell the gregarious ones at the edge.
I'll could tell them to pass The Word.

Or; I could not bother.
They don't want to know.
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Some of us see The Gutter.
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Re: Evolution

Postby twinsen » Wed Mar 25, 2015 3:09 pm UTC

I think addams is right.

Taking off the bacteria, no matter that you secret enzymes, will not be ok at all.

Its like cutting of one of the hands of the animal. Yes, you will perform much better, with one hand , instead of cutting all your hands,
but Im not sure that it will make difference.

After all, survival is what matters, and if the nature requires from you to have 2 hands, you will die, and pure math 1 > 0 wont do the trick to save you.

So , can you call this bacteria "helping", just becouse its a part of a larger system. And not "doing all the work".
The same logic you can call the enzymes "helping".

Just my thoughts...

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Re: Evolution

Postby Izawwlgood » Wed Mar 25, 2015 3:20 pm UTC

I'm not sure what you're talking about... Are you suggesting we have two hands because one is redundant?
twinsen wrote:So , can you call this bacteria "helping", just becouse its a part of a larger system. And not "doing all the work".
The same logic you can call the enzymes "helping".
This is not true - enzymes are not independent 'entities', they are created by the organism that uses them.
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Re: Evolution

Postby Quercus » Wed Mar 25, 2015 3:36 pm UTC

There is a thread on whether the human gut microbiome is essential or not. The conclusion was that it's possible to survive without it, but you will need nutrient supplementation (e.g. for vitamin K) and you will have a severely screwed up immune system that will probably render you very vulnerable to infection. This concurs with my own knowledge on the subject.

That being said, I agree with Izawwlgood in not really getting twinsen's logic here.

Izawwlgood wrote:This is not true - enzymes are not independent 'entities', they are created by the organism that uses them.

Well, it's arguable to what degree gut bacteria are independent entities*. Sure, they're more independent than enzymes, but I don't know whether they could be considered truly independent - some of them are obligate symbionts, and there is increasing evidence that the immune system does an awful lot of "gardening" of what microbes it allows to grow, and which it doesn't, thus harnessing and shaping the gut microbiome.

*n.b. I'm not talking about bacteria in carnivorous plants here - it seems likely that those are indeed mostly or completely independent entities.

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Re: Evolution

Postby ucim » Thu Mar 26, 2015 1:31 am UTC

We can take this one level deeper - our cells themselves are not what they are cracked up to be. To wit: inside each of them are independent cells (called mitochondria) that while living there as autonomous beings, provide the motive power for our own cells to function. Their genetic material is passed on only through the female lineage and are a useful tool for genetic research.

But the point is that our own cells could not function without these "guests".

Put that in yer pipe and smoke it! :)

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Re: Evolution

Postby addams » Thu Mar 26, 2015 1:40 am UTC

Izawwlgood wrote:I'm not sure what you're talking about... Are you suggesting we have two hands because one is redundant?
twinsen wrote:So , can you call this bacteria "helping", just becouse its a part of a larger system. And not "doing all the work".
The same logic you can call the enzymes "helping".
This is not true - enzymes are not independent 'entities', they are created by the organism that uses them.

Yeah.
Enzymes are an entire series of wikipeddia articles.
The reason we have Two hands and not Four is loosely related to the kinds of enzymes we use.

Jeeze...That's a very loose knot.
Enzymes...What do we know about Those interesting Guys?

Yeah!
These guys!
http://en.wikipedia.org/wiki/Enzyme
I was uninterested in enzymes.
They seemed Redundant.

I mentioned my Underwhelmedness to a person that understood Enzymes and Loved the idea of Enzymes.

"Do you know how Long that would take? Without Enzymes?"
There was a lot of arm waving and excitement about Life!

"Life, as we know it, can not happen without Enzymes."
It took me a minute.
Pertrafied Wood forms about fast enough...Doesn't it?

....If ya' think about it.
The man had a point.

Cat Tail Reeds must have the Chemical Boost enzymes provide.
I like Cat Tail Reeds...Don't you?

Enzymes are Interesting Guys.
So are Surfactants!

How many hands do you want it to have?
Do you want it to lactate spiders silk and babysit?

It's Not a Stupid Question!
SpiderGoats BabySit.

https://www.youtube.com/watch?v=B0zT9CN3-50
https://www.youtube.com/watch?v=aWGmPqEujaI
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Re: Evolution

Postby twinsen » Thu Mar 26, 2015 7:50 am UTC

ucim wrote:We can take this one level deeper - our cells themselves are not what they are cracked up to be. To wit: inside each of them are independent cells (called mitochondria) that while living there as autonomous beings, provide the motive power for our own cells to function. Their genetic material is passed on only through the female lineage and are a useful tool for genetic research.

But the point is that our own cells could not function without these "guests".

Put that in yer pipe and smoke it! :)

Jose


If you recognize this tool, perhaps you accept, that our common ancestor was walking this earth ~ 150 000 years ago? In africa...
And not accepting the idea, that we evolved concurently in different points, from alot older ancestor ?

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Re: Evolution

Postby Izawwlgood » Thu Mar 26, 2015 12:13 pm UTC

ucim wrote:But the point is that our own cells could not function without these "guests".
Which is why chloroplasts and mitochondia are the strongest examples of endosymbionts we know of. Though, to be fair, there are chloroplast and mitochondrial modifying genes in virtually all life, so it's not like they're just chilling out doing their own thing, and we all look the other way as they help out.

twinsen wrote:If you recognize this tool, perhaps you accept, that our common ancestor was walking this earth ~ 150 000 years ago? In africa...
And not accepting the idea, that we evolved concurently in different points, from alot older ancestor ?
We did not evolve concurrently in different points. I'm pretty sure I've linked this to you, but you should read up on it. Yes. It's a wikipedia article - it's about the migratory pathway protohumans took out of Africa.

There were multiple homonids walking the planet at various times, but 'we' didn't 'evolve concurrently in different points'.
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Re: Evolution

Postby Quercus » Thu Mar 26, 2015 12:37 pm UTC

Izawwlgood wrote:
ucim wrote:But the point is that our own cells could not function without these "guests".
Which is why chloroplasts and mitochondia are the strongest examples of endosymbionts we know of. Though, to be fair, there are chloroplast and mitochondrial modifying genes in virtually all life, so it's not like they're just chilling out doing their own thing, and we all look the other way as they help out.


Indeed. Mitochondria have lost the vast majority of their genes to the nuclear genome of the host cell. They are as close to being "fully assimilated" as it's possible to get while still retaining clear evidence that they were once separate organisms. There are endosymbionts that are less thoroughly integrated though - some insect species are unable to reproduce if they are not infected by symbiotic Wolbachia bacteria. Wolbachia species are actually an interesting system to study to understand symbiotic relationships with microbes - some such infections are mutualistic, some are parasitic, some are a combination of both. Wolbachia are in some cases able to quite drastically alter the reproductive biology of their hosts, which is sometimes to the host's advantage, sometimes only to the advantage of the bacteria.

Interestingly there is a hypothesis (called Viral Eukaryogenesis) that the origin of the nucleus itself was a symbiotic DNA virus. I think that's pretty much unproven though, and perhaps a little bit of a "fringe" theory at this point.

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Re: Evolution

Postby addams » Thu Mar 26, 2015 1:27 pm UTC

This conversation is touching on Spencer Wells' 'Specialty'.
Part of the Grant was for making the data, if significant, available to Normal Folk.

It is an Old Movie.
I think, it is a Classic.

https://www.youtube.com/watch?v=nBJDGzzrMyQ
Spencer Wells introduced us to some of the Extended Family.
That Movie is like Gone With the Wind for Bio Majors.

The first time I watched Spencer Wells' tell the story of
The Journey of Man, I was so charmed,
If I had been a Bird, I would have fallen out of the Tree.

Spoiler:
An old american quip said,
"He could Charm the birds out of the Trees."

That's what I thought of Spencer Wells.
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We are all in The Gutter.
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Re: Evolution

Postby twinsen » Thu Mar 26, 2015 1:43 pm UTC

Izawwlgood wrote:
twinsen wrote:If you recognize this tool, perhaps you accept, that our common ancestor was walking this earth ~ 150 000 years ago? In africa...
And not accepting the idea, that we evolved concurently in different points, from alot older ancestor ?
We did not evolve concurrently in different points. I'm pretty sure I've linked this to you, but you should read up on it. Yes. It's a wikipedia article - it's about the migratory pathway protohumans took out of Africa.

There were multiple homonids walking the planet at various times, but 'we' didn't 'evolve concurrently in different points'.


Someone useless like you will link this: http://en.wikipedia.org/wiki/Recent_African_origin_of_modern_humans
Someone else will link http://en.wikipedia.org/wiki/Multiregional_origin_of_modern_humans.
Another one will link http://en.wikipedia.org/wiki/Bible

If you support the theory for african origin, please just say so. If you have arguments - please add them to the comment.
The following : "This happned, here look at this >>> wiki/Im-useless/and-wrong-too/random-stuff", is just really bad.


IF I WANT THAT CRAP, I HAVE WIKI TO READ.

Now on the subject. I think african origin is the quite possible explaination. Followed by this migration you talk about.
How long ago do you think our common ancestor walked this earth?

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Re: Evolution

Postby Izawwlgood » Thu Mar 26, 2015 2:11 pm UTC

twinsen wrote:Another one will link http://en.wikipedia.org/wiki/Bible
And that person has discredited themselves in a discussion about the anthropological origins of human beings, as well as a discussion about evolution.

If you are being that person, I think you've made your position abundantly-er clear.

twinsen wrote:Someone else will link http://en.wikipedia.org/wiki/Multiregio ... ern_humans.
You'll notice they all share a common ancestor. Can you, in your own words, describe what you think the multiregional hypothesis is suggesting? Or, perhaps, read the link, and pay attention to the very first sentence of the wiki - "The Multiregional hypothesis, Multiregional evolution (MRE) or Polycentric theory is a scientific model that provides an alternative explanation to the more widely accepted, "Out of Africa" model for the pattern of human evolution." Honestly, the only people I see really touting this model are racists looking for flimsy excuses to explain why Europeans are totes so much smarter than Africans.

twinsen wrote:If you support the theory for african origin, please just say so. If you have arguments - please add them to the comment.
The following : "This happned, here look at this >>> wiki/Im-useless/and-wrong-too/random-stuff", is just really bad.
I support the most widely accepted theory of African origin, which the multiregional origin hypothesis doesn't really refute, just contends that there are distinct clades arising within each regional sub population.

Now, the reason I (and others!) have linked wikis for you is because your ramblings convey that you have a very poor understanding of the science you are talking about. If you cannot be bothered to read the wikis that explain for you the things you are trying to opine on, I'm not sure why we should be bothered to converse with you.

twinsen wrote:Now on the subject. I think african origin is the quite possible explaination. Followed by this migration you talk about.
How long ago do you think our common ancestor walked this earth?
As it says in the wiki, about 200,000-60,000 years ago.

Since you keep skirting the issue and just throwing up your handwaves, why don't you clearly and concisely state what you think is going on?
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Re: Evolution

Postby ahammel » Thu Mar 26, 2015 2:16 pm UTC

Izawwlgood wrote:
twinsen wrote:Now on the subject. I think african origin is the quite possible explaination. Followed by this migration you talk about.
How long ago do you think our common ancestor walked this earth?
As it says in the wiki, about 200,000-60,000 years ago.

To clarify: that was Mitochondrial Eve (the most recent woman from whom all living women are matrilineally descended). The MRCA of all living humans lived much more recently.
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Re: Evolution

Postby Izawwlgood » Thu Mar 26, 2015 2:22 pm UTC

Eh, anatomically modern humans are dated around there. Oldest examples of out of Africa anatomically modern humans are 40-60,000 years ago.

Unless I'm mistaken about something.
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Re: Evolution

Postby ahammel » Thu Mar 26, 2015 2:28 pm UTC

Izawwlgood wrote:Eh, anatomically modern humans are dated around there. Oldest examples of out of Africa anatomically modern humans are 40-60,000 years ago.

Unless I'm mistaken about something.

The oldest anatomically modern humans and the most recent common ancestor of all living humans are very different things.
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Re: Evolution

Postby Izawwlgood » Thu Mar 26, 2015 2:30 pm UTC

Sorry, reading failure on my part. Yes. MRCA for humans today is much more recent.

EDIT: Uh, mixed results actually, I haven't really read up on this. Some reports say around 4,000 years ago, others say 99-200,000 years ago?
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Re: Evolution

Postby Whizbang » Thu Mar 26, 2015 2:35 pm UTC

http://en.wikipedia.org/wiki/Most_recen ... ing_humans

For the vast majority of humans, the MRCA happened sometime between 2,000 and 5,000 years ago (this number is justified by western explorers going around impregnating {read raping} indigenous populations around the world). There are some very isolated humans that would push that date much farther back for the MRCA for ALL humans.

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Re: Evolution

Postby Izawwlgood » Thu Mar 26, 2015 2:38 pm UTC

Can someone reconcile the MRCA estimate of 2-6,000 years ago, with the Mitochondrial Eve and Y-Chromosomal Adam estimates of ~100,000 years ago?
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Re: Evolution

Postby Sizik » Thu Mar 26, 2015 2:46 pm UTC

Wikipedia wrote: This estimate is based on a non-genetic, mathematical model that assumes random mating and does not take into account important aspects of human population substructure such as assortative mating and historical geographical constraints on interbreeding.
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Re: Evolution

Postby twinsen » Thu Mar 26, 2015 2:46 pm UTC

Izawwlgood, you black bro? :)

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Re: Evolution

Postby Whizbang » Thu Mar 26, 2015 2:46 pm UTC

The Mitochondrial Eve estimate can be reconciled by the fact that most western explorers were male, and so mitochondrial inheritance would still need to travel by normal migration patterns and time scales. Not sure about Y-Chromosomal Adam.

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Re: Evolution

Postby Izawwlgood » Thu Mar 26, 2015 2:53 pm UTC

So the computational modeling of MRCA seems pretty rough then. The genetic data seems to support the notion that Mitochondrial Eve was much further back.
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Re: Evolution

Postby ahammel » Thu Mar 26, 2015 2:58 pm UTC

Izawwlgood wrote:Can someone reconcile the MRCA estimate of 2-6,000 years ago, with the Mitochondrial Eve and Y-Chromosomal Adam estimates of ~100,000 years ago?

Matrilineal and patrilineal common ancestry is guaranteed to be further on the past than by simple descent. (The most recent common ancestor of me and my dad is my dad. The most recent common matrilineal common ancestor of me and my dad is hopefully nobody I know.) IIRC, the divergence is influenced by the inbreeding coefficient, but I don't remember the details.

Also worth noting that Mitochondrial Eve is a molecular clock estimate, while the MRCA date comes from a simulation.

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Re: Evolution

Postby Diadem » Thu Mar 26, 2015 3:08 pm UTC

Whizbang wrote:http://en.wikipedia.org/wiki/Most_recent_common_ancestor#TMRCA_of_all_living_humans

For the vast majority of humans, the MRCA happened sometime between 2,000 and 5,000 years ago (this number is justified by western explorers going around impregnating {read raping} indigenous populations around the world). There are some very isolated humans that would push that date much farther back for the MRCA for ALL humans.

Actually those MRCA (Most Common Recent Ancestor) estimates of 'between 2000 and 5000 years ago" already take into account isolated populations, though these estimates are based on mathematical modelling, and it can not be ruled out that some isolated populations managed to 'beat the odds', so to speak. Anyway the MRCA for the majority of humans is much more recent still, certainly after Christ, probably significantly so.

The difference between the MRCA and mitochondrial Eve is the type of allowed lineage. I am descended from mitochondrial Eve via an unbroken line of women. Mitochondrial Eve is the mother of the mother of the mother of <...> of the mother of my mother. And she is that for everybody living on earth. Likewise with Y-chromosomal Adam, but via the male line. However for the MRCA a mix is possible. So the MRCA could be an ancestor of my father's mother's father's father for me, but someone else could be descended from them via their mother's father's father's mother.

Now consider that I have 4 grandparents, but only one mother's mother. And I have 8 great-grandparents, but still only one mother's mother's mother.

So there are simply vastly more ways to be descended from the MRCA, and this is why they lived much more recent than either Mitochondrial Eve or Y-chromosomal Adam.

Whizbang wrote:The Mitochondrial Eve estimate can be reconciled by the fact that most western explorers were male, and so mitochondrial inheritance would still need to travel by normal migration patterns and time scales. Not sure about Y-Chromosomal Adam.

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Re: Evolution

Postby Whizbang » Thu Mar 26, 2015 3:18 pm UTC

Diadem wrote:
Whizbang wrote:The Mitochondrial Eve estimate can be reconciled by the fact that most western explorers were male, and so mitochondrial inheritance would still need to travel by normal migration patterns and time scales. Not sure about Y-Chromosomal Adam.

No. This has nothing to do with anything.


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Re: Evolution

Postby SecondTalon » Thu Mar 26, 2015 3:35 pm UTC

twinsen wrote:Izawwlgood, you black bro? :)

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Re: Evolution

Postby gmalivuk » Thu Mar 26, 2015 6:00 pm UTC

Whizbang wrote:The Mitochondrial Eve estimate can be reconciled by the fact that most western explorers were male, and so mitochondrial inheritance would still need to travel by normal migration patterns and time scales. Not sure about Y-Chromosomal Adam.
That could be part of an explanation of why matrilineal Eve and patrilineal Adam most likely lived at such different times. It has no connection with why they're both so different from the MRCA.

In any case, this existing thread is also about the common ancestor topic, and isn't tainted by racist/religious fuckery.
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Re: Evolution

Postby addams » Fri Mar 27, 2015 12:56 am UTC

Izawwlgood wrote:Can someone reconcile the MRCA estimate of 2-6,000 years ago, with the Mitochondrial Eve and Y-Chromosomal Adam estimates of ~100,000 years ago?

Yes.
Spencer Wells can.

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