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Last Eukaryotic Common Ancestor facilitates multi-cell complexity?

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Over at Design Matrix, in “First questions about LECA” (July 22, 2011), Mike Gene offers,

We have seen that science has discovered the last eukaryotic common ancestor was essentially as complex as a modern day eukaryotic cell (see here and here and here).

Okay, so in that respect, evolution did not happen. Can we get past that fact, or are we still stuck with funding propaganda from the Darwin lobby?

Furthermore, I have argued that this complex cell plan that has defined eukarya since the time of LECA has worked to facilitate the eventual emergence of metaozoan-type complexity.

So it was a design matrix? Evolution with a purpose?

Question: Why isn’t this guy testifying at the Texas school board hearings?

Comments
If there's only one lawyer in the courtroom, does it matter whether she is the first lawyer to leave or the last lawyer to leave? This seems like one of those Zeno paradoxes. If we go back to the time of the LUCA, was there a LUCA of all organisms alive at that time? And if we go back to that LUCA, was there an LUCA of all the organisms alive at that time? How many times do we need to repeat that to get to the FUCA? Would the FUCA be the LUCA?Mung
July 31, 2011
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Just to be fair, prosecutors can be just as slick and slippery.Ilion
July 31, 2011
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I have come to the conclusion that you display all the qualities of high paid slick and slippery defense attorney. So argue away.junkdnaforlife
July 31, 2011
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Fixed link: a href=https://uncommondescent.com/genetics/bryan-college-prof-defends-98-chimp-human-dna-identity/comment-page-1/#comment-393161Elizabeth Liddle
July 31, 2011
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junkdnaforlife, <a href=https://uncommondescent.com/genetics/bryan-college-prof-defends-98-chimp-human-dna-identity/comment-page-1/#comment-393161 here, suggests that post 1-9 of this thread suggest that I am "trolling". Let me address this point with reference to the cited posts: In post 1 I wrote?
Is it now clear to people that the Last, i.e the most recent, common ancestor of a group is not the same as the First common ancestor? That the LUCA is not the FUCA, and the LECA is not the FECA? Or that the FHCA is not the LHCA (Last Human Common ancestor). Not even if the FHCAs were Adam and Eve. Indeed, if the Flood were literally true, the LHCAs can have been no more remote than Mr and Mrs Noah, and possibly more recent. So while LECA might have been “essentially as complex as a modern day eukaryotic cell” that tells us nothing about how complex the FECA was.
Far from trolling, this post was on point, as the OP had written:
We have seen that science has discovered the last eukaryotic common ancestor was essentially as complex as a modern day eukaryotic cell (see here and here and here).
Okay, so in that respect, evolution did not happen.
Which seemed to me to imply that she thought that as the Last (i.e. most recent) Eukaryotic Common Ancestor) was "as complex as a modern day eukaryotic cell", it can have had no simpler precursors. I assumed that she made that inference because she assumed that the LECA was alsu the FECA (First Eukaryotic Common Ancestor). I'd seen something similar elsewhere, so I thought I would point out why the LECA need not be (indeed is extremely unlikely) to be the FECA, nor the FUCA the LUCA. Mung responded at #2:
The first most recent organism from which all organisms now living on Earth descend? How is that different from the last most recent organism from which all organisms now living on Earth descend?
Which is the question I had wanted to address, as (as Mung's question showed) at least some people seem unclear as to the answer. So I replied, @ #3:
OK, suppose Adam and Eve were the first humans, from whom all humans are descended. They have lots of kids, who interbreed, have more kids, and so on, until a global catastrophic Flood hits, with only eight survivors, all descendents of Adam and Eve. After the Flood, Shem, Ham and Japhet and their wives all have children. All those children are the grand children of Mr and Mrs Noah. Then the original ark survivors die, and the only inhabitants of earth are the grandchildren of Mr and Mrs Noah, and their descendents. At that point, the Last Human Ancestors of the entire world population are Mr and Mrs Noah. Adam and Eve are the FHCA, but Mr and Mrs Noah are the LHCA. For a while. After a bit longer, eventually someone even more recent will be the LHCA of all extant humans. The same applies to “mitochondrial Eve” (the last common human ancestor down the female line) and Y chromosome Adam (the last common human ancestor of human down the male line). Y chromosome Adam probably lived much later than mitochondrial Eve; furthermore, the identity of Mitochondrial Eve and Y Chromosomoe Adam changes, constantly – our mitochondrial Eve will be a different woman from our descendents’ Mitochondrial Eve. It’s also useful to note that unlike the biblical Adam and Eve and Noah and Mrs Noah, Y chromosome Adam and Mitochondrial Eve were not the only humans of their generation. The LHCA was not a single pair. Same with LECA and LUCA – they would have had lots of siblings, cousins, second cousins, third cousins (or, at least, there is no reason to postulated they didn’t). But most importantly they would have had parents and grandparents, and, indeed remote ancestors. One of these would have been the FECA and an even older one would have been the FUCA.
junkdnaforlife, @ #4,then posted:
Liz: Your fecas and fucas do not exist in any google search I run scholar or otherwise. If you have papers pertaining to fecas and fucas that would be great.
to which I replied, @ #6:
Well, junkdnaforlife, I just made up those acronyms! So if you google them, you will probably end up back here! But there’s plenty of literature on the concept of the Last…common ancestor” from which I drew. There’s one in wiki here, on Y chromosomal Adam and mitochondrial Eve: http://en.wikipedia.org/wiki/Mitochondrial_eve so you can work it out from that, I think. It’s just logic, but a bit counterintuitive at first. I once read a really good explanation, but I can’t find it online. ...
Meanwhile, nullasalus had posted, @ #5:
I find it bizarre that people are going off on the “LECA is not the FECA” thing, as if Mike doesn’t realize this. He clearly does, given what he’s writing. Do y’all think Mike’s argument here is that the LECA was created ex nihilo? If so, you’re dead wrong.
From which I inferred that nullasalus understands the issue exactly, and sees that any description of the LECA does not imply that it had no forebears was not "created ex nihilo", and so I finished my response to junkdnaforlife @ #6 with:
Nullasalus: I’m pleased to hear Mike realises that the LECA is not the FECA. Not everyone does, hence my post.
junkdnaforlife then replied (#7):
Liz: “There’s one in wiki here, on Y chromosomal Adam and mitochondrial Eve:” I was asking about feca and fuca. I am aware of mitoEve and yAdam. Recently, the terms feca and fuca have been bellowed repeatedly. Seeming to appear when a story about Leca is posted in a manner unflattering Darwinism. I was just wondering if it was a legitimate acronym or if it was introduced to muddy the water.
to which I responded @ #8:
Neither, junkdnaforlife, and if you read Nullasalus’s point you will see why. This is nothing to do with “unflattering Darwinism”, it’s just to do with clarifying the concept of the Last …common ancestor” which a lot of people (understandably) misunderstand. The Last Common Ancestor of a living population is not the same thing as its First Common Ancestor, unless, as Nullasalus says, you are positing that the Last Common Ancestor was created ex nihilo. And even then you could be wrong, as my Noah example should make clear.
In other words I reiterated what I should have said more clearly perhaps, in my first post, the simple point that: The Last Common Ancestor of a living population is not necessarily the same thing as its First Common Ancestor. It's can be a somewhat counterintuitive notion, but it is true! As the Noah story conveniently makes clear. junkdnaforlife then wrote, @ #9
A couple of articles were introduced on this site with reference to Leca in a manner unflattering to Darwinism. In response, Darwinists introduced to terms feca and fuca, in a manner that seemed to increase Darwin flattery. I searched for those terms. I found nothing. Nothing related to those acronyms in the context with how they were utilized on this site. Given the ideological lust that is known to consume Darwinists, and despite a rigorous search to find any paper referencing feca or fuca, I began to suspect that introducing the terms feca and fuca was done to muddy the water in a lawyer-like fashion. Now along with your admission… Well, junkdnaforlife, I just made up those acronyms! So if you google them, you will probably end up back here! I think that the introduction of feca and fuca being done to muddy the water is a reasonable inference. And btw, it was Dr.Rec not you who invented FECA. You can see the first injection of the term Feca here: https://uncommondescent.com.....work-here/
Which, I guess, is gives the reasoning behind junkdnaforlife's inference that I am "trolling". If Dr. Rec was the first to use the term, then I am more than happy to give him priority. I simply meant that it was not an acronym you'd likely find on google, because I just substituted F (for First) instead of L (for Last). I agree that it is extremely unlikely that I was the first person to do so, and indeed I've done it myself before - I recall using FUCA myself earlier on this blog. So I will happily concede that "I just made up those acronyms" was carelessly phrased. All I meant was that instead of typing "the first eukaryotic common ancestor", I typed FECA, assuming it would be understood by analogy with LECA, but not trying to suggest it was a well-known acronym that would get you many hits on google. So if that gave you "confirmation" that I was trying to "muddy the waters" it was unfounded confirmation. However, much more important is this: far from muddying the waters I was attempting to clarify them, by pointing out something that may be counterintuitive at first sight, but is actually obvious if you think, for example, of the paradigmatic population bottleneck story, namely the Ark. But I am really rather appalled that a section of this community has taken conversations like these and, having inferred, erroneously, that I am "trolling" or "dishonest", continue to cast aspersions on my integrity on the flimsiest of evidence! It's really trying, and although I am a patient woman, I am also an honest one, and find it very hard to retain my patience in the face of these seemingly endless implications, from a few regulars here, that I am not to be trusted. As I said to someone (Ilion I think) a few days ago; where trust is gone, there can be no communication. I am enjoying being here, and while I expected skepticism and distrust, I have been delighted, and heart-warmed by the degree of warmth with which I have been welcomed by many, despite the fact that my position on my issues is very different to the position held by most here. So I'll stay around, for as long as I am permitted, but I have also started a blog here: http://theskepticalzone.com/wp/ to which you are all welcome. It was started primarily to host the kind of extended conversations people have been kind enough to want to have with me here, but which are difficult to conduct on this site owing to the necessity of having to "squat" on convenient, if only tangentially relevant, threads in order to continue them as old threads are closed. My plan with the blog is to open authorship to a wide number of users, so if anyone would like to post an OP, whether addressed to me, or to a wider group, please let me know. And I'm more than happy to continue any conversations about FECAs and LECAs and FUCAs and LUCAs! I hope that has cleared some matters up. I dearly hope so. LizzieElizabeth Liddle
July 31, 2011
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Elizabeth, In a GA the organisms that will survive/reproduce are chosen based upon goals and parameters set by the designer of the GA. That is artificial selection, not natural selection. A solution to a problem may in fact exist, but does it follow that a GA will find that solution. My comment was not about unsolvable problems. My comment was about what it is that makes a problem solvable for a GA. GA's do not solve problems that they have not been designed to solve. Imagine the following scenario. I, as an intelligent design proponent, assert that I have designed and programmed a marvelous GA that can solve any solvable problem. You, as a design critic, are immediately convinced of the truth of ID and repent in sackcloth and ashes for ever doubting. Actually, you would do no such thing because you would be skeptical of my claim, and rightly so. Can you explain why? The solution has to exist with the "solution domain," to borrow from MG. At least he got that much right. The solution domain must be designed and programmed in to the GA. This is what leads to the existence of the solution within the search space.
In a GA the problem of survival is programmed. The solution is found by RM+NS.
That statement grossly misrepresents GA's and how they work. Please try to do better.
Mung, do you think it would help a critter to survive and breed if it had advance warning of predators, or advance notice of prey?
What does that have to do with anything? That an eye might benefit an organism is pretty irrelevant if no such thing as an eye exists within the search space. And if organisms exist without eyes then it ought to be plainly evident that eyes are not needed in order to survive and reproduce.Mung
July 25, 2011
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Mung:
But the solutions are found by rm+ns.
So you think that GA’s use natural selection? Really?
Yes. At least the ones I am familiar with do.
But the solutions are found by rm+ns.
The solutions are found. If the solution does not exist it cannot be found. This is true. Even GAs can't find solutions to insolvable problems.
The potential solution is programmed in to the GA or else the GA could never find it.
No, the potential solution is not programmed. What is programmed is RM+NS.
And Evolution solves them.
Who created eyes as a problem to be solved such that evolution could find eyes?
Mung, do you think it would help a critter to survive and breed if it had advance warning of predators, or advance notice of prey? If the answer is yes, then you have your answer. If the answer is no, I'm not sure how to help.
We both know that the problem has to be programmed in for an evolutionary search to be able to find it.
In a GA the problem of survival is programmed. The solution is found by RM+NS. In life, the problem of survival is presented by the environment. The solution is found by RM+NS.Elizabeth Liddle
July 25, 2011
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Dala: I'm glad you understand my reasoning, but why, in that case, is it not evidence for "rm+ns's creative power"? We start with a problem we don't know how to solve, and after large number of iterations of rm+ns we have a solution to the problem. How is that not creative?Elizabeth Liddle
July 25, 2011
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Elizabeth Liddle
In other words, in a GA, intelligent designers create the first population, and present the problems. Evolution solves them. In life, we don’t know how the first population came about, and the environment presents the problems. And Evolution solves them.
I understands your reasoning, but this is of course in no way evidence of rm+ns's creative power, whatsoever ...even if we let you start from a living cell. I understand that you BELIEVE in your argument and your conclusion, but all I see is a very far fetched hypotesis. Elizabeth, this is no evidence that rm+ns created "complex life" ...even if we had a living cell to start with. Anyways, when I asked for the one, best piece of specific evidence wich made you conclude that "the obvious" was not true, this is it? To me it seems very clear that you believe in your hypothesis because you have a very strong BELIEF that anything else is impossible, not because you have any proof that its right.Dala
July 25, 2011
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Elizabeth Liddle:
no, I don’t think that Darwinian evolution accounts for the Origin of Life, if by that, you mean the origin of the first entities capable of self-replication.
Why would Dala define life that way? That's an absurd definition of life. Only silly Darwinists define life that way and then only when they need to do so to "win" an argument.
What Darwinian mechanisms account for is adaptive design once those self-replication got started.
And this is false, and you know it is false, and yet you say it anyways, as if we should believe it to be true. We discussed this as recently as yesterday and you agreed that more than just self-replication was required. I thought you were going to do a better job of lawyer-proofing your posts.
But the solutions are found by rm+ns.
So you think that GA's use natural selection? Really?
But the solutions are found by rm+ns.
The solutions are found. If the solution does not exist it cannot be found. The potential solution is programmed in to the GA or else the GA could never find it.
And Evolution solves them.
Who created eyes as a problem to be solved such that evolution could find eyes? We both know that the problem has to be programmed in for an evolutionary search to be able to find it.Mung
July 25, 2011
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Yes, of course intelligence is involved in setting up the GA, because the NASA people have a specific problem they want to solve, and, in any case, they have to set up the whole thing, including the self-replicating virtual organisms. But the counterpart of the first thing is the environment itself - the environment sets problems for organisms to solve, while the second, is, as I said, a given (Darwinian processes do not account for how the self-replicators got their in the first place). But the solutions are found by rm+ns. In other words, in a GA, intelligent designers create the first population, and present the problems. Evolution solves them. In life, we don't know how the first population came about, and the environment presents the problems. And Evolution solves them.Elizabeth Liddle
July 25, 2011
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Elizabeth Liddle
And yes, do offer genetic algorithms as an example of how this works.
Ok. So, as in the mentined example where NASA uses an evolutionary algorithm to design a signalfilter, you honestly don't see how 'intelligence' is involved in the designprocess? At least I understand what you consider a proof. ...and I am a bit surprised.Dala
July 25, 2011
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Dala: no, I don't think that Darwinian evolution accounts for the Origin of Life, if by that, you mean the origin of the first entities capable of self-replication. What Darwinian mechanisms account for is adaptive design once those self-replication got started. So far, although there are ideas, there are no completely persuasive theories, and few that even make testable predictions AFAIK. But once those first self-replicators got going, my argument is that replication with modification plus natural selection (i.e. Darwinian evolution) acts as an intelligent, though non-intentional process, the result of which is organisms that are exquisitely "designed" for their environments. And yes, do offer genetic algorithms as an example of how this works. As a specific example, you might like to ask Dr Bot, as he works with genetic algorithms, but I have written crude ones myself. I'm hoping, though, to start writing a simulation in which I don't even start with self-replicators, but let them emerge, and "design themselves" to replicate better. Not sure I can do it though :)Elizabeth Liddle
July 25, 2011
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Isn’t the question centered on the insertion of non-randomness in the natural selection debate? If it turns out to be true, then everything found in nature looks like it is involved in some sort of design? If true – then why not teach it in our schools?Tim AJ
July 25, 2011
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Elizabeth, I have a question which I asked you in another thread but which I didn't really get an answer to, and I never got around to follow up the thread. In the other thread you agreed that it seemed obvious that life was designed intelligently, but you claimed that we know that no additional 'intelligence' is needed. According to you, todays science knows that life can be explained using the known fundamental forces in nature. I therefore asked you how this is known. I asked you for one SPECIFIC example. You answered me, but didnt give me a specific example. Instead you gave me a long list of vague ones. Usually its very difficult to get a straight answer to the question, but I have gotten the following three SPECFIC examples of 'proof' from other evolutionists. 1. One Darwinist felt NASA's use of "evolutionary algorithms" in the develoment of, for example, antennas and filters,(http://ti.arc.nasa.gov/tech/asr/aces/) was a proof that randomness can create life. Would you agree this is a proof? 2. Another Darwinist proved that the known physical forces created life by refering me to the "long term E-coli experiment", where variations in e-coli bacteira are observed. (http://myxo.css.msu.edu/ecoli/) Would you agree this is a proof? 3. The last exampleof a 'proof' I have been able to get was the "folding@home" computersimulation of protein-folding. (http://folding.stanford.edu/) Would you agree this is a proof? Do you agrre that these examples are proof of anything? If not, have you got a SPECIFIC example of your own? I also wanted to follow up a second point. Again, it seems obvious that intelligence is playing a part, even if we can't explain how. ONE idea, which you said you felt was a 'viable one', was the idea that intelligence might be a 'fundamental force' in nature. But then you wrote a few things after that which made me think maybe I missunderstood you. When I said a 'fundamental force' I mean a force which does not arise from any of the other four fundamental forces (strong/weak nuclear forces, electromagnetic force and gravity.) So, just to make sure I don't missunderstood, do you think it's a 'viable idea' that intelligence can not be explained in any of the known physical forces in nature?Dala
July 25, 2011
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It’s just logic...
Oh. So now you're being logical? Does that mean it's not scientific? It that it's only provisional? You could be wrong? I trust you're remaining humble.Mung
July 24, 2011
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I’m pleased to hear Mike realises that the LECA is not the FECA. Not everyone does, hence my post.
Well, junkdnaforlife, I just made up those acronyms! So if you google them, you will probably end up back here!
Mung
July 24, 2011
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Yes, Mike realizes that the 'LECA' is not the 'FECA'. No, he is not positing that the LECA was created ex nihilo. But re: "unflattering Darwinism", Mike advances the idea of a teleological evolution, in contrast to non-teleological. He clearly sees reason to believe that the data we have on the LECA fits better with his view of evolution than the "Darwinian" account. To accept evolution is not the same as accepting "Darwinism".nullasalus
July 24, 2011
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A couple of articles were introduced on this site with reference to Leca in a manner unflattering to Darwinism. In response, Darwinists introduced to terms feca and fuca, in a manner that seemed to increase Darwin flattery. I searched for those terms. I found nothing. Nothing related to those acronyms in the context with how they were utilized on this site. Given the ideological lust that is known to consume Darwinists, and despite a rigorous search to find any paper referencing feca or fuca, I began to suspect that introducing the terms feca and fuca was done to muddy the water in a lawyer-like fashion. Now along with your admission...
Well, junkdnaforlife, I just made up those acronyms! So if you google them, you will probably end up back here!
I think that the introduction of feca and fuca being done to muddy the water is a reasonable inference. And btw, it was Dr.Rec not you who invented FECA. You can see the first injection of the term Feca here: https://uncommondescent.com/darwinism/complexity-of-earliest-animalplant-cell-is-real-no-tautology-at-work-here/junkdnaforlife
July 24, 2011
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Neither, junkdnaforlife, and if you read Nullasalus's point you will see why. This is nothing to do with "unflattering Darwinism", it's just to do with clarifying the concept of the Last ...common ancestor" which a lot of people (understandably) misunderstand. The Last Common Ancestor of a living population is not the same thing as its First Common Ancestor, unless, as Nullasalus says, you are positing that the Last Common Ancestor was created ex nihilo. And even then you could be wrong, as my Noah example should make clear.Elizabeth Liddle
July 24, 2011
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Liz: "There’s one in wiki here, on Y chromosomal Adam and mitochondrial Eve:" I was asking about feca and fuca. I am aware of mitoEve and yAdam. Recently, the terms feca and fuca have been bellowed repeatedly. Seeming to appear when a story about Leca is posted in a manner unflattering Darwinism. I was just wondering if it was a legitimate acronym or if it was introduced to muddy the water.junkdnaforlife
July 24, 2011
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Well, junkdnaforlife, I just made up those acronyms! So if you google them, you will probably end up back here! But there's plenty of literature on the concept of the Last...common ancestor" from which I drew. There's one in wiki here, on Y chromosomal Adam and mitochondrial Eve: http://en.wikipedia.org/wiki/Mitochondrial_eve so you can work it out from that, I think. It's just logic, but a bit counterintuitive at first. I once read a really good explanation, but I can't find it online. Nullasalus: I'm pleased to hear Mike realises that the LECA is not the FECA. Not everyone does, hence my post.Elizabeth Liddle
July 24, 2011
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I find it bizarre that people are going off on the "LECA is not the FECA" thing, as if Mike doesn't realize this. He clearly does, given what he's writing. Do y'all think Mike's argument here is that the LECA was created ex nihilo? If so, you're dead wrong.nullasalus
July 24, 2011
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Liz: Your fecas and fucas do not exist in any google search I run scholar or otherwise. If you have papers pertaining to fecas and fucas that would be great.junkdnaforlife
July 24, 2011
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OK, suppose Adam and Eve were the first humans, from whom all humans are descended. They have lots of kids, who interbreed, have more kids, and so on, until a global catastrophic Flood hits, with only eight survivors, all descendents of Adam and Eve. After the Flood, Shem, Ham and Japhet and their wives all have children. All those children are the grand children of Mr and Mrs Noah. Then the original ark survivors die, and the only inhabitants of earth are the grandchildren of Mr and Mrs Noah, and their descendents. At that point, the Last Human Ancestors of the entire world population are Mr and Mrs Noah. Adam and Eve are the FHCA, but Mr and Mrs Noah are the LHCA. For a while. After a bit longer, eventually someone even more recent will be the LHCA of all extant humans. The same applies to "mitochondrial Eve" (the last common human ancestor down the female line) and Y chromosome Adam (the last common human ancestor of human down the male line). Y chromosome Adam probably lived much later than mitochondrial Eve; furthermore, the identity of Mitochondrial Eve and Y Chromosomoe Adam changes, constantly - our mitochondrial Eve will be a different woman from our descendents' Mitochondrial Eve. It's also useful to note that unlike the biblical Adam and Eve and Noah and Mrs Noah, Y chromosome Adam and Mitochondrial Eve were not the only humans of their generation. The LHCA was not a single pair. Same with LECA and LUCA - they would have had lots of siblings, cousins, second cousins, third cousins (or, at least, there is no reason to postulated they didn't). But most importantly they would have had parents and grandparents, and, indeed remote ancestors. One of these would have been the FECA and an even older one would have been the FUCA.Elizabeth Liddle
July 24, 2011
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The first most recent organism from which all organisms now living on Earth descend? How is that different from the last most recent organism from which all organisms now living on Earth descend?Mung
July 24, 2011
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Is it now clear to people that the Last, i.e the most recent, common ancestor of a group is not the same as the First common ancestor? That the LUCA is not the FUCA, and the LECA is not the FECA? Or that the FHCA is not the LHCA (Last Human Common ancestor). Not even if the FHCAs were Adam and Eve. Indeed, if the Flood were literally true, the LHCAs can have been no more remote than Mr and Mrs Noah, and possibly more recent. So while LECA might have been "essentially as complex as a modern day eukaryotic cell" that tells us nothing about how complex the FECA was.Elizabeth Liddle
July 24, 2011
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PDT

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