Talk:Identical ancestors point

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[edit] ancestors to IAP

Perhaps should note that as we move back from the IAP the number of individuals (within the species) gets smaller and smaller until eventually there is only one. This would be the Last common ancestor (see Wikipedia). Depending on whether Multiregional or Recent Replacement is correct, the date of the LCA of modern man is either 2 Million BCE or 40,000. The LCA does however, exist, and leads to the IAP. Tom Schmal 00:41, 2 November 2007 (UTC)

Your understanding of the LCA is incorrect. LCA is basically the same as MRCA, except that nowadays MRCA is used more often than not to define most recent common ancestor among a species (that is, common ancestor of a set of people), while LCA is used to define most recent common ancestor of a set of species. You can think of LCA as what Dawkins calls 'concestor'. Notice that both LCA and MRCA only make sense when applied to a 'set' of organisms. Pay attention to the words 'most recent' and 'common'. See Most_recent_common_ancestor#MRCA_of_different_species. Fred Hsu 02:24, 2 November 2007 (UTC)
What you are trying to describe is the original individual whose gene undergoes a mutation which eventually become universal in an entire population later. This individual has contemporaries. Think about it, how would a single individual mate? Fred Hsu 02:24, 2 November 2007 (UTC)

[edit] Page restored

Cool. I guess this will make it clear to people that identical ancestors point is NOT the same as MRCA. Fred Hsu 14:16, 23 July 2007 (UTC)

I think the Exact Identical ancestor points listed in this article are questionable. (by anonymous editor)

[edit] removed the caveat section

I removed this:

It should be noted that the 'identical ancestors point' is dependent upon the single recent origin hypothesis. Should humans have evolved from multiple sources and then merged, the concept cannot be correct. It should be noted that some species today (i.e. birds) have merged (also called species integration; thus it is possible for humans, as well, to have come from multiple origins. See the multiregional hypothesis for the alternate view.

Please cite references for merging of bird species. Also, I think such arguments should be added to most recent common ancestor. Notice that Mitochondrial Eve article already discusses this topic.

I am nominating the species integration for deletion (see its talk page). Thus I don't believe this paragraph is appropriate at this time in this articl. Fred Hsu 23:20, 4 August 2007 (UTC)

Even if the 'word phrase' is eliminated, the concept of 'multiple origins' is the basis of the multi-regional hypothesis. Given that the 'identical ancestors point' is contingent upon ideas widely perceived to be 'true' but which remain UNPROVEN, I find room to insert a 'caveat' into the article. Indeed, it was questions about the 'wobbling' of planets that led to the discovery of Pluto. However, it turned out that the 'wobbling' was an errant calculation--but fixing this calculation helped validate the theory of relativity. Questioning loopholes in scientific theory is an integral part of ensuring that we have the 'right answers', rather than simply being 'in the ballpark.'Ryoung122 09:48, 7 August 2007 (UTC)
If my understanding of multiregional hypothesis is correct, this theory does not claim that modern human was a result of merging of multiple non-breeding species. Instead, the theory states that basically the various descendant groups of Homo erectus (including Neanderthal) are all one interbreeding species. It states that all these groups (one species) evolved around the world into Homo sapiens sapiens via frequent breeding around borders of regions. If so, the calculation for MCRA and identical ancestors point is still perfectly valid for the multiregional hypothesis, as all such hominids are one single happy breeding species. Fred Hsu 16:22, 7 August 2007 (UTC)

[edit] Versus MRCA

The information held on Identical Ancestor Point appears to be questionable. .14:28, 17 August 2007 (UTC) 86.147.2.137 14:41, 17 August 2007 (UTC)

You are probably thinking about matrilineal MRCA. Please see explanation at Mitochondrial Eve. I'll add a few words to this article as well to clarify this. No, it's not an error. Fred Hsu 02:10, 18 August 2007 (UTC)

[edit] I don't get it.

I don't get it.

Is IAP a theory, a statistical probability or is it a mathematically proven fact (like mitochondrial eve)? Is it a DNA inference, a population theory or is it an obvious fact that I do not see?

Let's imagine that some geographical or continental isolation event happened at the estimated time of the IAP dividing the population. Two siblings were thus separated. The parents and entire lineage of these two individuals may obviously have a probability of being a common ancestor. But what is it that makes all their contemporaries as either with terminated line of descent or a common ancestor to BOTH populations?

I don't get it.

The article seems to give the arguement that as you go back, a bigger and bigger percentage of the population will be implicated, but why can't this be a converging trend?

What observable evidence is it that would separate these two scenarios?

I feel stupid for asking this, so bear with me. —Preceding unsigned comment added by 195.139.24.169 (talk) 12:35, 18 April 2008 (UTC)

[edit] What this article needs now

1. Some simple examples of what is being discussed (such as given in last common ancestor)

2. A diagram or two

3. Rewriting for style and clarity.

I would give this last a go now, but I'm a bit hazy on some of the details. If no one has done it in a couple of weeks, I will attempt it. Myles325a (talk) 04:02, 10 May 2008 (UTC)