Jump to content

Talk:Lake Mungo remains

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Propose deletion of the following section

[edit]

Material not notable enough to be included.

  • Result of one study
  • Represented only part of the HVR1
  • The sequence matched in part to Haplogroup M HVR sequence (4 nucleotides) which human mtDNA MRCA does not bear (IOW it was derived in the same direction as Haplogroup M).
  • The additional mutations (11) on the sequence are similar in form see in other sequence errors from the period, and also see in sequencing of ancient DNA from Mexico (White Mountain, Mexico never published)
  • Was a Haplogroup M DNA with alot of derivations or sequence errors, or an ancient DNA that was contaminated by a sequencer with Haplogroup M.
  • The additional mutations were C/T rich indicating they were likely due to post mortem cytosine deamination. PB666 yap 07:07, 13 September 2009 (UTC)[reply]

Mitochondrial DNA study

[edit]

In a study conducted by Australian National University graduate student Greg Adcock and others in 1995[1], mitochondrial DNA was collected from bone fragments from LM3's skeleton and analysed. The mtDNA was compared with samples taken from several other ancient Australian human skeletons, a Neanderthal mtDNA sequence, modern day living Australian Aborigines, and other living humans. The results showed that despite being anatomically within the range of fully-modern humans, LM3 was descended from a different direct maternal ancestor than the most recent common ancestor in the female line of all living humans, the so-called "Mitochondrial Eve". His mtDNA is not entirely extinct, however, as a segment of it is found inserted in nuclear chromosome 11 of many people today.

The study has been controversial because it is claimed to present a challenge to the "Recent Out of Africa" theory of human evolution, which holds that all humans are entirely descended from common ancestors who originated in Africa within the last 200,000 years. The study authors proposed that their results support the multiregional hypothesis, which holds that traits of modern humans evolved in several places around the world, and that gene flow created the genetic uniformity seen today, not a recent migration of a single population from Africa.

However, this is not in conflict with the Out of Africa model, as the Mitochondrial Eve mtDNA type and the LM3 mtDNA type may have both spread from Africa, with one maternal line going extinct and one surviving to today. The time of the split between Mitochondrial Eve and LM3's maternal ancestor must have been earlier than the date when the main wave of fully modern humans left Africa, about 50,000 - 60,000 years ago.

Since remains of a robust form of modern humans have been found in Ethiopia dating to about 160 ka, and similar remains have been dated at Jebel Qafzeh in Israel at about 100 ka, it is conceivable that LM3's maternal ancestor left Africa in an early wave. Indeed, Schillaci has recently found morphological similarities among the crania of early humans of the Levant and those of Australasia [1].

The study by Adcock has been criticized by a study conducted by Chris Stringer. Adcock claimed to have found an exceptionally large amount of ancient DNA from the Mungo remains. This finding is inconsistent with other researchers who were searching for Neanderthal DNA. The study indicates that Ancient DNA is most likely preserved in cold environments such as those found in Europe. But even in the case of Neanderthal remains, the probability of extracting DNA is still low. The study further indicates that the likelihood of any DNA being preserved over the 40,000 - 60,000 years since the Mungo burial is very low. [2]

References

  1. ^ Schillaci, Michael (2008). "Human cranial diversity and evidence for an ancient lineage of modern humans". Journal of Human Evolution. 54 (6): 814–826. doi:10.1016/j.jhevol.2007.10.010. {{cite journal}}: Cite has empty unknown parameter: |coauthors= (help); Unknown parameter |month= ignored (help)
  2. ^ Chamberlain, C (2003). "The thermal history of human fossils and the likelihood of successful DNA amplification" (PDF). Journal of Human Evolution. 45: 203. doi:10.1016/S0047-2484(03)00106-4.

The above "critique" lack consideration about preservation of ancient DNA in MM specimen paleo-environment. Further reading (to do) - what was that environment ? However tacking unrelated specimens may have make some sense for so called "science" 76.16.183.158 (talk) 12:00, 13 September 2009 (UTC)[reply]

The environment varied from lakeside to arid desert generally hot and not well adapted to the preservation of DNA. There were several critiques written, here is one.[1][2] The most important point;however, Adcock presented a Sequence, that by HVR-region is similar to L1. Therefore the only conclusion that they could draw is either tha boo-booed or that are large number of HVR mutations occurred in a very short time. The evidence speaks now from several papers that this sequence was in error, and I personally don't think wikipedia is a place were we present one weak finding and then go about shooting it down with 100 bullets.PB666 yap 17:17, 14 September 2009 (UTC) Also:[reply]

We suggest that postmortem damage may explain many unusual results obtained from ancient human remains when appropriate techniques were not followed (e.g., the 60,000-year-old “Mungo man” sequences; Adcock et al. 2001). Postmortem damage will also complicate population genetic analyses of ancient humans, and detailed cloning will be needed to avoid overestimation of heterogeneity and population expansion sizes (Lundstrom et al. 1992; Aris-Brisou and Excoffier 1996).

— Gilbert et al 2003

Note the Date range for the site is between 40 and 65,000 years ago, the overlap of confidence ranges based on various dating techniques is between 50 and 55kya. This is a quote from Nature 1972 regarding the LM1 site:

During the late pliestocee the fresh waters of the lakes attracted early man and the lunettes built up on their north-eastern shores provided a favourable environment for preserving traces of occupation. Lake Mungo, one of a chain of lakes in south-western New South Wales is now dry and its lunette is eroding and yeilding anceint Aboriginal[sic] relics.

— Barbetti and Allen 1972, Nature 240, page 46-48

References

  1. ^ ">Smith CI, Chamberlain AT, Riley MS, Stringer C, Collins MJ (2003). "The thermal history of human fossils and the likelihood of successful DNA amplification". J Hum Evol. 45 (3): 203–217. PMID 14580590.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ Cooper A, Poiner HN (2000). "Ancient DNA: Do It Right or Not at All". Science. 289 (5482): 1139. doi:10.1126/science.289.5482.1139b. PMID 10970224.

Adcock Sequence versus human consensus

[edit]

Adcock's paper was published in 2001 after the first genomic mtDNA study, since then better studies have been published, one can derive sequence, In addition the Neandertal specimen used underwent genomic sequencing, four of the sites CRS# Hs . . . P1. . . P2 16107 C . . . T . . . C 16108 C . . . T . . . C 16111 C . . . T . . . C 16112 C . . . T . . . C P2 is the genomic feldhofer 1 and P1 is Krings et al 1997 feldhofer 1.

I have removed all the other sequences for chimpanzees and Neandertals to simplify Table 1 of Adcock et al. 

         1 1 1 1 1 1 1 1 1 1 1 1
         6 6 6 6 6 6 6 6 6 6 6
         1 2 2 2 2 2 2 2 3 3 3
         6 0 2 5 6 6 7 9 1 5 8
         3 1 3 3 3 4 4 0 1 6 7
L1       A C T A T C G C C T A
LM55 (4) G - C - - T - - T - -
LM15 (3) - - - - - - - - T C G
LM3  (7) - - - - C T A T T C G
LM4  (3) - T C G - - - - - - -

Adcock used CRS for a comparison however CRS is a NW European sequence not an austronesia. Since I don't want to bias the argument, all known Eurasian sequences except a few scattered about the middle east proximal to Africa are derivatives of L1, therefore and L1 concensus was used to align the above. LM3 only differed from L1 at 7 positions. The average depth of the mtDNA tree is 6 and for HVR1 no positions can be resolved lower than the basal branches of L0 or L1 (thats why L0 and L1 trees were not resolved until genomic sequencing was done). Consequently its really a measure to the basal L1 or L0 branches. In the pattern above LM3 appears to be a derivative of LM15 which appears to be a derivative of L1. LM55 appears to have the base (16311T) mutation although 16311 is one of the superhypervariable sites noted in Excoffier and Wang. Adjacent mutations such as 16263 and 16264 are suspicious, and frequently reflect sequencing errors (See above for feldhofer 1).

The binomial probability distribution states that in N selections the probability of arriving at X when Y is expected can be predicted. The probability of 7 mutations when 4.3 are expected is 0.12 and 4.3 of 6 mutations are expected from good sequence of 40kya. Consequently there is nothing above that supposes this sequence is of a different origin than other human sequences.

The Neanderthal alignment (Neandertal variable with basal L1) is given below. 

                     1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
                     6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 
                     0 1 1 1 1 1 1 1 2 2 2 2 2 2 3 3 
                     7 3 4 5 6 8 8 9 0 3 4 5 5 6 2 6 
                     8 9 8 4 9 3 9 9 9 4 4 6 8 2 0 2 
L1                   A A C T C A T T T C G C A C C T 
LM3                  A A C T C A T T T C G C A C C T
Bonobo               A T C T T A C C A A A A A C T C 
Chimpanzee           A T T T C A A A C A A A A C C T 
Feldhofer 1          G T T C T - C C C T A A G T T C

LM3's sequence matches human at every position. The deviancies between LM3 and Human-CRS are due to direction evolution of CRS away from both the concensus human and Neanderthal. Consequently it makes no sense at all to refer to this as a Neandertal Sequence, particularly in light of the recent presentation in PNAS for September basically arguing that Neandertals should be treated as a separate species.

name of this article

[edit]

Why is this article called "Mungo Lake remains"? The popular and official name of the place is Lake Mungo, not Mungo Lake. McKay (talk) 04:29, 12 April 2011 (UTC)[reply]

There being no objection, I'm moving it. McKay (talk) 05:33, 20 May 2011 (UTC)[reply]


Multiregional

[edit]

"Comparison of the Mitochondrial DNA with that of ancient and modern Aborigines has indicated that Mungo Man is not related to Australian Aborigines. The results indicate that Mungo Man is an extinct subspecies that diverged before the most recent common ancestor of contemporary humans. These results, if correct, supports the multiregional origin of modern humans hypothesis."

I don't really see how. If these remains _were_ related to some modern humans, it would support the MR hypothesis. Given that they aren't, the Out Of Africa hypothesis still applies to all modern humans. Ordinary Person (talk) 01:33, 26 November 2011 (UTC)[reply]

- Sounds like a case of trying to fit the evidence in around the theory rather than the theory around the evidence. LM3 is a variety of homo sapiens, just because it has no proven living decedents doesn't mean it should be ignored, no matter how much of a spanner in the works it is to OOA theory. Cerumol2 (talk) 10:01, 24 April 2012 (UTC)[reply]

One migration out of Africa or two?

[edit]

The article says that all non-African humans are descended from a single migration out of Africa 60KYA. Doesn't the work of Cavalli-Sforza and others identify two migrations?

The first was 60KYA, at the depth of an ice age when rainfall was low and there was a famine in Africa. This first band of migrants kept going east and eventually settled in Australia. This was not a difficult voyage with stone-age boating technology, since sea level was much lower and the straits between the islands were much narrower. Due to the vagaries of weather patterns, Australia was a paradise.

The second migration, according to Cavalli-Sforza (IIRC), was about 10,000 years later. There was no famine so these people were perhaps simply adventurous. They settled in southwestern Asia and eventually their descendants populated Eurasia and the Americas. His maps, based on DNA analyses of hundreds of people all over the globe, even show their convoluted migration routes. He seems to have been the first to identify the close relationship between the Navajo and the Yenisei, which preceded (or perhaps inspired) the linguists whose analysis suggests the same thing.

Cavalli-Sforza says that the Native Australians have distinctly different DNA from the rest of us, although both are clearly of San lineage. He also claims to have found people along the coast of India who have traces of Native Australian DNA, illustrating the route taken by their ancestors but pushed inland by rising sea levels. He says that the chronology indicates that this hybridization occurred tens of thousands of years ago, rather than in historical times when adventurous Australians might have gone exploring in more modern craft. — Preceding unsigned comment added by Gene Fellner (talk • contribs) 17:38, 2 May 2013 (UTC)[reply]

General improvements

[edit]

The article needs more pictures depicting its subjects. And some of the links (e.g. [5] - Brown, Peter Lake Mungo 1 University of New England) are 404ing. — Preceding unsigned comment added by 203.206.21.233 (talk) 08:02, 21 February 2015 (UTC)[reply]

Surely this sentence needs revision

[edit]

"The current mainstream thinking, the recent African origin of modern humans model, suggest that all humans alive today descended from a small group, which left Africa at a specific time, currently generally estimated at about 60,000 years ago." But surely most present day Africans are not descended from this "small group". Perhaps, or perhaps not, we could correctly revise it to say that present day African people are descended from humans closely related to that "small group"? In any case, I'm sure the current sentence is wrong.2601:7:6580:5E3:EDCC:FF76:57F3:144B (talk) 02:22, 18 April 2015 (UTC)[reply]

Oldest Anatomically Modern human in Australia?

[edit]

This line seems to imply the existence of archaic humans in Australia pre-dating LM3. Are there any reliable sources for such finds? — Preceding unsigned comment added by 70.162.195.68 (talk) 00:07, 3 March 2016 (UTC)[reply]

Speculation about burial rituals

[edit]

Are there more ideas about the cremation, how it happened, and why? There's one unsourced thought on this page. Perhaps that speculation should be removed or other ideas could join it. — Preceding unsigned comment added by 96.42.57.184 (talk) 08:59, 27 November 2016 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just modified 2 external links on Lake Mungo remains. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 20:05, 10 May 2017 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just modified 6 external links on Lake Mungo remains. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 22:01, 15 December 2017 (UTC)[reply]

Megafuuna decline and date of remains.

[edit]

The date of the remains dose coincides with the rapid Extinction of Australian megafauna. — Preceding unsigned comment added by Geo1un (talk • contribs) 05:44, 24 June 2018 (UTC)[reply]

LM2

[edit]

Why no information about LM2? 104.153.40.58 (talk) 14:56, 19 June 2021 (UTC)[reply]

Retrieved from "https://en.wikipedia.org/w/index.php?title=Talk:Lake_Mungo_remains&oldid=1208080241"