Controversies in Science/Was there a mitochondrial Eve?

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(from Controversies in Science)

Was there a mitochondrial Eve?

Points For[edit]

The Coalescence Theory[edit]

The Mitochondrial Eve is supported by the Coalescence Theory which is a group of branch processing theorems about genetic behaviour. The Coalescence Theory predicts the variation between descendants of a common ancestor after several generations.[1].

Did the Mitochondrial Eve live 200,000 Years Ago?[edit]

A study at Rice University, conducted sometime in 2010, determined/confirmed that the Mitochondrial Eve "Mother of all humans" lived 200,000 years ago. Scientist at Rice University have been comparing a number of human genetic models to determine Eve's genetic past and learn more about genetic mutations. [2]

The theory of a Mitochondrial Eve is supported by anthropological evidence[edit]

However, it is a theoretical explanation to address current confusion between group genealogies and individual genealogies. More research needs to be conducted, but the evidence does seem to point to a specific point of divergence towards the evolution of modern human beings. [3]

All living individuals originate from the same common ancestor[edit]

The Coalescence Theory provides more evidence that genetic behavior has a common ancestor from one original mother, dated back around 200,000 years ago. Through the rigorous study of mtDNA, there is strong mathematical evidence supporting that the mtDNA organisms are maternally transmitted and have common genetic behaviors. Essentially, humans have mutated from one being to the next carrying the same gene through each generation.[4].

We Are Not Diverse Enough[edit]

Humans do not come from multiple different origins, as research shows they are all very similar to each other. Years ago, there must have been one single origin for all human kind. There is a plethora of mathematical evidence to back this up. The lack of variation in the DNA indicates that humans come from a recent ancestor, not multiple ancestors.[5]. The only differences between humans are superficial. The lack of differences amongst humans indicates that the most recent common ancestor was not that long ago.[6].

We Originated in Africa & We All Originated From The Same mtDNA[edit]

Modern day people orginated from Africa and travelled their way around the world. Paleobiological and archeological evidence support the argument that humans might have first originated approximately 196,000 years ago, in East Africa.[7]

Neanderthal and Human mtDNA analysis shows variance in pairwise sequence[edit]

Distribution of human and Neanderthal Pairwise mtDNA Sequence Differences shows that humans and Neanderthals do not share similarities in mtDNA, suggesting that hominids originated from a single source and were not the product of human and Neanderthal cross-breeding. From this, they have determined that the two groups split 660,000 years ago (+ / - 140,000). [8]

The orangutan and African apes separated over 13 million years ago. Humans and chimpanzees separated 4.9 million years ago[9].

Few synonymous changes among human mtDNA support mitochondrial Eve[edit]

There is strong evidence that the Mitochondrial Eve exists because comparison of synonymous changes between African, Japanese, European, Orangutan, Chimpanzee, and Gorilla mitochondrial DNA points to a shallow human ancestry, which suggests that modern humans originate from Africa.[10]

Tracing Origins of Mitochondrial Eve[edit]

Origins of modern day humans can be traced by examining the DNA of mitochondria. The University of California Berkley published a paper based on the premise that they could determine how closely people of different ethnic backgrounds are related by comparing mitochondrial DNA and creating ancestral branches[11].

Relationship Between Humans and Neanderthals[edit]

Mitochondrial DNA helps prove the relationship between human beings and Neanderthals. This DNA also proves important events in history, such as the expansion of the Neolithic farmers who expanded into Europe [12].

Steve Olsen and Mapping Human History[edit]

"Only about 6,000 generations separate everyone alive today from a common set of ancestors," -Steve Olsen. In Steve Olsens’ book, "Mapping Human History: Discovering the Past Through Our Genes", he interviews many scientists that add proof to the expansion over 4 continents. i.e.) Africa, The Middle East, Asia and the pacific ocean. The traveling our ancestors did is described through the several visits he takes to each continent. The study of genes proves the large quantities of important and historical information hidden inside each strand of DNA. He bring up the matter of identical twins; they may be identical but they both have differences in their genetic code due to mutations[13].

Modern Homo Sapiens lived in Africa at the same time as Neanderthals in other parts of the world[edit]

By analyzing the transformations and substitutions of the D-loop segment of mDNA we can see an overlap in time when Homo Sapiens in Africa lived as well as the Homo Erectus in the rest of the world. Therefore, the Homo Sapiens in Africa were not a result of interbreeding. [14]

Points Against[edit]

Modern Day Humans Originate From Many Different Sources[edit]

Multiregional Evolution suggests that modern day humans originated from many different kinds of species. It has been shown that humans today have many different genetic characteristics, from many different sources. This also means, humans today have come from more than only early African heritage. [15]

Multi Regional Theory[edit]

The multiregional theory argues that our earliest ancestors came from out of Africa. These ancestors then migrated from Africa to different parts of the world through gene flow and natural selection[16].

Diverse modern human immune systems have acquired characteristics from multi-regional descendence[edit]

A study into a specific leukocyte antigen shows that we inherited certain alleles from interbreeding with the Denisovan humans ( a sister group to the better known neanderthals) that has introgressed into the genome of modern Eurasians and Oceanians. [17]

Multiple Sources of Genetic Information[edit]

There was restricted but recurrent gene flow among prehistoric human populations in various regions of the Old World, contradicting the theory that there was one single mother of all humans today[18].

There is fossil evidence to prove differences between date estimates for the Mitochondrial Eve[edit]

There are differences between information presented as "evidence" as to when the Mitochondrial Eve began and where it's origins are[19]

Breaking News: Your data size is too small[edit]

The Monte Carlo simulation shows that the current data has been misinterpreted because the sample size is so small. Mitochondrial DNA can be interpreted and limited just to Africa; however, based under the assumption that there are multiple regions, the Monte Carlo simulation shows that this theory is flawed. [20]

In addition, methods that prove the mitochondrial Eve are large in variation and accommodate several alternative matrices, as well as many revolutionary assumptions. The analysis has never been modified in any advanced aspect and is very basic in nature. [21]

History shows that only heuristic run has ever been completed with a single variation of mtDNA restriction-site data, tried by Cann, Stoneking, and Wilson (1987). As a result, the maximum parsimony tree was not found giving less than credible data. Sequence data created by Vigilant et al. (1991) proved similar results. [22]

Mit-no-chondrial[edit]

Mitochondrial Eve can be pushed back to two million years ago based on the findings of shared DNA with earlier species of humans. As much as 80% of our DNA is shared with them, which proves we have been interbreeding for longer than was originally thought. [23]

One main source of error is the evolutionary process. The stochastic process was greatly affected by the genetic drift which directly related to a skewed genetic variation proving that mtDNA did not take all factors into consideration. [24]

Evidence for mitochondrial DNA recombination in a human population of island Melanesia[edit]

Their DNA type was found to be a recombination of mtDNA types of individuals in other remote areas which is highly unlikely. [25].

Absence of Regional Affinities of Neanderthal DNA With Living Humans Does Not Reject Multiregional Evolution[edit]

The evidence for a Mitochondrial Eve neglect to consider migration and inter-marriage patterns. [26]

Mitochondrial Eve Hypotheses Flaws[edit]

Mitochondrial Eve is a hypothesis, which states that humans today are created from a common female ancestor. This suggests that all modern humans are from the same geographical population as the common ancestor. The female ancestor is of African origin and lived 200,000 years ago. The phylogeny of mtDNA is also of that population; the modern human came from Africa and spread across the world to wipe out the homo humans to extinction. These hypotheses are wrong.[27].

Anatomical Evidence[edit]

Anatomical evidence for the multiregional theory suggests that human evolution evolved through genetic drift and natural selection. Different ancestors like the Neanderthal, which are found in Europe and Asia, had specific features such as larger brow ridges, massive facial skeleton, and long clavicles, just to name a few. This theory helps undermine the Mitochondrial Eve hypothesis[28].

[29]===Archeological Evidence=== There was a diversity of stone tool technology found on different continents. There could of been interbreeding between populations.

References[edit]

  1. De Oliviera, P., M., C., De Oliviera, S., M., Radomski, J., P. (2001). Simulating the mitochondrial dna inheritance. Theory in Biosciences, 120(2), 77-86. doi: 10.1007/s12064-001-0008-x Retrieved from http://library.mtroyal.ca:2088/content/j28133773h623025/abstract/
  2. http://www.sciencedaily.com/releases/2010/08/100817122405.htm
  3. Ayala,F. (1995). The Myth of Eve: Molecular Biology and Human Origins. Science, New Series.Vol. 270,No. 5244,1930-1936. Retrieved November 16, 2010 from http://www.ecologia.unam.mx/laboratorios/evolucionmolecular/viejo/talleresycursos/genpob/arts/16_Ayala_1995.pdf
  4. De Oliviera, P., M., C., De Oliviera, S., M., Radomski, J., P. (2001). Simulating the mitochondrial dna inheritance. Theory in Biosciences, 120(2), 77-86. doi: 10.1007/s12064-001-0008-x Retrieved from http://library.mtroyal.ca:2088/content/j28133773h623025/abstract/
  5. Excoffier, L. (2002) Human demographic history: refining the recent African origin model. Current opinion in genetics & development (0959-437X), 12 (6), 675. DOI: 10.1016/S0959-437X(02)00350-7 http://www.sciencedirect.com/science/article/pii/S0959437X02003507
  6. Olson, S. (2002). Mapping Human History. Houghton Mifflin Company./
  7. Gonder, M., Mortensen, H., Reed, F., de Sousa, A., & Tishkoff, S. (2006)."Whole-mtDNA Genome Sequence Analysis of Ancient African Lineages". Whole-mtDNA genome sequence analysis of ancient African lineages. Molecular Biology and Evolution, 24(3), 757-768. doi:10.1093/molbev/msl209 http://library.mtroyal.ca:2048/login?url=http://dx.doi.org/10.1093/molbev/msl209
  8. Green, R., Malaspinas, A., Krause, J., Briggs, A., Johnson, P., Uhler, C…. Paabo, S. (2008) " A complete Neanderthal Mitochondrial genome sequence determined by high-throughput sequencing: A Review". Cell. 134(3) pg. 416-426. Retrieved March 22, 2011. From: http://library.mtroyal.ca:2048/login?url=http://dx.doi.org/10.1016/j.cell.2008.06.021
  9. http://library.mtroyal.ca:2048/login?url=http://dx.doi.org/10.1016/j.cell.2008.06.021
  10. Horai, S., Hayasaka, K., Kondo, R., Tsugane, K., & Takahata, N. (1995). Recent African origin of modern humans revealed by complete sequences of hominoid mitochondrial DNAs. Proceedings of the National Academy of Sciences of the United States of America, 92, 532-536. Retrieved on March 22, 2011, from http://www.pnas.org/content/92/2/532.short
  11. ProQuest Research Library (1992),Mitochondrial Eve: Wounded, but not dead yet,pg. 873
  12. Hagelberg E, (2003) Recombination or mutation rate heterogeneity? Implications for Mitochondrial Eve. Trends and Genetics, 19,2
  13. http://www.houghtonmifflinbooks.com/booksellers/press_release/olson/olson_mapping.pdf.
  14. G Pesole, E Sbisá, G Preparata and C Saccone. The Evolution of the mitochondrial D-loop and the origin of Modern Man. Oxford Journals Life Sciences & Mathematics & Physical Sciences & Medicine Molecular Biology and Evolution Volume 9, Issue 4,587-598 http://mbe.oxfordjournals.org/content/9/4/587.
  15. Eswaran, V., Harpending, H., & Rodgers, A. R. (2005). Genomics refute an exclusively African origin of humans. Journal of Human Evolution, 49, 1-18. http://dx.doi.org/10.1016/j.jhevol.2005.02.006.
  16. Johnson, D. (2001). Origins of modern multi regional or out of Africa? 1-8
  17. Abi-Rached L, Jobin MJ, Kulkarni S, McWhinnie A, Dalva K, Gragert L, Babrzadeh F, Gharizadeh B, Luo M, Plummer FA, Kimani J, Carrington M, Middleton D, Rajalingam R, Beksac M, Marsh SG, Maiers M, Guethlein LA, Tavoularis S, Little AM, Green RE, Norman PJ, Parham P. (2011). a critique of: The shaping of modern human immune systems by multiregional admixture with archaic humans.Science. 334(6052):89-94. PDF link
  18. The "Eve" Hypotheses: A Genetic Critique and ReanalysisThe "Eve" Hypotheses: A Genetic Critique and Reanalysis.American Anthropologist 95, (1 ) 51-72 . Retrieved on March 22 from ,http://library.mtroyal.ca:2048/login?url=http://www.jstor.org/stable/681179
  19. Ho, S., Larson, G. (2006) Molecular clocks: when timesare a-changin'. Trends in Genetics 22(2),79–83.
  20. Eswaran, V., Harpending, H., & Rogers, A. (2005). Genomics refutes an exclusively African origin of humans Journal of Human Evolution, 49(1), 1-18. Retrieved from http://www.sciencedirect.com/science/article/pii/S0047248405000357
  21. L. Excoffier, P.E. Smouse and J.M. Quattro (Center for Theoretical and Applied Genetics (CTAG), Cook College, Rutgers University, New Brunswick, New Jersey 08903-0231, Department of Anthropology and Ecology, University of Geneva, 1227 Carouge, Switzerland) Analysis of Molecular Variance Inferred From Metric Distances Among DNA Haplotypes: Application to Human Mitochondrial DNA Restriction DataGenetics, Vol 131, 479-491, Copyright © 1992 http://www.genetics.org/content/131/2/479.short
  22. Alan R. Templeton, The "Eve" Hypotheses: A Genetic Critique and Reanalysis, 53 (2-3). American Anthropologist © 1993 American Anthropological Association http://www.jstor.org/stable/681179?seq=3
  23. Eswaran, V., Harpending, H., & Rogers, A. (2005). Genomics refutes an exclusively African origin of humans. Journal of Human Evolution, 49(1), 1-18. Retrieved on November 15, 2011 from http://www.sciencedirect.com/science/article/pii/S0047248405000357
  24. Alan R. Templeton, The "Eve" Hypotheses: A Genetic Critique and Reanalysis, 57 (2). American Anthropologist © 1993 American Anthropological Association http://www.jstor.org/stable/681179?seq=3
  25. agelberg. E., Goldman N., Lio P., Whelan S., Schiefenhovel W., Clegg J. B. & Bowden K. D. (1998).Evidence for mitochondrial DNA recombination in a human population of island Melanesiaagelberg. E., Goldman N., Lio P., Whelan S., Schiefenhovel W., Clegg J. B. & Bowden K. D. (1998). The Royal Society.266, 485-492. Doi: 10.1098/rspb.1999.0663 from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1689791/pdf/10189712.pdf
  26. Relethford, J. (2001) Absence of Regional Affinities of Neandertal DNA With Living Humans Does Not Reject Multiregional Evolution, American Journal of Physical Anthropology 115, 95–98 http://ejscontent.ebsco.com/ContentServer.aspx?target=http%3A%2F%2Fonlinelibrary.wiley.com%2Fresolve%2Fdoi%2Fpdf%3FDOI%3D10.1002%2Fajpa.1060
  27. Templeton, A.R. (1993) The "Eve" Hypotheses: A Genetic Critique and Reanalysis.American Anthropologist 95, (1 ) 51-72 . Retrieved on March 22 from ,http://library.mtroyal.ca:2048/login?url=http://www.jstor.org/stable/681179
  28. Johnson, D. (2001). The Origins of Modern Humans: Multiregional or Out of Africa? 1-8
  29. John,D (2001) Origins of moderm humans: Multiregional or out of Africa? 1-8