Now it is generally accepted, as Rational Wiki puts it, that “If two organisms share the same ERV, in the same location, with the same inactivation mutations, then they almost certainly share them due to common inheritance and not two separate infections.” But I have to disagree. This is an assumption!
Their use of the phrase “not two separate infections” IMO is deceptive, because the same infection, in two similar species during the exact time frame, would produce the exact same results that we observe, and therefore it would not be necessary that they be two “separate” infections at all (they are implying this is a claim that has been made, though I searched and could not find it...if one of you do please post a reference or a link) and would thus NOT imply an assumption of common descent.
In my humble opinion, because researchers seek these alleged ERVs out to form or prove phylogenetic trees, lineal relationship is already a pre-supposed conclusion before they assume or seek (which biases the interpretation).
Madalina Barbulescu in, “A HERV-K Provirus in Chimpanzees, Bonobos, and Gorillas, but Not Humans,” Current Biology 11 (May 2001): 779–83, doi:10.1016/S0960-9822(01)00227-5, tells us that some of the ERVs found in chimps, bonobos, and gorillas, are not present in humans and many in humans are not found in any of the others (also see Chris T. Yohn et al., “Lineage-Specific Expansions of Retroviral Insertions within the Genomes of African Great Apes but Not Humans and Orangutans,” PLoS Biology 3, April 2005: e110, 10.1371/journal.pbio).
In light of this, Molecular Biologist, Dr. Anjeanette Roberts believes “the longer I think about ERVs and viral origins, and as I observe scientific reports identifying various critical functions associated with ERVs and other repetitive genomic elements, I believe it may be profitable for driving scientific inquiry to question some of the underlying assumptions that support ERVs as inarguable signs of common descent.”
A study done by Catriona M. Macfarlane and Richard M. Badge, (“Genome-Wide Amplification of Proviral Sequences Reveals New Polymorphic HERV-K(HML-2) Proviruses in Humans and Chimpanzees that are Absent from Genome Assemblies,” Retrovirology 12 (April 2015): id. 35, doi:10.1186/s12977-015-0162-8) implies we may need to re-think the time element generally assumed because mounting evidence indicates a much more recent insertion event for humans than for chimps at many shared ERV insertion sites previously thought to confirm common ancestry.
So from this, simple logic tells us that IF that is true in those samples they examined, THEN it could also be true in other cases (which means the evidence used in these sites no longer can be said to indicate descent). Same insertion, in the same place, yet at two different times, to two different creatures (possibly not related except via taxonomic convention).
So I could also ask (rhetorical, no need to answer), “Does this really prove Common Descent or is that possibility already assumed?” Or even “Perhaps these allegedly similar genomes show a sort of biochemical preference as to where such materials would be placed?” Hmmm? If this case were true, maybe the genome plays a role in selecting which ones may be useful.
Their use of the phrase “not two separate infections” IMO is deceptive, because the same infection, in two similar species during the exact time frame, would produce the exact same results that we observe, and therefore it would not be necessary that they be two “separate” infections at all (they are implying this is a claim that has been made, though I searched and could not find it...if one of you do please post a reference or a link) and would thus NOT imply an assumption of common descent.
In my humble opinion, because researchers seek these alleged ERVs out to form or prove phylogenetic trees, lineal relationship is already a pre-supposed conclusion before they assume or seek (which biases the interpretation).
Madalina Barbulescu in, “A HERV-K Provirus in Chimpanzees, Bonobos, and Gorillas, but Not Humans,” Current Biology 11 (May 2001): 779–83, doi:10.1016/S0960-9822(01)00227-5, tells us that some of the ERVs found in chimps, bonobos, and gorillas, are not present in humans and many in humans are not found in any of the others (also see Chris T. Yohn et al., “Lineage-Specific Expansions of Retroviral Insertions within the Genomes of African Great Apes but Not Humans and Orangutans,” PLoS Biology 3, April 2005: e110, 10.1371/journal.pbio).
In light of this, Molecular Biologist, Dr. Anjeanette Roberts believes “the longer I think about ERVs and viral origins, and as I observe scientific reports identifying various critical functions associated with ERVs and other repetitive genomic elements, I believe it may be profitable for driving scientific inquiry to question some of the underlying assumptions that support ERVs as inarguable signs of common descent.”
A study done by Catriona M. Macfarlane and Richard M. Badge, (“Genome-Wide Amplification of Proviral Sequences Reveals New Polymorphic HERV-K(HML-2) Proviruses in Humans and Chimpanzees that are Absent from Genome Assemblies,” Retrovirology 12 (April 2015): id. 35, doi:10.1186/s12977-015-0162-8) implies we may need to re-think the time element generally assumed because mounting evidence indicates a much more recent insertion event for humans than for chimps at many shared ERV insertion sites previously thought to confirm common ancestry.
So from this, simple logic tells us that IF that is true in those samples they examined, THEN it could also be true in other cases (which means the evidence used in these sites no longer can be said to indicate descent). Same insertion, in the same place, yet at two different times, to two different creatures (possibly not related except via taxonomic convention).
So I could also ask (rhetorical, no need to answer), “Does this really prove Common Descent or is that possibility already assumed?” Or even “Perhaps these allegedly similar genomes show a sort of biochemical preference as to where such materials would be placed?” Hmmm? If this case were true, maybe the genome plays a role in selecting which ones may be useful.
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