Human paleontologists are unable to extricate species-level variation from individual, sexual, ge... more Human paleontologists are unable to extricate species-level variation from individual, sexual, geographical, pathological, and skull bone variations despite sophisticated statistical methodology. Additionally, true variation within and between groups cannot be generated from a handful of regional and geographical specimens presently used in comparative studies. I therefore conclude that we cannot identify species in the human paleontological record. This conclusion is supported by the analysis and discussion (in this paper) of research conducted on, what I deem to be, three high-profile genus Homo fossil discoveries: Dmanisi hominins, Homo floresiensis, and Homo naledi. The data compiled in these comprehensive studies conclude that Dmanisi, floresiensis, and naledi share features with all Homo and Australopithecine taxa. Specifically, none of these three fossils clustered or aligned definitively with any Homo specimens. Consequently, it may now be prudent for us to use numbers or look for gross similarities and differences in hominin fossils to classify them. As such, identifying fossils at the genus level, which was proposed recently, might be a solution worth considering. Using genera will reduce the specificity needed in species identification, but it might be preferable to the chaos we have now in species-level identification. This paper is published in two parts.
... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and ... more ... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and the staff in the human paleontology division at the Natural History Museum, London, for all their efforts to accommodate me. Finally, I would ...
Homo-journal of Comparative Human Biology, Jul 1, 2009
The species problem is one of the most complex and enduring problems plaguing evolutionary biolog... more The species problem is one of the most complex and enduring problems plaguing evolutionary biology in general and human paleontology in particular. In the past 50 years, conceptions of species have diverged and speciated analogous to the present, largely accepted view of the hominin phylogeny. Conventional wisdom supports a ''bushy'' hominin phylogeny. However, chaos reigns because there is no agreed-upon methodology used to delimit species taxa in paleontology. This dispute is complicated by the ever-present intraspecific and interspecific morphological variation, which is itself exacerbated by other types of variation, including behavioral, ecological, geographical and temporal. When two or more of these forms of variation are used to delimit ''new'' extant or fossil species, any decision arrived at might be construed as arbitrary. This paper proposes that temporary cessation in assigning new names should be considered based on several critical problems: (1) the explosion of conceptions of a ''species'' arising from disagreements regarding species definitions, (2) differing interpretations of population variation, which lead to difficulty in interpreting hybridization in nature, leading in turn to the underestimation or overestimation of species, (3) the problem of modes of speciation being confounded with criteria used to distinguish among species, e.g., punctuated equilibrium posits high-speciation rates, and (4) the most common of all human traits, vanity.
In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analys... more In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analyses, are accepted as anatomically modern or given the lofty title of Proto-Cro-Magnons. However, their modernity has been questioned in the literature. In this research, 41 dimensions were measured on the crania and 21 dimensions were measured on the femora, tibiae, and innominates of Qafzeh, Skhul, Cro-Magnons, Neanderthals, and other archaic, early, and recent modern samples from Africa, Western Asia, Europe, and East Asia (total crania, N = 400 and total postcrania, N = 1191), to test the null hypothesis that the Qafzeh and Skhul hominids are 'Proto-Cro-Magnons.' Three alternate hypotheses were also tested: (1) the Qafzeh and Skhul hominids have morphometric affinities to one, some, or none of the regional sample groups in this research; (2) the Qafzeh and Skhul hominids are not the same sample; and (3) the Qafzeh and Skhul hominids have morphometric affinities to more archaic sample groups in this research. Canonical variate analysis based on log size/shape and shape D2 for male and female crania show quite clearly that the Qafzeh and Skhul hominids are distant from the Cro-Magnons but closer to African and Levantine sample groups. For females, analysis of the craniofacial variables show that Qafzeh 9 has strong morphometric similarities to the African, Mumba 2. For males, analysis of craniofacial variables show that Qafzeh 6, Skhul 4, and Skhul 5 have respectable morphometric similarities to several archaic moderns but much stronger morphometric similarities, in terms of facial variables, to the North African, Jebel Irhoud 1. Hierarchical cluster analysis presented similar results. Analysis of the male and female postcrania samples show that Qafzeh and Skhul are morphometrically distant from all modern sample groups. Based on the data in this research, the hypothesis that states that the Qafzeh and Skhul hominids are Proto-Cro-Magnons is rejected. Instead, the data support the alternative hypotheses that the Qafzeh and Skhul have strong morphometric affinities to archaic and early modern Africans and Levantines and that postcranially, they are morphometrically distant from all sample groups. Together, Qafzeh and Skhul show strong evidence of mosaic evolution.Ph.D.Biological SciencesBiostatisticsMorphologyPhysical anthropologySocial SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132228/2/9959845.pd
On November 16, 2012, two people searching for cans and bottles in a wooded area off Alden Mounta... more On November 16, 2012, two people searching for cans and bottles in a wooded area off Alden Mountain Road in Newport Township, Luzerne County,
In agriculture, animals and plants are engineered to produce pharmaceuticals, and crops are modif... more In agriculture, animals and plants are engineered to produce pharmaceuticals, and crops are modified to be nutritious, tolerant of herbicides and the natural environment, and resistant to disease. While these goals may seem practical, is it wise to modify plant systems without a clear idea of the long-term effects of genetic engineering in animals and humans? [1].
In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analys... more In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analyses, are accepted as anatomically modern or given the lofty title of Proto-Cro-Magnons. However, their modernity has been questioned in the literature. In this research, 41 dimensions were measured on the crania and 21 dimensions were measured on the femora, tibiae, and innominates of Qafzeh, Skhul, Cro-Magnons, Neanderthals, and other archaic, early, and recent modern samples from Africa, Western Asia, Europe, and East Asia (total crania, N = 400 and total postcrania, N = 1191), to test the null hypothesis that the Qafzeh and Skhul hominids are 'Proto-Cro-Magnons.' Three alternate hypotheses were also tested: (1) the Qafzeh and Skhul hominids have morphometric affinities to one, some, or none of the regional sample groups in this research; (2) the Qafzeh and Skhul hominids are not the same sample; and (3) the Qafzeh and Skhul hominids have morphometric affinities to more archaic sample groups in this research. Canonical variate analysis based on log size/shape and shape D2 for male and female crania show quite clearly that the Qafzeh and Skhul hominids are distant from the Cro-Magnons but closer to African and Levantine sample groups. For females, analysis of the craniofacial variables show that Qafzeh 9 has strong morphometric similarities to the African, Mumba 2. For males, analysis of craniofacial variables show that Qafzeh 6, Skhul 4, and Skhul 5 have respectable morphometric similarities to several archaic moderns but much stronger morphometric similarities, in terms of facial variables, to the North African, Jebel Irhoud 1. Hierarchical cluster analysis presented similar results. Analysis of the male and female postcrania samples show that Qafzeh and Skhul are morphometrically distant from all modern sample groups. Based on the data in this research, the hypothesis that states that the Qafzeh and Skhul hominids are Proto-Cro-Magnons is rejected. Instead, the data support the alternative hypotheses that the Qafzeh and Skhul have strong morphometric affinities to archaic and early modern Africans and Levantines and that postcranially, they are morphometrically distant from all sample groups. Together, Qafzeh and Skhul show strong evidence of mosaic evolution.Ph.D.Biological SciencesBiostatisticsMorphologyPhysical anthropologySocial SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132228/2/9959845.pd
American journal of human biology : the official journal of the Human Biology Council, Jan 10, 2017
We explore variations in body and limb proportions of the Jomon hunter-gatherers (14,000-2500 BP)... more We explore variations in body and limb proportions of the Jomon hunter-gatherers (14,000-2500 BP), the Yayoi agriculturalists (2500-1700 BP) of Japan, and the Kumejima Islanders of the Ryukyus (1600-1800 AD) with 11 geographically diverse skeletal postcranial samples from Africa, Europe, Asia, Australia, and North America using brachial-crural indices, femur head-breadth-to-femur length ratio, femur head-breadth-to-lower-limb-length ratio, and body mass as indicators of phenotypic climatic adaptation. Specifically, we test the hypothesis that variation in limb proportions seen in Jomon, Yayoi, and Kumejima is a complex interaction of genetic adaptation; development and allometric constraints; selection, gene flow and genetic drift with changing cultural factors (i.e., nutrition) and climate. The skeletal data (1127 individuals) were subjected to principle components analysis, Manly's permutation multiple regression tests, and Relethford-Blangero analysis. The results of Manly...
... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and ... more ... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and the staff in the human paleontology division at the Natural History Museum, London, for all their efforts to accommodate me. Finally, I would ...
Proceedings of the National Academy of Sciences, 2005
Many human craniofacial dimensions are largely of neutral adaptive significance, and an analysis ... more Many human craniofacial dimensions are largely of neutral adaptive significance, and an analysis of their variation can serve as an indication of the extent to which any given population is genetically related to or differs from any other. When 24 craniofacial measurements of a series of human populations are used to generate neighbor-joining dendrograms, it is no surprise that all modern European groups, ranging all of the way from Scandinavia to eastern Europe and throughout the Mediterranean to the Middle East, show that they are closely related to each other. The surprise is that the Neolithic peoples of Europe and their Bronze Age successors are not closely related to the modern inhabitants, although the prehistoric/modern ties are somewhat more apparent in southern Europe. It is a further surprise that the Epipalaeolithic Natufian of Israel from whom the Neolithic realm was assumed to arise has a clear link to Sub-Saharan Africa. Basques and Canary Islanders are clearly associ...
Human paleontologists are unable to extricate species-level variation from individual, sexual, re... more Human paleontologists are unable to extricate species-level variation from individual, sexual, regional, geographical, pathological, and skull bone variations despite sophisticated statistical methodology. Additionally, true variation within and between groups cannot be generated from a handful of regional and geographical specimens presently used in comparative studies. I therefore conclude that we cannot identify species in the human paleontological record. This conclusion is supported by the analysis and discussion (in this paper) of research conducted on, what I deem to be, three high-profile genus Homo fossil discoveries: Dmanisi hominins, Homo floresiensis, and Homo naledi. The data compiled in these comprehensive studies conclude that Dmanisi, floresiensis, and naledi share features with all Homo and Australopithecine taxa. Specifically, none of these three fossils clustered or aligned definitively with any Homo specimens. Consequently, it may now be prudent for us to use numbers or look for gross similarities and differences in hominin fossils to classify them. As such, identifying fossils at the genus level, which was proposed recently, might be a solution worth considering. Using genera will reduce the specificity needed in species identification, but it might be preferable to the chaos we have now in species-level identification. This paper is published in two parts.
Human paleontologists are unable to extricate species-level variation from individual, sexual, re... more Human paleontologists are unable to extricate species-level variation from individual, sexual, regional, geographical, pathological, and skull bone variations despite sophisticated statistical methodology. Additionally, true variation within and between groups cannot be generated from a handful of regional and geographical specimens presently used in comparative studies. I therefore conclude that we cannot identify species in the human paleontological record. This conclusion is supported by the analysis and discussion (in this paper) of research conducted on, what I deem to be, three high-profile genus Homo fossil discoveries: Dmanisi hominins, Homo floresiensis, and Homo naledi. The data compiled in these comprehensive studies conclude that Dmanisi, floresiensis, and naledi share features with all Homo and Australopithecine taxa. Specifically, none of these three fossils clustered or aligned definitively with any Homo specimens. Consequently, it may now be prudent for us to use numbers or look for gross similarities and differences in hominin fossils to classify them. As such, identifying fossils at the genus level, which was proposed recently, might be a solution worth considering. Using genera will reduce the specificity needed in species identification, but it might be preferable to the chaos we have now in species-level identification. This paper is published in two parts.
Human paleontologists are unable to extricate species-level variation from individual, sexual, ge... more Human paleontologists are unable to extricate species-level variation from individual, sexual, geographical, pathological, and skull bone variations despite sophisticated statistical methodology. Additionally, true variation within and between groups cannot be generated from a handful of regional and geographical specimens presently used in comparative studies. I therefore conclude that we cannot identify species in the human paleontological record. This conclusion is supported by the analysis and discussion (in this paper) of research conducted on, what I deem to be, three high-profile genus Homo fossil discoveries: Dmanisi hominins, Homo floresiensis, and Homo naledi. The data compiled in these comprehensive studies conclude that Dmanisi, floresiensis, and naledi share features with all Homo and Australopithecine taxa. Specifically, none of these three fossils clustered or aligned definitively with any Homo specimens. Consequently, it may now be prudent for us to use numbers or look for gross similarities and differences in hominin fossils to classify them. As such, identifying fossils at the genus level, which was proposed recently, might be a solution worth considering. Using genera will reduce the specificity needed in species identification, but it might be preferable to the chaos we have now in species-level identification. This paper is published in two parts.
... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and ... more ... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and the staff in the human paleontology division at the Natural History Museum, London, for all their efforts to accommodate me. Finally, I would ...
Homo-journal of Comparative Human Biology, Jul 1, 2009
The species problem is one of the most complex and enduring problems plaguing evolutionary biolog... more The species problem is one of the most complex and enduring problems plaguing evolutionary biology in general and human paleontology in particular. In the past 50 years, conceptions of species have diverged and speciated analogous to the present, largely accepted view of the hominin phylogeny. Conventional wisdom supports a ''bushy'' hominin phylogeny. However, chaos reigns because there is no agreed-upon methodology used to delimit species taxa in paleontology. This dispute is complicated by the ever-present intraspecific and interspecific morphological variation, which is itself exacerbated by other types of variation, including behavioral, ecological, geographical and temporal. When two or more of these forms of variation are used to delimit ''new'' extant or fossil species, any decision arrived at might be construed as arbitrary. This paper proposes that temporary cessation in assigning new names should be considered based on several critical problems: (1) the explosion of conceptions of a ''species'' arising from disagreements regarding species definitions, (2) differing interpretations of population variation, which lead to difficulty in interpreting hybridization in nature, leading in turn to the underestimation or overestimation of species, (3) the problem of modes of speciation being confounded with criteria used to distinguish among species, e.g., punctuated equilibrium posits high-speciation rates, and (4) the most common of all human traits, vanity.
In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analys... more In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analyses, are accepted as anatomically modern or given the lofty title of Proto-Cro-Magnons. However, their modernity has been questioned in the literature. In this research, 41 dimensions were measured on the crania and 21 dimensions were measured on the femora, tibiae, and innominates of Qafzeh, Skhul, Cro-Magnons, Neanderthals, and other archaic, early, and recent modern samples from Africa, Western Asia, Europe, and East Asia (total crania, N = 400 and total postcrania, N = 1191), to test the null hypothesis that the Qafzeh and Skhul hominids are 'Proto-Cro-Magnons.' Three alternate hypotheses were also tested: (1) the Qafzeh and Skhul hominids have morphometric affinities to one, some, or none of the regional sample groups in this research; (2) the Qafzeh and Skhul hominids are not the same sample; and (3) the Qafzeh and Skhul hominids have morphometric affinities to more archaic sample groups in this research. Canonical variate analysis based on log size/shape and shape D2 for male and female crania show quite clearly that the Qafzeh and Skhul hominids are distant from the Cro-Magnons but closer to African and Levantine sample groups. For females, analysis of the craniofacial variables show that Qafzeh 9 has strong morphometric similarities to the African, Mumba 2. For males, analysis of craniofacial variables show that Qafzeh 6, Skhul 4, and Skhul 5 have respectable morphometric similarities to several archaic moderns but much stronger morphometric similarities, in terms of facial variables, to the North African, Jebel Irhoud 1. Hierarchical cluster analysis presented similar results. Analysis of the male and female postcrania samples show that Qafzeh and Skhul are morphometrically distant from all modern sample groups. Based on the data in this research, the hypothesis that states that the Qafzeh and Skhul hominids are Proto-Cro-Magnons is rejected. Instead, the data support the alternative hypotheses that the Qafzeh and Skhul have strong morphometric affinities to archaic and early modern Africans and Levantines and that postcranially, they are morphometrically distant from all sample groups. Together, Qafzeh and Skhul show strong evidence of mosaic evolution.Ph.D.Biological SciencesBiostatisticsMorphologyPhysical anthropologySocial SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132228/2/9959845.pd
On November 16, 2012, two people searching for cans and bottles in a wooded area off Alden Mounta... more On November 16, 2012, two people searching for cans and bottles in a wooded area off Alden Mountain Road in Newport Township, Luzerne County,
In agriculture, animals and plants are engineered to produce pharmaceuticals, and crops are modif... more In agriculture, animals and plants are engineered to produce pharmaceuticals, and crops are modified to be nutritious, tolerant of herbicides and the natural environment, and resistant to disease. While these goals may seem practical, is it wise to modify plant systems without a clear idea of the long-term effects of genetic engineering in animals and humans? [1].
In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analys... more In the arguments on modern human origins, the Qafzeh and Skhul hominids, based on skeletal analyses, are accepted as anatomically modern or given the lofty title of Proto-Cro-Magnons. However, their modernity has been questioned in the literature. In this research, 41 dimensions were measured on the crania and 21 dimensions were measured on the femora, tibiae, and innominates of Qafzeh, Skhul, Cro-Magnons, Neanderthals, and other archaic, early, and recent modern samples from Africa, Western Asia, Europe, and East Asia (total crania, N = 400 and total postcrania, N = 1191), to test the null hypothesis that the Qafzeh and Skhul hominids are 'Proto-Cro-Magnons.' Three alternate hypotheses were also tested: (1) the Qafzeh and Skhul hominids have morphometric affinities to one, some, or none of the regional sample groups in this research; (2) the Qafzeh and Skhul hominids are not the same sample; and (3) the Qafzeh and Skhul hominids have morphometric affinities to more archaic sample groups in this research. Canonical variate analysis based on log size/shape and shape D2 for male and female crania show quite clearly that the Qafzeh and Skhul hominids are distant from the Cro-Magnons but closer to African and Levantine sample groups. For females, analysis of the craniofacial variables show that Qafzeh 9 has strong morphometric similarities to the African, Mumba 2. For males, analysis of craniofacial variables show that Qafzeh 6, Skhul 4, and Skhul 5 have respectable morphometric similarities to several archaic moderns but much stronger morphometric similarities, in terms of facial variables, to the North African, Jebel Irhoud 1. Hierarchical cluster analysis presented similar results. Analysis of the male and female postcrania samples show that Qafzeh and Skhul are morphometrically distant from all modern sample groups. Based on the data in this research, the hypothesis that states that the Qafzeh and Skhul hominids are Proto-Cro-Magnons is rejected. Instead, the data support the alternative hypotheses that the Qafzeh and Skhul have strong morphometric affinities to archaic and early modern Africans and Levantines and that postcranially, they are morphometrically distant from all sample groups. Together, Qafzeh and Skhul show strong evidence of mosaic evolution.Ph.D.Biological SciencesBiostatisticsMorphologyPhysical anthropologySocial SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132228/2/9959845.pd
American journal of human biology : the official journal of the Human Biology Council, Jan 10, 2017
We explore variations in body and limb proportions of the Jomon hunter-gatherers (14,000-2500 BP)... more We explore variations in body and limb proportions of the Jomon hunter-gatherers (14,000-2500 BP), the Yayoi agriculturalists (2500-1700 BP) of Japan, and the Kumejima Islanders of the Ryukyus (1600-1800 AD) with 11 geographically diverse skeletal postcranial samples from Africa, Europe, Asia, Australia, and North America using brachial-crural indices, femur head-breadth-to-femur length ratio, femur head-breadth-to-lower-limb-length ratio, and body mass as indicators of phenotypic climatic adaptation. Specifically, we test the hypothesis that variation in limb proportions seen in Jomon, Yayoi, and Kumejima is a complex interaction of genetic adaptation; development and allometric constraints; selection, gene flow and genetic drift with changing cultural factors (i.e., nutrition) and climate. The skeletal data (1127 individuals) were subjected to principle components analysis, Manly's permutation multiple regression tests, and Relethford-Blangero analysis. The results of Manly...
... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and ... more ... their fossil materials. I would like to thank Dr. Robert Kruszynski, Dr. Chris Stringer, and the staff in the human paleontology division at the Natural History Museum, London, for all their efforts to accommodate me. Finally, I would ...
Proceedings of the National Academy of Sciences, 2005
Many human craniofacial dimensions are largely of neutral adaptive significance, and an analysis ... more Many human craniofacial dimensions are largely of neutral adaptive significance, and an analysis of their variation can serve as an indication of the extent to which any given population is genetically related to or differs from any other. When 24 craniofacial measurements of a series of human populations are used to generate neighbor-joining dendrograms, it is no surprise that all modern European groups, ranging all of the way from Scandinavia to eastern Europe and throughout the Mediterranean to the Middle East, show that they are closely related to each other. The surprise is that the Neolithic peoples of Europe and their Bronze Age successors are not closely related to the modern inhabitants, although the prehistoric/modern ties are somewhat more apparent in southern Europe. It is a further surprise that the Epipalaeolithic Natufian of Israel from whom the Neolithic realm was assumed to arise has a clear link to Sub-Saharan Africa. Basques and Canary Islanders are clearly associ...
Human paleontologists are unable to extricate species-level variation from individual, sexual, re... more Human paleontologists are unable to extricate species-level variation from individual, sexual, regional, geographical, pathological, and skull bone variations despite sophisticated statistical methodology. Additionally, true variation within and between groups cannot be generated from a handful of regional and geographical specimens presently used in comparative studies. I therefore conclude that we cannot identify species in the human paleontological record. This conclusion is supported by the analysis and discussion (in this paper) of research conducted on, what I deem to be, three high-profile genus Homo fossil discoveries: Dmanisi hominins, Homo floresiensis, and Homo naledi. The data compiled in these comprehensive studies conclude that Dmanisi, floresiensis, and naledi share features with all Homo and Australopithecine taxa. Specifically, none of these three fossils clustered or aligned definitively with any Homo specimens. Consequently, it may now be prudent for us to use numbers or look for gross similarities and differences in hominin fossils to classify them. As such, identifying fossils at the genus level, which was proposed recently, might be a solution worth considering. Using genera will reduce the specificity needed in species identification, but it might be preferable to the chaos we have now in species-level identification. This paper is published in two parts.
Human paleontologists are unable to extricate species-level variation from individual, sexual, re... more Human paleontologists are unable to extricate species-level variation from individual, sexual, regional, geographical, pathological, and skull bone variations despite sophisticated statistical methodology. Additionally, true variation within and between groups cannot be generated from a handful of regional and geographical specimens presently used in comparative studies. I therefore conclude that we cannot identify species in the human paleontological record. This conclusion is supported by the analysis and discussion (in this paper) of research conducted on, what I deem to be, three high-profile genus Homo fossil discoveries: Dmanisi hominins, Homo floresiensis, and Homo naledi. The data compiled in these comprehensive studies conclude that Dmanisi, floresiensis, and naledi share features with all Homo and Australopithecine taxa. Specifically, none of these three fossils clustered or aligned definitively with any Homo specimens. Consequently, it may now be prudent for us to use numbers or look for gross similarities and differences in hominin fossils to classify them. As such, identifying fossils at the genus level, which was proposed recently, might be a solution worth considering. Using genera will reduce the specificity needed in species identification, but it might be preferable to the chaos we have now in species-level identification. This paper is published in two parts.
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