Here we present extended parts of the very interesting paper titled “Old World sources of the first New World human inhabitants: a comparative craniofacial view“, by C. Loring Brace et al.
Abstract Human craniofacial data were used to assess the similarities and differences between recent and prehistoric Old World samples, and between these samples and a similar representation of samples from the New World. The data were analyzed by the neighbor-joining clustering procedure, assisted by bootstrapping and by canonical discriminant analysis score plots. The first entrants to the Western Hemisphere of maybe 15,000 years ago gave rise to the continuing native inhabitants south of the U.S.-Canadian border. These show no close association with any known mainland Asian population. Instead they show ties to the Ainu of Hokkaido and their Jomon predecessors in prehistoric Japan and to the Polynesians of remote Oceania. All of these also have ties to the Pleistocene and recent inhabitants of Europe and may represent an extension from a Late Pleistocene continuum of people across the northern fringe of the Old World. With roots in both the northwest and the northeast, these people can be described as Eurasian. The route of entry to the New World was at the northwestern edge. In contrast, the Inuit (Eskimo), the Aleut, and the Na-Dene speakers who had penetrated as far as the American Southwest within the last 1,000 years show more similarities to the mainland populations of East Asia. Although both the earlier and later arrivals in the New World show a mixture of traits characteristic of the northern edge of Old World occupation and the Chinese core of mainland Asia, the proportion of the latter is greater for the more recent entrants.
Introduction Genetic and archaeological evidence supports a northeast Asian source for the first human inhabitants of the Western Hemisphere. Some interpretations have suggested that the distribution of linguistically identifiable groups in the New World may have been the result of separate prehistoric population movements into the Western Hemisphere.
From the sparse archaeological evidence and complementary molecular genetic data from living populations, an initial date of ca. 15,000 years can be postulated. Questions concerning the initial human settlement of the New World have involved such matters as the initial date of entry, route of access, whether there was a single or several dissimilar waves of people, and how these are genetically related both to living American Indian groups as well as to Asian and Pacific populations and possibly to other Old World peoples.
Morphometric Comparisons Recently these questions have been investigated by comparing patterns of the geographical distribution of human genetic and morphological features. Metric variables record inherited differences in cranial and facial form by documenting minor variations in the configuration of suture placement, length, and other details in the construction of the cranial vault and face. The various configurations of craniofacial form cluster regionally and are not distributed in clinal fashion related to the intensity of different selective force gradients. Furthermore, once established, configurations of facial form appear to remain relatively stable over considerable spans of time. Consequently, although details of facial form are distributed as regional groupings that may be viewed in the context of implied levels of biological relationship, these considerations must be made at a level well below that of the species. The human genotypic web is a subspecific, and therefore genetically open, system. None of the earlier human groups sampled in our data set, if they were all alive at the same time, would have been reproductively isolated in a fashion analogous to that of different species in a cladistic scheme. Because of this fact, the metrically indicated relationships depicted here, although of heuristic value in the examination of similarities and differences between groups of people across regions and through time, do not constitute a taxonomy in the strict sense of the term.
Here we integrate the results of the analysis of craniometric data showing the similarities and differences between prehistoric and recent samples representing the major regions of the Old World, the Pacific, and the New World. Our analysis is based on a set of 21 craniofacial measurements made of collections of human crania in the samples tested.
Results The resemblances and distinctions of samples representing the main geographic regions of the Old World are depicted in the neighbor-joining dendrogram displayed in Fig. 1. Also represented is the placement of the samples in relation to each other as determined by the first two discriminant functions. A composite of European Upper Paleolithic specimens from Czechoslovakia to France between 20 and 30 kya and a sampling of four European Neanderthals (from Gibraltar, France, and Italy) of ≈50 kya are also included.
Prehistoric and Recent Components of the Old World The Neanderthal twig of the dendrogram (Fig. 1A) is separated from the others by a greater distance than that discernible between any other possible pair. On the other hand, no matter what samples are used, it always links to the European twig before any other. This link is confirmed by the plot based on the first two canonical discriminant function scores (Fig. 1B). Only when a third discriminant function (accounting for 9.6% of total variance) is used (or, alternatively, a third principal component) do Neanderthals separate noticeably from recent Europeans. The separation of the northeast Africans as well as the European and South Asian samples from sub-Saharan Africa is compatible with the picture of genetic attenuation when the core of the African continent is compared with its northeastern edge and to extra-African peoples. The tie between Africa and Australo-Melanesia also has parallels at the molecular genetic level, where an African degree of haplotype and microsatellite diversity has echoes in the southern part of South Asia and over into Melanesia and Australia. One explanation is that this haplotype dates back to the initial human spread from Africa across the tropics of the Old World. The morphological and genetic distinctions of populations at the northwestern and northeastern edges of the Old World would then be the result of the subsequent northward spread of peripheral extensions from the continuous tropical corpus of the Old World’s main Paleolithic population concentration. Neither the genetic nor the morphological picture can give us any definitive estimate of the timing of that initial occupation of the tropics or the subsequent northward extensions.
The archaeological evidence shows that the Upper Paleolithic in Siberia arose by transformation from the preceding Mousterian in situ just under 40,000 years ago. Some have argued that the change in selective force pressure that accompanied the use of fire in processing food led to the reductions of tooth and jaw robustness that converted European Neanderthal into the early “modern” facial form at the northwest end of human habitation. In parallel fashion, the similar change in life ways shown by the archaeological sequence at the northeast end of that continuum should have led to the transformation of a similar Neanderthal morphology into a related “modern” form for the same reasons.
Prehistoric and Recent Components of East Asia Compared with the Rest of the Old World A brief test of such expectations is shown by the placement of the Late Pleistocene samples at both the western and the eastern ends of the Old World when they are compared with the regional representatives used in Fig. 1. To give a fuller representation of the living human form at the eastern edge of the Old World, Mongols from north central East Asia, Southeast Asians, and Ainus off the northeast edge of the continent were added to produce the pattern of resemblances and differences shown in Fig. 2. The Late Pleistocene sample from eastern Asia was made up of one individual from just under 30,000 years ago at the Upper Cave at Zhoukoudian just west of Beijing, China, and two individuals of just under 20,000 years ago at Minatogawa, Okinawa. The sample is very small and consists of males only, so the groups used to construct Fig. 2 were restricted to males from each of the populations represented. The added Mongol and Southeast Asian samples cluster with the Chinese samples used in Fig. 1, but the East Asian Pleistocene and the Ainu samples cluster with the European Upper Paleolithic and latterly with modern Europe itself before showing any linkage with the rest of the world.
Comparison of Late Pleistocene and Recent Components of East Asia and the Northwestern Part of the Old World Because the configurations represented in Africa, South Asia, and Australia/Melanesia are never linked with European, Asian, Oceanic, or New World samples, they were removed from the analyses when Oceanic and Western Hemisphere groups were being compared with the Old World. Fig. 3 shows the linkages and distinctions made when northern samples from Europe, Mongolia, China, and the Ainu of Japan are compared with Southeast Asia, Polynesia, and prehistoric groups in both Europe (Upper Paleolithic) and Japan (Jomon). The prehistoric Jomon and the Ainu of Japan are actually closer to the prehistoric and living European groups than to the core populations of continental Asia. The Polynesians of Oceania are close to being in between the European and Asian ends of the spectrum. Along with the Ainu and the Jomon, they could be described as Eurasian.
Comparison of Relevant Old World and New World Samples When samples representing the original inhabitants of the Western Hemisphere plus a Mongolian Bronze Age sample are added to the roster used to construct Fig. 3, we get the picture displayed in Fig. 4. Sandwiched between Europe and the European Upper Paleolithic is the Bronze Age Mongolian sample and a group ranging along the U.S.–Canadian border from Montana/Alberta (Blackfoot) to northern Michigan (the Juntunen site) and Ontario (the Ossossone site). Next to link with this cluster is a group made up of samples ranging from the American Southwest down through Mexico and South America. Then Jomon, Ainu, and Polynesian samples are displayed as further steps away from that northern Old World/New World cluster, although they remain closer to it than to the mainland Asian cluster of China, Mongolia, and Southeast Asia. The final two groups in Fig. 4, Athabaskans from the Yukon drainage of Alaska and a combined Aleut–Inuit sample across the northern edge of the New World, tie more closely to the mainland Asian cluster than they do to any of the other samples tested.
Discussion The fact that Late Pleistocene populations in northwest Europe and northeast Asia show morphological similarities suggests that there may have been actual genetic ties at one time. Those morphological similarities can still be shown between Europe and the descendants of the aboriginal population of the Japanese archipelago, i.e., the Ainu. This similarity provides some basis for the long-time claim that the Ainu represent an “Indo-European,” “Aryan,” or “Caucasoid” “type” or “race”, however unfortunate those designations and their implications may be.
That there is no evidence that the Late Pleistocene occupants of the longer-inhabited western end of that human extent migrated eastward* suggests that the genetic link may stem from a late Middle Pleistocene population spread across the northern edge of the Old World. Separate reductions of a common archaic level of robustness in the west and the east may account for the similarities in form of the living representatives at both ends of that range. When New World samples are added, those along the U.S.–Canadian border also tie in with that configuration, as does the Mongolian Bronze Age sample. An independent sign of that possible ancient continuity can be seen in the distribution of the X lineage of mitochondrial DNA that is present in low frequencies in Europe and across North America to the descendants of the pre-Columbian inhabitants of the Great Lakes area. The distribution of Y chromosome haplotypes is also compatible.
Fig. 4 supports the view that populations at the core of mainland East Asia (represented here by Mongolia, China, and Southeast Asia) only made partial contributions to the initial populating of the Western Hemisphere. It also suggests that the postagricultural expansion of that mainland East Asian population had an increasing impact on people at the northern and eastern edges of the continent as well as toward the south and out into the Pacific. The prehistoric Jomon of Japan, along with the living Ainu, still clearly resemble that northern stratum, although the latter are a bit closer to linking up with the mainland East Asian core. The same thing is true for the Polynesian samples, with the tie to the mainland Asian core being just slightly stronger than was true for the Ainu. The Inuits and the Na-Dene-speaking Athabaskans (the most recent groups to have left northeast Asia for the New World) show even more resemblance to the Chinese-related populations of mainland Asia.
*NovoScriptorium: Interestingly, there are descriptions of various ‘expeditions’ towards the East (and/or the West) in ancient Greek Mythology. Of course, this doesn’t constitute ‘evidence’, but we really wonder about the reasons references like these are totally ignored. From the ancient Worlds there are relatively few written documents. If we really care to learn about Humanity’s History, in no way should we ignore the Traditions, Oral or Written, of the various peoples.
Research-Selection for NovoScriptorium: Maximus E. Niles
Comments for NovoScriptorium: Isidoros Aggelos