Craniofacial plasticity in ancient Peru

Anthropologischer Anzeiger doi:10.1127/anthranz/2015/0458

Craniofacial plasticity in ancient Peru

Jessica H. Stone; Kristen Chew; Ann H. Ross; John W. Verano

Numerous studies have utilized craniometric data to explore the roles of genetic diversity and environment in human cranial shape variation. Peru is a particularly interesting region to examine cranial variation due to the wide variety of high and low altitude ecological zones, which in combination with rugged terrain have created isolated populations with vastly different physiological adaptations. This study examines seven samples from throughout Peru in an effort to understand the contributions of environmental adaptation and genetic relatedness to craniofacial variation at a regional scale. Morphological variation was investigated using a canonical discriminant analysis and Mahalanobis D2 analysis. Results indicate that all groups are significantly different from one another with the closest relationship between Yauyos and Jahuay, two sites that are located geographically close in central Peru but in very different ecozones. The relationship between latitude/longitude and face shape was also examined with a spatial autocorrelation analysis (Moran’s I) using ArcMap and show that there is significant spatial patterning for facial measures and geographic location suggesting that there is an association between biological variation and geographic location.

Link

Craniofacial morphology of Greeks through 4,000 years

Anthropol Anz. 2014;71(3):237-57.

Craniofacial morphology in ancient and modern Greeks through 4,000 years.

Papagrigorakis MJ, Kousoulis AA, Synodinos PN. Abstract

BACKGROUND:

Multiple 20th century studies have speculated on the anthropological similarities of the modern inhabitants of Greece with their ancient predecessors. The present investigation attempts to add to this knowledge by comparing the craniofacial configuration of 141 ancient (dating around 2,000-500 BC) and 240 modern Greek skulls (the largest material among relevant national studies).

METHOD:

Skulls were grouped in age at death, sex, era and geographical categories; lateral cephalograms were taken and 53 variables were measured and correlated statistically. The craniofacial measurements and measurements of the basic quadrilateral and cranial polygon were compared in various groups using basic statistical methods, one-way ANOVA and assessment of the correlation matrices.

OBSERVATIONS:

Most of the measurements for both sexes combined followed an akin pattern in ancient and modern Greek skulls. Moreover, sketching and comparing the outline of the skull and upper face, we observed a clock-wise movement. The present study confirms that the morphological pattern of Greek skulls, as it changed during thousands of years, kept some characteristics unchanged, with others undergoing logical modifications.

CONCLUSION:

The analysis of our results allows us to believe that the influence upon the craniofacial complex of the various known factors, including genetic or environmental alterations, is apt to alter its form to adapt to new conditions. Even though 4,000 years seems too narrow a span to provoke evolutionary insights using conventional geometric morphometrics, the full presentation of our results makes up a useful atlas of solid data. Interpreted with caution, the craniofacial morphology in modern and ancient Greeks indicates elements of ethnic group continuation within the unavoidable multicultural mixtures.

Link

Armed conflict in the Sahara, ~13 thousand years ago

An interesting story from the Independent:

Scientists are investigating what may be the oldest identified race war 13,000 years after it raged on the fringes of the Sahara. French scientists working in collaboration with the British Museum have been examining dozens of skeletons, a majority of whom appear to have been killed by archers using flint-tipped arrows.

...

Parallel research over recent years has also been shedding new light as to who, in ethnic and racial terms, these victims were.

Work carried out at Liverpool John Moores University, the University of Alaska and New Orleans’ Tulane University indicates that they were part of the general sub-Saharan originating population – the ancestors of modern Black Africans.

The identity of their killers is however less easy to determine. But it is conceivable that they were people from a totally different racial and ethnic group – part of a North African/ Levantine/European people who lived around much of the Mediterranean Basin.

The two groups – although both part of our species, Homo sapiens – would have looked quite different from each other and were also almost certainly different culturally and linguistically. The sub-Saharan originating group had long limbs, relatively short torsos and projecting upper and lower jaws along with rounded foreheads and broad noses, while the North African/Levantine/European originating group had shorter limbs, longer torsos and flatter faces. Both groups were very muscular and strongly built.

Craniometric discontinuity at the Last Glacial Maximum in Europe

The paper includes a craniometric dataset on 10 variables in the supplementary material.

Nature Communications 5, Article number: 4094 doi:10.1038/ncomms5094

Craniometric analysis of European Upper Palaeolithic and Mesolithic samples supports discontinuity at the Last Glacial Maximum

Ciaraán Brewster et al.

The Last Glacial Maximum (LGM) represents the most significant climatic event since the emergence of anatomically modern humans (AMH). In Europe, the LGM may have played a role in changing morphological features as a result of adaptive and stochastic processes. We use craniometric data to examine morphological diversity in pre- and post-LGM specimens. Craniometric variation is assessed across four periods—pre-LGM, late glacial, Early Holocene and Middle Holocene—using a large, well-dated, data set. Our results show significant differences across the four periods, using a MANOVA on size-adjusted cranial measurements. A discriminant function analysis shows separation between pre-LGM and later groups. Analyses repeated on a subsample, controlled for time and location, yield similar results. The results are largely influenced by facial measurements and are most consistent with neutral demographic processes. These findings suggest that the LGM had a major impact on AMH populations in Europe prior to the Neolithic.

Link

Analysis of Maikop crania (Kazarnitsky 2010)

From the paper, first a survey of other studies:

The Maikop cranium from Mandzhikiny I in Kalmykia was measured by A.A. Khokhlov. In his view, it resembles the previously published Maikop and Novosvobodnaya specimens. Khokhlov pointed to certain features common to the Maikop and Novosvobodnaya people and opposing them to the Pit Grave people. He questioned the resemblance between the Maikop crania from Evdyk I and those from Syezzheye and Zadono-Avilovsky; and he believed the former to resemble crania from the Caucasus, the Near East, and Southwestern Central Asia, being closest to those from Samtavro, Georgia, and Ginchi, Dagestan (Khokhlov, 2002).   

In a brief note, M.M Gerasimova, D.V. Pezhemsky, and L.T. Yablonsky (2002) described several Maikop crania from burial grounds on the Kalaus River in the Stavropol Region. The series is diverse and, judging by the results of multivariate analysis, is closest to the Chalcolithic group from Khvalynsk in the Samara Region.    

T.I. Alekseyeva (2004) measured a male skull from mound 13 burial 5 at Nezhinskaya near Kislovodsk (the plastic reconstruction of this individual’s appearance was made by L.T. Yablonsky), as well as two crania (male and female) from mound 70 burial 1 at Zamankul in Northern Ossetia. All these crania came from “Maikop– Novosvobodnaya” burials and were attributed to the Mediterranean variety of the Southern Caucasoid type which was distributed in Armenia, Georgia, Iran, and Mesopotamia during the Chalcolithic and Early Bronze Age. The heterogeneity of the Maikop group in Alexeyeva’s opinion may be due to individual variability, but also to admixture with the natives of the southeastern European steppes (Alekseyeva, 2004). 

Later, Gerasimova, Pezhemsky, and Yablonsky (2007) published a large article where crania from burial grounds on the Kalaus River were described in detail. They noted that the Maikop series is heterogeneous but on average it represented the Eastern Mediterranean trait combination. The latter is quite dissimilar to the Cromagnoid combination typical of certain Bronze Age groups of the Eastern European steppes. The idea that at least some Maikop people were descendants of immigrants from the Near East was deemed probable; however the role of the steppe admixture, possibly accounting for a somewhat greater robustness of Maikop crania compared to Mediterranean ones, was not excluded either.

And the author's own conclusions:

In sum, the results of the multivariate analysis suggest that Maikop people are distinct from all the contemporary and later Eastern European groups of the steppe and forest-steppe zones. This provides an additional argument in favor of the hypothesis that Maikop burials in Kalmykia attest not merely to the cultural impact of the Maikop community on the steppe tribes (Munchaev, 1994: 168); rather, they were left by a separate group which was unrelated to the local Pit Grave population by origin. The Southern Caucasoid trait combination revealed by the Maikop series is somewhat similar to that shown by the contemporaneous groups of the Northern Caucasus and southern Turkmenia. Clearly, this does not imply a direct connection with any of these regions.  

The Near Eastern parallels are no less suggestive (Bunak, 1947: 77). Thus, a small series from Al-Ubaid in southern Mesopotamia, dating from the 4th millennium BC, is characterized by dolichocrany (cranial index, 72.6), a high face, medium wide, high and sharply protruding nose, and wide palate (Keith, 1931: 239–241). Regrettably, the number of measurements is too small to warrant a reliable comparison with the Maikop series. However, the isolated position of the Maikop group in Eastern Europe, its vague resemblance to the Southern Caucasoids of the Caucasus and Southwestern Central Asia, and the Near Eastern cultural affinities of Maikop and Novosvobodnaya (Munchaev, 1994: 170) indirectly point to Near Eastern provenance.

It would certainly be interesting to obtain DNA from some of these specimens.

Related:

• The Maikop Singularity
• Origins of the Maykop phenomenon
• Uruk migrants in the Caucasus

Archaeology, Ethnology and Anthropology of Eurasia
Volume 38, Issue 1, March 2010, Pages 148–155

THE MAIKOP CRANIA REVISITED

Abstract Measurements of crania of people associated with the Early Bronze Age Maikop culture of the Northern Caucasus are analyzed. Data on Maikop males, new and previously published, were compared with those concerning chronologically and geographically related people using the canonical variate analysis. The Maikop series turned out to be isolated and no close parallels to it were found among the Bronze Age groups, either from the steppe and forest-steppe zones of Eastern Europe or from the Caucasus and Southwestern Central Asia. While certain parallels seem to point to the Near East, they are too few to warrant definite conclusions.

Link

Interesting commentary on the Morton/Gould affair

Interesting commentary by the author of a 1988 undergraduate thesis that revolved around re-measuring part of Morton's skulls and concluding (contra Gould) that Morton's measurements were accurate.

I haven't read it fully (it is in four parts), but here is the concluding paragraph from part 4:

In the final analysis, the Morton-Gould Affair, which has been popularized as a diagnostic example of the role of unconscious bias in science, is simply a case of two over-eager scholars jumping to conclusions based on a small amount of data. It is unfortunate that the discussion of Morton’s work has occupied so much energy over the past 30 years, when a more important issue is Gould’s historically inaccurate misrepresentation of Blumenbach’s work, which unlike Morton’s was a foundational element of modern physical anthropology and public policy regarding racial variation that still impacts us today. A proper representation of Blumenbach’s theories and an accurate translation of his major Latin publications into modern English and German are long overdue and would be of great benefit to science and society at large.

Should be interesting reading for anyone fascinated by the history of ideas.

Polynesian mtDNA in extinct Amerindians from Brazil

From the paper:

In 1808 the Portuguese Crown declared “Just War” (Bellumiustum) against all Indian tribes that did not accept European laws (23). The fierce Botocudo were targeted in such wars and, in consequence, became virtually extinct by the end of the 19th century (24). Their importance for the history of the peopling of the Americas was revealed by studies reporting that the Botocudo had cranial features that consistently were described as intermediate between the polar Paleoamerican and Mongoloid morphologies (25, 26). Multivariate analyses of the cranial measures of different Amerindian and Paleoamerican groups from Brazil indeed concluded that the Botocudo Indians presented sufficient similarities with the Lagoa Santa Paleoamericans to be considered candidates to be their possible descendants (27).

Possible explanations:

The first scenario, prehistoric, is related to the possibility of genetic continuity between the Paleoamericans from Lagoa Santa and Botocudo Indians (26, 27, 37), which indeed originally had motivated this study. 

... 

Another imaginable pre-Columbian scenario involves opportunities for more recent direct contact between Polynesia and South America before the European arrival. Such possibility of a direct movement from Oceania across the Pacific Ocean to the Americas was raised by Cann (43) on a discussion of the origin of the Amerindian B haplogroup. This finding prompted Bonatto et al. (44) to evaluate the likelihood of a Polynesian-Amerindian contact having occurred and conclude against it, although they could rule out neither minor contact events nor nonmaternal genetic exchange. New evidence from human and nonhuman material has become available since then. For example, there were archeological findings of Polynesian chicken bones in the Arauco Peninsula, in Chile (45) and evidence has been found in Easter Island of pre-Columbian presence of sweet potato and bottle gourd, both typical of South America (46, 47). Independent of the plausibility or implausibility of the pre-Columbian arrival of Polynesians to the South American Pacific coast, there still would remain the need to explain how these migrants crossed the Andes and ended up in Minas Gerais, Brazil. We feel that such a scenario is too unlikely to be seriously entertained. 

... 

The last scenario that we wish to assess is the possible arrival of Polynesian haplogroups to Brazil in modern times through the African slave trade from Madagascar, where 20% of the mtDNA lineages belong to the B4a1a1a haplogroup (29).

It may be of relevance that both Tianyuan (~40ka) and Boshan (~8ka) from China belong to mtDNA haplogroup B and that B belongs to the R (and N) clade of the mtDNA phylogeny, i.e., a different branch of Out-of-Africa than C (which belongs to M). I wager that interesting things were taking place in East Eurasia and the New World until fairly recent times, and hopefully ancient DNA will help us complete the picture.

PNAS doi: 10.1073/pnas.1217905110

Identification of Polynesian mtDNA haplogroups in remains of Botocudo Amerindians from Brazil

Vanessa Faria Gonçalves et al.

There is a consensus that modern humans arrived in the Americas 15,000–20,000 y ago during the Late Pleistocene, most probably from northeast Asia through Beringia. However, there is still debate about the time of entry and number of migratory waves, including apparent inconsistencies between genetic and morphological data on Paleoamericans. Here we report the identification of mitochondrial sequences belonging to haplogroups characteristic of Polynesians in DNA extracted from ancient skulls of the now extinct Botocudo Indians from Brazil. The identification of these two Polynesian haplogroups was confirmed in independent replications in Brazil and Denmark, ensuring reliability of the data. Parallel analysis of 12 other Botocudo individuals yielded only the well-known Amerindian mtDNA haplogroup C1. Potential scenarios to try to help understand these results are presented and discussed. The findings of this study may be relevant for the understanding of the pre-Columbian and/or post-Columbian peopling of the Americas.

Link

Bulging modern human foreheads

AJPA DOI: 10.1002/ajpa.22202

Geometric variation of the frontal squama in the genus homo: Frontal bulging and the origin of modern human morphology

Emiliano Bruner et al.

The majority of studies of frontal bone morphology in paleoanthropology have analyzed the frontal squama and the browridge as a single unit, mixing information from different functional elements. Taking into account that the bulging of the frontal bone is often described as a species-specific trait of Homo sapiens, in this article we analyze variation in the midsagittal profile of the genus Homo, focusing on the frontal squama alone, using landmark-based superimpositions and principal components analysis. Our results demonstrate that anatomically modern humans are definitely separated from extinct human taxa on the basis of frontal bulging. However, there is minor overlap among these groups, indicating that it is necessary to exercise caution when using this trait alone to make taxonomic inferences on individual specimens. Early modern humans do not show differences with recent modern humans, and “transitional” individuals such as Jebel Irhoud 1, Maba, and Florisbad, show modern-like frontal squama morphology. The bulging of the frontal squama in modern humans may represent a structural consequence of more general cranial changes, or it could be a response to changes in the morphology of the underlying prefrontal brain elements. A subtle difference between Neandertals and the Afro-European Middle Pleistocene Homo sample is associated with flattening at bregma in the former group, a result that merits further investigation.

Link

f3-statistics on craniometric data?

It occurred to me that the concept of f3-statistics, originally developed to detect admixture by exploiting allele frequency difference anti-correlations could very well be applied to craniometric data as well.

The basic idea is quite simple: suppose that for a metric trait, two populations A and B have mean value a and b and that a third population C is formed by mixture between A and B. Unlike allele frequencies where the admixed population's frequency will be between a and b immediately post-admixture, anthropometric traits may respond in unexpected ways to admixture (e.g., heterosis might cause first-generation offspring to exceed both their parents in height, rather than exhibit an intermediate value). I will leave the justification of the hypothesis that "mixed-origin offspring will possess intermediate metric traits" to the physical anthropologists, who may have gathered data on such things, and, for the present, I will take it for granted.

So, assuming that c, the mean trait in the mixed population, is between a and b, we can easily see that (c-a)(c-b) will be negative, and hence so will be the correlation coefficient (over many traits) between C-A and C-B, where by C-A I denote the k-long vector difference of mean trait values between populations C and A.

Going back to my analysis of Howells' dataset, I calculated population means for 57 traits over the NORMALIZED_DATA array of modern populations (in which sexual dimorphism has been removed and traits of different scale have been normalized in standard deviation units), and calculated 30*choose(29,2) correlations for each of 30 populations, expressed as a mixture of any pair of the remaining 29.

I list below, the top 20 anti-correlations, and highlight a few in bold (third population as mixture of first two):


BURIAT ANDAMAN PHILLIPI -0.54005191575771
EGYPT BURIAT NORSE -0.490018084440697
ANDAMAN ANYANG HAINAN -0.48323680182295
BURIAT ANDAMAN HAINAN -0.480939028739347
EGYPT BURIAT ZALAVAR -0.476445836100052
ANDAMAN ANYANG PHILLIPI -0.457902384166767
DOGON BURIAT PHILLIPI -0.416551851781419
BERG EASTER_I ZALAVAR -0.378996437433417
AUSTRALI BURIAT ARIKARA -0.375898166338775
BURIAT EASTER_I MOKAPU -0.37169703838378
ESKIMO ANDAMAN S_JAPAN -0.366611599944932
ESKIMO PERU N_JAPAN -0.354535077363928
TOLAI BURIAT ARIKARA -0.348110323746154
BERG EGYPT ZALAVAR -0.344843098962355
DOGON ESKIMO GUAM -0.344577928128792
TOLAI BURIAT GUAM -0.338804214799388
ESKIMO PHILLIPI GUAM -0.336537918547276
DOGON BURIAT HAINAN -0.332635954428392
TASMANIA BURIAT ARIKARA -0.331301837598433
ESKIMO PERU S_JAPAN -0.330302035072489

Some interesting ones:

• Philippines as Buriat+Andaman; this makes sense if Philippines is the result of admixture between an "East Asian" and a "Negrito" population
• Norse as Egypt+Buriat; the Howells "Egypt" sample is "Mediterranean" in the classical sense. Perhaps this involves the same "East Eurasian"-like signal of admixture detected by genetic methods? Similar signal also occurs for Zalavar (from Hungary)
• Hainan as Andaman+Anyang; south Chinese as Neolithic Chinese+"Negrito"-like old south Chinese?
• Arikara as Buriat+Australian; admixture between "Australoid" Paleo-Indians and "Mongoloid" ones? or between 1st wave Indians and later ones (sensu Reich et al. 2012)?
• Guam as Tolai+Buriat; admixture between "Papuan"-like and East Asian-like people in Polynesia?

As with "normal" f3-statistics, absence of a negative correlation does not reject admixture; this may be especially the case here, because phenotypes may be affected by strong natural selection during the post-admixture period.

And, there are some difficult-to-interpret cases (e.g., Philippines as Buriat+Dogon) which may point to limitations of the method; for example, the Dogon may act as a stand-in for the "equatorial"-like physique of the true "Andaman"-like mixing element. Presumably such limitations can be overcome by limiting the analysis to "selectively neutral" traits, rather than the whole suite of 57 Howells variables used here.

I certainly think that the idea ought to be investigated further: it might be redundant when genetic data are available, but may prove useful in the analysis of admixture when such data do not exist, e.g., in anthropological data of prehistoric specimens from hot climates where archaeogenetic evidence may never materialize. 

From Skulls and Scans (Monge & Aguirre @ Penn)

An interesting talk on the uses and abuses of science.

 

I find this excerpt particularly offensive to my open science sensibilities (29:40 ff):

We were able to, after 10 years, actually get it published in PLoS Biology, took us 10 years, yeah, we were rejected every single place that we ever sent the manuscript. I find that interesting too, and we even had editors say to us that they didn't want to say anything against Stephen J Gould. Isn't that interesting?

Interesting indeed. As I wrote in my review of the Lewis et al. (2011) paper on the Gould vs. Morton affair:

It is remarkable that 30 years after the Mismeasurement of Man Gould's errors are uncovered. Why did it take so long? While one could understand why the (totally unfounded but -on the surface- plausible) idea of measurement bias could have gone unnoticed until someone actually re-measured the skulls, but the statistical error that Gould committed was there for anyone to see.

We now know why it took at least 10 out of these 30 years: stuck in journal limbo.

3D laser scan of Stonehenge reveals axehead graffiti

Stonehenge up close: digital laser scan reveals secrets of the past

The first complete 3D laser scan of the stone circle has also revealed tool marks made 4,500 years ago, scores of little axehead graffiti added when the enormous slabs were already 1,000 years old, and damage and graffiti contributed by Georgian and Victorian visitors. 

...

Long after the monument was built, when Bronze Age burial mounds rich in grave goods began to be scattered across the plain around Stonehenge, and the archaeological evidence suggests those who could make or trade in metal goods had an almost shamanic status, people carved little images of daggers and axes, many now invisible to the naked eye, into the stones. Scores more have been revealed by the scan, including 71 new axe heads, bringing the total to 115 – doubling the number ever recorded in Britain.

"It is wonderful to have discovered so many more, but what is fascinating is that they are carved without regard to the importance or the siting of the stones – almost as if the people who carved them could no longer quite remember the significance of the monument and how it worked," Greaney said.

They probably could no longer remember, because they were Indo-European newcomers, and not the same people as the Megalithic folk who built Stonehenge.

A little history:

Craniologists of the time used a ratio based on length and width measurements, known as the cranial index, to divide skulls into two basic types: 'dolichocephalic', long and narrow in shape, and 'brachycephalic', broad and round in shape. Based on his observations at sites like Belas Knap, Thurnam established his famous axiom, 'long barrows, long skulls; round barrows, round skulls'. The long skulls were found in long barrows and never in association with metallic artefacts, while round skulls were found in round barrows sometimes with metalwork. 

... 

Thurnam's and Rolleston's theories gained considerable credibility in the late Victorian period and survived well into the earlier 20th century. Such racist theories failed to stand up, however, in the face of Gordon Childe's arguments for the definition of an archaeological culture based on shared social characteristics and material culture rather than race or biological type. In addition, the considerable moral repugnance felt towards Victorian anthropology and its role in the rise of fascist ideology in the 1930s caused the argument over long and round skulls to be sidelined and eventually dismissed. The identification of the Bronze Age incomers based on their material culture, including metalwork and Beaker pottery vessels, remained a more acceptable alternative.
In the 1990s, however, the archaeologist Neil Brodie took a fresh look at the craniological evidence and concluded that there was undeniably a difference between the shape of skulls from Neolithic long barrows and Bronze Age round barrows. A trend from long to round skull shape was clearly shown. 

The differences, he argued, could be caused by cultural practices, such as the binding of infants' heads, as well as by diet and a range of climatic or environmental factors. Looking at the totality of human history, he showed that head shape fluctuates in populations over long periods of time, and that extremes of head types occur in successive prehistoric populations as a matter of historical chance.

We don't have DNA evidence from British round barrows yet, but Beaker burials from Germany show the first R1b ever found, while Neolithic Western Europe shows a mix of I2a and G2a. Difference in material culture? check. Difference in physical anthropology? check. Difference in time of appearance? check. Difference in genetics? preliminary check.

So, it seems like a good bet that the people who carved axehead graffiti on Stonehenge were simply invaders who took over the site from the previous inhabitants, and, as is so often the case, used it for their own purposes.

Tam Pa Ling: modern humans in Southeast Asia at 63-46ka

I have become convinced that the roots of the Eurasian dispersal occurred at around 70 thousand years ago, from an earlier population of modern humans that had left Africa for the Levant and Arabia before 100 thousand years. So, the discovery of a new anatomically modern human from Southeast Asia that is directly dated to 63ka and can be no younger than 46ka is a welcome addition to the record.

The Tam Pa Ling skull would be of similar age to the Liujiang skull from China if the latter's 68ka age is accepted. So, now the case is much more secure for the presence of modern humans in the Far East in the interval between the 70ka Event, and the post-50ka symbolic revolution associated with the MP/UP transition. If we add to the equation the presence of an UP European-like skull at Qafzeh in Israel at ~100ka, and of the Nubian Complex in South Arabia at ~106ka,  it is becoming increasingly difficult to accept ideas about either a 60ka coastal migration, or a late Out-of-Africa migration associated with the Upper Paleolithic that somehow replaced the people who lived all over Eurasia.

From the press release:

"It's a particularly old modern human fossil and it's also a particularly old modern human for that region," said University of Illinois anthropologist Laura Shackelford, who led the study with anthropologist Fabrice Demeter, of the National Museum of Natural History in Paris. "There are other modern human fossils in China or in Island Southeast Asia that may be around the same age but they either are not well dated or they do not show definitively modern human features. This skull is very well dated and shows very conclusive modern human features," she said. 

No other artifacts have yet been found with the skull, suggesting that the cave was not a dwelling or burial site, Shackelford said. It is more likely that the person died outside and the body washed into the cave sometime later, she said. 

The find reveals that early modern human migrants did not simply follow the coast and go south to the islands of Southeast Asia and Australia, as some researchers have suggested, but that they also traveled north into very different types of terrain, Shackelford said.

UPDATE (Aug 27): Coverage in Hominid Hunting.

PNAS doi: 10.1073/pnas.1208104109

Anatomically modern human in Southeast Asia (Laos) by 46 ka

Fabrice Demeter et al.

Uncertainties surround the timing of modern human emergence and occupation in East and Southeast Asia. Although genetic and archeological data indicate a rapid migration out of Africa and into Southeast Asia by at least 60 ka, mainland Southeast Asia is notable for its absence of fossil evidence for early modern human occupation. Here we report on a modern human cranium from Tam Pa Ling, Laos, which was recovered from a secure stratigraphic context. Radiocarbon and luminescence dating of the surrounding sediments provide a minimum age of 51–46 ka, and direct U-dating of the bone indicates a maximum age of ~63 ka. The cranium has a derived modern human morphology in features of the frontal, occipital, maxillae, and dentition. It is also differentiated from western Eurasian archaic humans in aspects of its temporal, occipital, and dental morphology. In the context of an increasingly documented archaic–modern morphological mosaic among the earliest modern humans in western Eurasia, Tam Pa Ling establishes a definitively modern population in Southeast Asia at ~50 ka cal BP. As such, it provides the earliest skeletal evidence for fully modern humans in mainland Southeast Asia.

Link

Morphometric analysis of Zuttiyeh (Freidline et al. 2012)

The Zuttiyeh specimen from Israel (unknown date, but between 500-200ka) is extremely important, because it was found in a region of the world in which the earliest co-existence of modern humans and Neandertals is attested. As such, it may be part of a population that led to either (or both) of these species; the population divergence of the Homo sapiens and Homo neandertalensis lineages intersects the 500-200ka range of this specimen.

A recent paper in the Journal of Human Evolution studied Zuttiyeh using geometric morphometric techniques.

Zuttiyeh (Zt) was compared with a wide range of other specimens from various periods, ranging from Homo erectus to modern humans. The PCA analysis is shown on the left. It is clear that Zuttiyeh clusters with Neandertals in Eurasia (open triangles), as well as "transitional" Homo sapiens from Africa (open squares: Florisbad Fl, 290-230ka from South Africa, and Jebel Irhoud 1 I1, 160ka from Morocco).

On the left (filled triangles) are various specimens assigned to Homo heidelbergensis, the presumed common ancestor of modern humans and Neandertals. For more on this, see Chris Stringer's recent overview article. But, this is no simple ancestor species: rather, it encompasses skulls that are very old (Bodo Bd; Ethiopia ca. 600ka), and very young (Dali Dl; China ca. 200ka). Indeed, Zhoukoudian 12 (Zh12; >500ka China) classified as Homo erectus appears quite modern in comparison to many of the heidelbergensis skulls.

On the right (crosses) are the modern humans, including UP Europeans, as well as, intriguingly Liujiang (Ljg), a modern human from China that may be 119-139ka old according to the people who dated it, but at least 68ka old. If the latter date is accepted, this would be within the error bars of the major 70ka Event that may correspond to the earliest colonization of Eurasia. If the former, then Liujiang will join the Qafzeh 9 specimen as an extremely modern pre-100ka find from Asia.

The Mount Carmel specimens (Qafzeh 6 Q6 and Skhul 5 Sk5; Levant 135-100ka) appear intermediate between H. heidelbergensis/H. neanderthalensis and H. sapiens but can usefully be called H. sapiens, since there are modern humans who appear as "left-shifted" as they are.

Intriguingly, Shanidar 5 (Sh5; ca. 50ka) a Neandertal appears to be much closer to H. sapiens than to his Neandertal brethren (including contemporaneous Sh1). This seems to be in line with a recent analysis of shoulder blades in which Shanidar 3 was included, as was a contemporaneous Vindija Neandertal (= the source of the Neandertal genome). It may well appear that late Neandertals were not diverging away from a modern humans, but rather changing from the ancestral heidelbergensis state in the same way that modern humans are.

A neglected possibility is that the late Neandertals, around the time of the apparent modern human Big Bang experienced gene flow from modern humans. This scenario was rejected in the original publication of the Neandertal genome on the basis of the idea that modern human admixture in Neandertals would have been modern non-African-like, because, presumably it was effected by a wave of Proto-Eurasians leaving Africa. But, if the Big Bang of human expansion occurred in Asia, perhaps in Arabia as it dried up post-70ka, as I have suggested, then modern human admixture could have affected late Neandertals.

The discriminant function analysis is also interesting:

The groups were defined a priori according to the population grouping shown in Table 1. Zuttiyeh as well as all transitional (Jebel Irhoud 1 and Florisbad), early (Skhul 5, Qafzeh 6 and Luijiang) and Upper Paleolithic H. sapiens were treated as individuals with unknown group affinities to be classified by posterior probabilities.

 Florisbad appears to be quite distinct here, while Skhul5 and Qafzeh6 are clearly on their way to becoming modern; Zhoukoudian 101 joins this group (13-33ka), but is about 70-100 thousand years younger. Apparently the population of modern humans in Eurasia pre-100ka was widespread. Individuals of regular modern aspect appear post-70ka Event in both West and East Eurasia (Zh102 and Liujiang, assuming the latter is 68ka old). They probably appear in Africa as well probably in Africa as well.

Sadly, neither Hofmeyr, nor Omo I/II and Herto were included in this analysis. All of the above are often mentioned in connection to modern human origins. So is Kabwe (Broken Hill; Homo rhodesiensis) which is listed here as 700-400ka but may in fact be much younger. Jebel Irhoud 1 a "transitional" Homo sapiens from Morocco seems to have a long way to go to transition to a fully modern shape. Both Amud 1 (Am1; a big-brained late Neandertal from the Levant 50ka) and the aforementioned Shanidar 5 appear just as modern as Irhoud 1.

Can we make any sense of these various facts? I will list some observations:

• Zuttiyeh appears linked to Neandertal and transitional H. sapiens. It is unclear where to place it, except to say that it is an archaic-looking human who is in the process of evolving in the same direction that both Neandertals and modern humans did.
• There does not appear to be any good evidence in this data that H. heidelbergensis underwent a split that led to modern humans and Neandertals. On the contrary, often younger skulls appear more archaic than older ones, and skulls from the same period/region seem to occupy different positions in the archaic/modern range.
• Modern humans appear distinctive, with their closest pre-100ka relatives being the Mt. Carmel hominins from the Levant (Skhul and Qafzeh), as well as, intriguingly, late Near Eastern Neandertals (Amud and Shanidar)

Even during the last 50ky, there seems to have been elevated diversity in modern humans. Zhoukoudian 101 from this study appears to be one example of unusual morphology for so late a specimen; recent discoveries from China and Sub-Saharan Africa point to the same phenomenon.

I continue to think that within the Homo heidelbergensis lineage there was progress towards more modern forms throughout the old world. But, this progress did not replace the older forms; nor did it materialize as obviously divergent lineages. The last few hundred thousand years appear very much like a serious of experiments that lead in some vague way to something akin to us. There probably was a long, drawn-out road to us.

In Africa, the Near East, and Asia, there was a co-existence of quite divergent forms; even Europe, long-considered the exclusive abode of Neandertals, there apparently lived humans  that did not possess the derived Neandertal morphology.

The simple story of our origins is that our common ancestor H. heidelbergensis split into an African and Eurasian lineage that eventually evolved into H. sapiens and H. neanderthalensis, and finally the former replaced the latter, with perhaps a little admixture along the way.

It would appear that aspects of modernity appeared throughout the Old World during the last few hundred thousand years. Perhaps (as the multi-regionalists would have it), this was facilitated by gene flow between distant human groups; alternatively, H. heidelbergensis already had the seeds of his future evolution, and similar solutions were found for similar selective pressures independently.

For the time being, we must probably accept the fact that a great variety of human groups of the last 500,000 years at least have contributed to modern mankind. Only isolated groups like Homo floresiensis who disappeared before having the chance to affect us may have escaped the honor of being our ancestors. But, it also seems that much of our ancestry does come from a unique population emerging somewhere within that broader milieu. Where this population lived and why it became so successful is an open problem, but, until there is evidence to the contrary, I would say that my two deserts theory, as elaborated here, may be a reasonably candidate.

Journal of Human Evolution Volume 62, Issue 2, February 2012, Pages 225–241

A comprehensive morphometric analysis of the frontal and zygomatic bone of the Zuttiyeh fossil from Israel

S.E. Freidline et al.


The Zuttiyeh hominin craniofacial fossil was discovered in Israel in 1925. Radiometric dates and the archaeological context (Acheulo-Yabrudian) bracket the associated cave layers to between 200 and 500 ka (thousands of years ago), making it one of the earliest cranial fossils discovered in the Near East thus far. Its geographic position, at the corridor between Africa and Eurasia, in combination with its probable Middle Pleistocene date make it a crucial specimen for interpreting later human evolution. Since its discovery, qualitative descriptive and traditional morphometric methods have variously suggested affinities to Homo erectus (Zhoukoudian), Homo neanderthalensis (Tabun), and early Homo sapiens (Skhul and Qafzeh). To better determine the taxonomic affinities of the Zuttiyeh fossil, this study uses 3D semilandmark geometric morphometric techniques and multivariate statistical analyses to quantify the frontal and zygomatic region and compare it with other Middle to Late Pleistocene African and Eurasian hominins.

Our results show that the frontal and zygomatic morphology of Zuttiyeh is most similar to Shanidar 5, a Near East Neanderthal, Arago 21, a European Middle Pleistocene hominin, and Skhul 5, an early H. sapiens. The shape differences between archaic hominins (i.e., Homo heidelbergensis and H. neanderthalensis) in this anatomical region are very subtle.

We conclude that Zuttiyeh exhibits a generalized frontal and zygomatic morphology, possibly indicative of the population that gave rise to modern humans and Neanderthals. However, given that it most likely postdates the split between these two lineages, Zuttiyeh might also be an early representative of the Neanderthal lineage. Neanderthals largely retained this generalized overall morphology, whereas recent modern humans depart from this presumably ancestral morphology.


Link (pdf)

Anthropological Investigation of the S. Greece population’s composition in the Bronze Age

Here is a link to S. K. Manolis's 1991 dissertation which complements the previous one by G. Panagiaris, since it includes data from the Peloponnese and Crete. I might translate parts of it in the space below. The author seems to argue for an environmental cause of brachycephalization during the Bronze Age; personally I think that the more likely explanation is intrusion by mountain-folk from either the Pindos area or Anatolia, associated with metallurgy. In any case, I am hopeful that some of the Ancient Greek osteological material, some of which has been excavated many decades ago may still possess usable DNA that could be exploited in future studies that may overcome the limits of craniometry.

A physico-anthropological study of skeletal material from Neolithic age to Hellenistic times in Central Greece and surrounding region

I have located the text of George Panagiaris important 1993 doctoral thesis on Greek skeletal material. This may be one of the most comprehensive efforts to study the Ancient Greek population from a physical anthropological perspective (413 male and 354 female crania, using 65 biometric characters as well odontological traits).

Panagiaris' conclusions in English can be found in p.10 of the document. He confirms that the greater period of discontinuity in the material is observed during the Helladic period (=Bronze Age in Greek archaeology), where broad-headed incoming groups appear, side by side with the older Mediterranean population. He attributes this to the arrival of such people from the highlands Pindos range, although he sees the possibility of Anatolian influences as well, but has no comparative data. He cites the tendency for broader skulls in higher latitudes, although this general trend in H. sapiens probably does not explain the local trend within Caucasoids where the key difference is between mountaineers (where the Alpine, Dinaric, Armenoid, and Pamir-Ferghana types are well-represented) and lowland folk. Perhaps, if various ancient DNA projects manage to study some Greek material we may be able to ascertain the events that were taking place in Greece at that time.


Of course, the issue cannot be seen in isolation, because at this time we see an increase in brachycephalic types in Crete and Anatolia, the appearance of the intrusive brachycephalic Bell Beaker folk in Western Europe, and perhaps even the presence of the interfluvial type (Pamir-Ferghana type) in the eastern Saka. 

Personally, I see something important in these developments: why would broad-headed mountaineers make their appearance in the lowlands at this time in history? I am strongly leaning towards the idea that this has to do with metallurgical innovation during this time. According to Roberts et al. (2009), from which the figure on the left is taken:

Metallurgy in Eurasia originated in Southwest Asia due to the widespread adoption of, and experimentation in, pyrotechnology and the desire for new materials to serve as aesthetic visual displays of identity, whether of a social, cultural or ideological nature. This can be demonstrated through the early use of metal for jewellery and the use of ore-based pigments along with the continued use of stone, bone, and other materials for most tools. The subsequent appearance of metals throughout Eurasia is due to the acquisition of metal objects by individuals and communities re-inventing traditions of adornment, even in regions hundreds of kilometres from the nearest sources of native metals or ores. The movement of communities possessing metallurgical expertise to new ore sources and into supportive societies led to the gradual transmission of metallurgy across the Eurasian landmass. By the second millennium BC, metallurgy had spread across Eurasia, becoming firmly rooted in virtually all inhabitable areas (Sherratt 2006). The ability to smelt different ores, create different metals or increase metal production did not occur in a linear evolutionary fashion throughout Eurasia, but rather appeared sporadically over a vast area – a result of regional innovations and societal desires and demands. 

There is no evidence to suggest that metallurgy was independently invented in any part of Eurasia beyond Southwest Asia. The process of metallurgical transmission and innovation created a mosaic of (frequently diverse) metallurgical traditions distinguished by form, composition and production techniques. It is within this context that innovations such as the earliest working of gold in the Balkans or the sudden emergence of distinctive tin-bronze working in Southeast Asia should be seen. 

The richest ore deposits were found in mountain areas as Thornton (2009) makes clear:

Models for the development of metallurgy in Southwest Asia have for a long time been focussed on research carried out in the lowland regions of the Levant and Mesopotamia. These models do not take into account the different developmental trajectories witnessed in the resource-rich highlands of Anatolia, the Caucasus, and Iran. In this paper, the beginnings of the use and production of metals in Iran will be juxtaposed with a cursory overview of the lowland model (the ‘Levantine Paradigm’) in order to highlight these differences. By synthesizing data from a number of current research projects exploring the early metallurgy of the Iranian Plateau, this paper demonstrates how at least one of the highland regions of Southwest Asia was at the very forefront of technological innovation from the seventh through the second millennium BC.  

I had planned to write a separate post on the interplay between metallurgy and the rise in social complexity that led to the spread of (at least some branches of-) Indo-European and Semitic during time, but this is probably as good a place as any to summarize the argument:

The practice of metallurgy launched the first globalization: in order to produce high quality metal objects, one needed a variety of specialized workers: prospectors, miners, metalworkers. The necessary ores do not occur everywhere on the map, and production requires a complex logistic operation to manage resources and talent. One needed, in addition, to establish a network of traders and warriors to carry out and supervise the trade, since demand for metal objects was wide and not limited to the vicinity of their production.

Production and trade networks facilitated the flow of ideas, and necessitated the flow of peoples, both because expertise was non-local, and also because the producers wanted to supervise their profitable business. There is an advantage to being an early adopter of new technology; many of the shifts in power in world history depended on a technology differential (European guns in the New World, mounted archers on the Eurasian steppe, triremes in the Mediterranean, Macedonian long-spears vs. Persian light infantry being some examples).

The technology differential eventually dissipates as everyone gets access to the new inventions. This process may take several centuries, but in the meantime those monopolizing them enjoy a triple advantage:

1. There is demand for their product
2. They have the better weapons
3. They are part of broader communities that can muster resources against anyone who crosses them

It is no accident that the Bronze Age started with technological innovation and ended up in a series of military conflicts. What began as a transformation of Neolithic communities by monopolizing guilds of the bearers of the new technologies ended up with everyone having access to them, and of course they went to war.

Getting back to the topic of Panagiaris' dissertation, I might try my hand at translating some interesting portions. These will be posted as updates in the space below.

Late Minoan IB destructions not followed by Mycenaean immigration

This is an important contribution which falsifies the theory that the destructions of the Minoan palaces associated with the Late Minoan IB involved the coming of Mycenaean elites to Crete, by using a combination of strontium isotope analysis (which captures first-generation migrants) and biodistance analysis (which reveals no pattern of greater affinity of post-LMIB populations to mainland Greek samples.

However, this is interesting:

Therefore these results suggest a gradual rounding of the cranial shape for the Central Cretan population in the course of the Bronze Age, resulting from the increase of the cranial breadth in relation to cranial length. They further provide negative evidence for a disruption of the biological history of the Knossos population following the LMIB destructions due to an increase in the biodistance between the samples dating immediately prior and following the destructions.  

The gradual rounding of the cranial shape of the Central Cretan population over the course of the Bronze Age and the very similar shape of the Gypsades, Sellopoulo and Mavrospelio crania can be more clearly appreciated by plotting the Cranial Index (100*maximum cranial breadth/glabello – occipital length) data. The Cranial Index describes the cranial shape and higher cranial indices reflect a more rounded cranium. In Figure 7, the Cranial Indices for all the above-mentioned Central Cretan population samples are plotted in chronological order, from the Early to Late Bronze Age. Cranial Indices were calculated separately for males and females from each sample.  

The gradual increase in Cranial Index over the Bronze Age most probably reflects gene-flow from population/s biologically different from the Early Bronze Age Cretan population and from inter-population biological interactions (admixture) in the succeeding periods. An alternative interpretation implicating the thermoregulatory model of Beals et al. (1984) and adaptation to colder climatic conditions carries less weight. 

This might be consistent with J. Lawrence Angel's detection of a "Dinaroid-Alpine central trend" of Bronze Age invaders of Greece, as well as the well-known contemporary physiognomy of the historical Hittites and the physical anthropological evidence for them:

Senyurek (1951d, pp. 614-15) concludes that "the majority of the Chalcolithic and Copper Age inhabitants of Anatolia were dolichocephals of mainly Eurafrican and Mediterranean types, and that the brachycephals, probably representing the invaders, were rare in these periods. This study has further supported the conclusion that the earliest inhabitants of Anatolia were longheaded, and that the brachycephals came in subsequently. "The craniological evidence indicates that an invasion of brachycephals into Anatolia took place during the Chalcolithic period and that it was followed by a second invasion, bringing in the brachycephalic elements to Alaca Huyuk and other Copper Age sites, probably at about the middle of the Copper Age. The next invasion of brachycephals, which was more important and extensive than the previous ones, occurred at about 2000 B.C. This was made by the Hittites who were predominantly of the classical Alpine type."  

While there does not appear to be specific evidence for a new population element arriving in Crete after the LMIB destructions, the pattern during the Bronze Age is probably consistent with an intrusive population.

If we accept that the European Neolithic island-hopped to Greece from the East and thence spread north and east into Europe, it is peculiar that ancient DNA from Neolithic Europeans is dominated by Y-haplogroups I2b and G2a (missing the dominant Anatolian J2 haplogroup) and by a "Mediterranean" autosomal makeup (missing the dominant Anatolian West_Asian component). As I have previously argued, this suggests a sea change in the genetic makeup of Anatolia itself since the early Neolithic, and a Bronze Age migration of J2/West_Asian brachycephals into Anatolia, mainland Greece and Crete would be one possible agent for that development.

Late Minoan IB destructions and cultural upheaval on Crete: A bioarchaeological perspective

Nafplioti, Argyro

This paper discusses representative results from strontium isotope ratio (87Sr/86Sr) and biodistance analyses of archaeological human skeletal material carried out to assess the validity of the theory of a LMIB (ca. 1490/1470 BC) Mycenaean invasion of Crete and imposed political domination of Knossos, and thus shed more light onto the question of the LMIB destructions and the subsequent cultural upheaval on the island. These analyses show that the people buried in post- LMIB tombs at Knossos, traditionally associated with Mycenaeans based on material culture evidence, were in fact born locally and not in the Argolid. Further, the analyses presented reject the possibility that these people may represent the descendants of immigrants from the latter region. Additional negative evidence for the theory tested comes from further cranial and dental morphological analyses presented in the author’s doctoral thesis, as well as the material culture itself, briefly discussed here.

Link

Craniological and dental signatures of Out-of-Armenia

From the paper on the craniological results:

One can see a clear link between the Armenian highlands samples and the Western Europe samples (the Arcvakar sample - 17 close phenetic links are revealed). The samples from the Georgia (Samtavro /Late Bronze Age - II period) and Iran (Tepe Gissar III), Uzbekistan (Sapallitepe) are identified as the samples with closest affinities samples from Ukraine (Shirochanski) and Poland, Germany (Corded Ware culture) in particular (figure 3). This suggests that some of the European genes do actually stem from this area. So, mediterranean connections from Armenian highlands, Georgia and Central Asia are distinctly fixed in Western Europe and in the Middle-Late Bronze Age. 

... 

If true, it is suggested that the dispersal of the Indo-European languages have been accompanied by migration and some gene flow from the Armenian highlands homeland to the various historical seats of the Indo-European languages. The different rates of genetic drift and external gene flow may have contributed to the morphological differentiation and diversification amongst the different Eurasian populations. Cluster analysis has revealed a craniological series having analogies (on a complex of craniometric, odontologic characters) with representatives of the population of the Armenian highlands, the Caucasus, the Near East and Central Asia. The initial starting area (or one of the intermediate areas), as indicated by the anthropological data, would seem to be the Armenian highlands, and the Caucasus as a whole (Figure 7).

Asian Culture and History Vol. 4, No. 2; July 2012
doi:10.5539/ach.v4n2p48


Bioarchaeological Analysis Mutual Relations of Populations Armenian Highlands and Eurasia Using Craniological and Dental Nonmetric Traits

Anahit Yu. Khudaverdyan1 Institute of Archaeology and Еthnography National Academy of Science, Republic of Armenia

Abstract

Undertaken here is a multidimensional craniometric analysis of more than 254 ethnic groups of the Neolithic and Bronze Ages from the territory of Eurasia. On the basis of the received information, cluster analysis was done and has shown the genetic condensations of ethnoses and vectors of relatives or, conversely, distinctions between them. Craniometric and odontologic investigation of the Bronze Age is interesting and in connection with discussion about the origin of Indo-Europeans and about the place of their ancestral home. Different aspects of the problem of the ancestral home of Indo-Europeans are far from completely resolved and generate lively debate in the pages of scientific publications. New anthropological data allowed identification of alien Mediterranean characteristics influencing various ethnic Eurasian groups and revealed evidence of a migratory stream from the Armenian highlands and the Caucasus. This research provided new evidence of patterns of ethnic contact and intermixture in Western Eurasia

Link

Cranial variation and the transition to agriculture in Europe

Students of physical anthropology won't be surprised that Pinhasi and von Cramon-Taubadel find that the Neolithic and pre-Neolithic populations in Europe were differentiated cranially as they were apparently genetically.

It has long been recognized that the ancient European population was different than the Upper Paleolithic population of the continent. Carleton Coon ascribed this differentiation to migration of narrow-faced Mediterraneans into the territory of the robust broad-faced Upper Paleolithics. Ilse Schwidetzky also viewed migration from the Southeast of gracile Mediterraneans who gradually replaced broad-faced Cro-Magnoids.

So, it is nice to read that the re-analysis of a wide assortment of skulls on 15 cranial variables has revealed that:

The major shape differences separating hunter-gatherer Mesolithic populations and farming Neolithic populations are coded by PC1 with Neolithic specimens having longer and taller vaults, and Mesolithic specimens having larger, and broader faces.

There are two (or three) puzzles in European prehistory:

• How the robust, low-skulled, broad-faced hunter-gatherers became more high-skulled, narrow-faced and gracile
• How the latter became brachycephalized until early modern times
• Why they have become partially debrachycephalized in the most recent of times

Anthropologists have tended to favor either migration or adaptation to explain these trends, with some even suggesting simple phenotypic plasticity without any major genetic change. It is now clear that -whatever the role of adaptation or plasticity- the Upper Paleolithic population of Europe did not simply change to become more gracile on its own, but was affected by an already gracile population of foreign origin who set the ball rolling. There is already work on the genetic basis of facial structure, so, it is quite possible that eventually we'll be able to track directly the genetic changes underlying the phenotypic transformation of Europeans.

From the paper:

Nonetheless, the craniometric analysis allows us to discern certain patterns. For example, the ‘Forest Neolithic’ specimens are clearly much more similar to other Mesolithic hunter-gatherers than to Neolithic farmers in terms of their craniometric shape, suggesting a large degree of cultural diffusion in this region. However, it is also evident that the earliest potential colonisers of southeast and central Europe are very similar to the Anatolian Çatal Höyük population, congruent with an initial demic diffusion from the Near East/Anatolia.

The "Forest Neolithic" included pottery-using groups of eastern Europe (hence Neolithic, since pottery is one of the hallmarks of that period), but should not be confused with the early agriculturalists who apparently practiced farming without pottery early on in the Near East and Greece, and then acquired pottery and expanded with it into the rest of Europe, together with their full "package" of domesticated crops and animals.

Human Biology vol. 84

Cranial variation and the transition to agriculture in Europe

Ron Pinhasi, Noreen Von Cramon-Taubadel

Abstract

Debates surrounding the nature of the Neolithic demographic transition in Europe have historically centred on two opposing models; a 'demic' diffusion model whereby incoming farmers from the Near East and Anatolia effectively replaced or completely assimilated indigenous Mesolithic foraging communities and an 'indigenist' model resting on the assumption that ideas relating to agriculture and animal domestication diffused from the Near East, but with little or no gene flow. The extreme versions of these dichotomous models have been heavily contested primarily on the basis of archaeological and modern genetic data. However, in recent years there has been a growing acceptance of the likelihood that both processes were ongoing throughout the Neolithic transition and that a more complex, regional approach is required to fully understand the change from a foraging to a primarily agricultural mode of subsistence in Europe. Craniometric data have been particularly useful for testing these more complex scenarios, as they can reliably be employed as a proxy for the genetic relationships amongst Mesolithic and Neolithic populations. In contrast, modern genetic data assume that modern European populations accurately reflect the genetic structure of Europe at the time of the Neolithic transition, while ancient DNA data are still not geographically or temporally detailed enough to test continent-wide processes. Here, with particular emphasis on the role of craniometric analyses, we review the current state of knowledge regarding the cultural and biological nature of the Neolithic transition in Europe.

Link

Big eye sockets compensate for low ambient light levels in humans

Biology Letters doi: 10.1098/rsbl.2011.0570


Latitudinal variation in light levels drives human visual system size

Eiluned Pearce and Robin Dunbar

Ambient light levels influence visual system size in birds and primates. Here, we argue that the same is true for humans. Light levels, in terms of both the amount of light hitting the Earth's surface and day length, decrease with increasing latitude. We demonstrate a significant positive relationship between absolute latitude and human orbital volume, an index of eyeball size. Owing to tight scaling between visual system components, this will translate into enlarged visual cortices at higher latitudes. We also show that visual acuity measured under full-daylight conditions is constant across latitudes, indicating that selection for larger visual systems has mitigated the effect of reduced ambient light levels. This provides, to our knowledge, the first support that light levels drive intraspecific variation in visual system size in the human population.

Link

AAPA 2012 abstracts (Part 3)

Continuing from Part 2.


An analysis of the Klasies River hominins using a hybrid model.
LILY MALEKFAR. Anthropology, Northern Illinois University.

Current research indicates that modern Homo sapiens originated in East Africa and then migrated across Africa as well as out of Africa, where they encountered archaic hominins. The Klasies River Main site (KRM) in South Africa is one location where there is evidence that modern and archaic Homo sapiens may have interacted. As Smith and other researchers have suggested, the KRM mandibular sample, in particular, exhibits significant size and morphological variability, which counters claims that the KRM specimens are fully modern.
The null hypothesis predicts that KRM’s range of variation does not significantly differ from the ranges of variation indicated in the comparative samples, including Sima de los Huesos, Krapina, Skhul, Qafzeh, and the Northern Illinois University (NIU) Collection, the latter containing specimens classified as modern Homo sapiens from India. If the null hypothesis is rejected, this would be tentative support that the KRM sample may possibly be a hybrid sample. This study examines first and second mandibular molar lengths and widths as well as mandibular corpus height and breadth in adult hominins and compares patterns of variation using the coefficient of variation.
The results demonstrate that the KRM sample is markedly more variable than any of the comparative samples, which rejects the null hypothesis and is one possible indicator of an admixed sample at KRM. This study is limited by small sample sizes for KRM. This and the fact that KRM spans several thousand years may impact these results.

The origins of dental modernity.

SHARA E. BAILEY1,2 and JEAN-JACQUES HUBLIN2.
Research over the past decade has established that the study of dental morphological characters is a useful and important tool for interpreting the later stages of human evolution. A good deal of this research has focused on identifying dental characters that are relevant specifically to the distinction between Neandertals and H. sapiens, and more broadly to the question of modern human origins. However, while the dental patterns of certain recent H. sapiens populations have been described as primitive (e.g., Sub-Saharan Africans) or derived (Northeast Asians) relative to other groups, no study to date has proposed a dental pattern that characterizes H. sapiens as a species. To this end, this study investigates (1) whether or not there is a unique dental pattern in H. sapiens; (2) if so, which traits comprise this pattern; and (3) when, during the course of human evolution, these traits emerge. Our results show that size notwithstanding, H. sapiens has few uniquely derived dental traits that distinguish them from other hominins. These include the U-shaped fissure pattern of the lower P4, relatively flat, featureless upper incisors that are buccolingually narrow, lower molars lacking a hypoconulid and lower molars lacking any form of trigonid crest on enamel and dentine surfaces. Early H. sapiens from Qafzeh, Klasies River Mouth and Jebel Irhoud possess some of these characters. Interestingly, none of the recently discovered teeth from Qesem Cave, Israel exhibit any derived H. sapiens non-metric traits, while the molars of H. floresiensis are derived toward the H. sapiens condition.

Endocranial shape in early modern humans.

SIMON NEUBAUER, PHILIPP GUNZ and JEAN-JACQUES HUBLIN.
Humans have more globular brains and therefore endocasts than our extant and extinct relatives: chimpanzees and Neanderthals both have anterioposteriorly elongated endocasts. Based on an ontogenetic series of recent modern humans, we have previously shown that this modern human globular shape develops directly after birth during an ontogenetic phase that is absent in chimpanzees and Neanderthals. However, it is unclear at which point in the evolution of our species this unique pattern of brain development appeared.
Here, we aim to trace its evolutionary origin. Based on the shape of fossil adult humans, we investigate the morphological evolution of Homo sapiens endocasts using geometric morphometrics. Investigating representatives of H. sapiens from different time periods (comprising samples from Jebel Irhoud, Qafzeh, Skhul, Mladec, Cro-Magnon) makes it possible to assess when and how (gradually or rapidly) this developmental phase appeared in the course of recent human evolution. As several relevant fossils are fragmentary and partly deformed, they require reconstruction before they can be analyzed. To this end, we generate and reconstruct virtual endocasts based on CT scans. We first use mirror-imaging and segmentation techniques, and then the thin-plate-spline interpolation function for reference-based reconstruction. Generating multiple reconstructions based on landmarks of 60 recent human endocasts, we keep track of the reconstruction uncertainty throughout the shape analysis. We document temporal trends of endocranial shape within anatomically modern humans during the Late Pleistocene and discuss potential implications for the evolution of the modern human brain.