Clustering folk tales

Clustering folk tales

Proc. R. Soc. B 7 April 2013 vol. 280 no. 1756
doi: 10.1098/rspb.2012.3065

Population structure and cultural geography of a folktale in Europe 

Robert M. Ross et al.

Despite a burgeoning science of cultural evolution, relatively little work has focused on the population structure of human cultural variation. By contrast, studies in human population genetics use a suite of tools to quantify and analyse spatial and temporal patterns of genetic variation within and between populations. Human genetic diversity can be explained largely as a result of migration and drift giving rise to gradual genetic clines, together with some discontinuities arising from geographical and cultural barriers to gene flow. Here, we adapt theory and methods from population genetics to quantify the influence of geography and ethnolinguistic boundaries on the distribution of 700 variants of a folktale in 31 European ethnolinguistic populations. We find that geographical distance and ethnolinguistic affiliation exert significant independent effects on folktale diversity and that variation between populations supports a clustering concordant with European geography. This pattern of geographical clines and clusters parallels the pattern of human genetic diversity in Europe, although the effects of geographical distance and ethnolinguistic boundaries are stronger for folktales than genes. Our findings highlight the importance of geography and population boundaries in models of human cultural variation and point to key similarities and differences between evolutionary processes operating on human genes and culture.

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Complex history of the olive tree

Complex history of the olive tree

Proc. R. Soc. B 7 April 2013 vol. 280 no. 1756
doi: 10.1098/rspb.2012.2833

The complex history of the olive tree: from Late Quaternary diversification of Mediterranean lineages to primary domestication in the northern Levant

G. Besnard et al.

The location and timing of domestication of the olive tree, a key crop in Early Mediterranean societies, remain hotly debated. Here, we unravel the history of wild olives (oleasters), and then infer the primary origins of the domesticated olive. Phylogeography and Bayesian molecular dating analyses based on plastid genome profiling of 1263 oleasters and 534 cultivated genotypes reveal three main lineages of pre-Quaternary origin. Regional hotspots of plastid diversity, species distribution modelling and macrofossils support the existence of three long-term refugia; namely the Near East (including Cyprus), the Aegean area and the Strait of Gibraltar. These ancestral wild gene pools have provided the essential foundations for cultivated olive breeding. Comparison of the geographical pattern of plastid diversity between wild and cultivated olives indicates the cradle of first domestication in the northern Levant followed by dispersals across the Mediterranean basin in parallel with the expansion of civilizations and human exchanges in this part of the world.

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mtDNA from southeastern Kenyan Bantu

mtDNA from southeastern Kenyan Bantu

Am J Phys Anthropol DOI: 10.1002/ajpa.22227

Mitochondrial DNA Diversity in Two Ethnic Groups in Southeastern Kenya: Perspectives from the Northeastern Periphery of the Bantu Expansion

Ken Batai et al.

The Bantu languages are widely distributed throughout sub-Saharan Africa. Genetic research supports linguists and historians who argue that migration played an important role in the spread of this language family, but the genetic data also indicates a more complex process involving substantial gene flow with resident populations. In order to understand the Bantu expansion process in east Africa, mtDNA hypervariable region I variation in 352 individuals from the Taita and Mijikenda ethnic groups was analyzed, and we evaluated the interactions that took place between the Bantu- and non-Bantu-speaking populations in east Africa. The Taita and Mijikenda are Bantu-speaking agropastoralists from southeastern Kenya, at least some of whose ancestors probably migrated into the area as part of Bantu migrations that began around 3,000 BCE. Our analyses indicate that they show some distinctive differences that reflect their unique cultural histories. The Taita are genetically more diverse than the Mijikenda with larger estimates of genetic diversity. The Taita cluster with other east African groups, having high frequencies of haplogroups from that region, while the Mijikenda have high frequencies of central African haplogroups and cluster more closely with central African Bantu-speaking groups. The non-Bantu speakers who lived in southeastern Kenya before Bantu speaking groups arrived were at least partially incorporated into what are now Bantu-speaking Taita groups. In contrast, gene flow from non-Bantu speakers into the Mijikenda was more limited. These results suggest a more complex demographic history where the nature of Bantu and non-Bantu interactions varied throughout the area.

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Late Neandertal survival in Iberia questioned

Late Neandertal survival in Iberia questioned

Neanderthal remains point to earlier extinction

In the latest study1, Higham and his former graduate student Rachel Wood, now at the Australian National University in Canberra, tried to date remains from 11 sites on the Iberian Peninsula using their decontamination methods. Previous efforts put the remains as young as 36,000 years old.

However, Wood and Higham found that just two of the sites — Jarama, outside Madrid, and Cueva del Boquete de Zafarraya, near the southern tip of Spain — contained bones with enough carbon to be dated. Their work suggests that these remains are more than 45,000 years old, with some older than 50,000 years, the practical limit of carbon dating. Wood says that the team’s study calls into question evidence that the last populations of Neanderthals found refuge in the Iberian Peninsula.

PNAS doi: 10.1073/pnas.1207656110

Radiocarbon dating casts doubt on the late chronology of the Middle to Upper Palaeolithic transition in southern Iberia

Rachel E. Wood et al.

It is commonly accepted that some of the latest dates for Neanderthal fossils and Mousterian industries are found south of the Ebro valley in Iberia at ca. 36 ka calBP (calibrated radiocarbon date ranges). In contrast, to the north of the valley the Mousterian disappears shortly before the Proto-Aurignacian appears at ca. 42 ka calBP. The latter is most likely produced by anatomically modern humans. However, two-thirds of dates from the south are radiocarbon dates, a technique that is particularly sensitive to carbon contaminants of a younger age that can be difficult to remove using routine pretreatment protocols. We have attempted to test the reliability of chronologies of 11 southern Iberian Middle and early Upper Paleolithic sites. Only two, Jarama VI and Zafarraya, were found to contain material that could be reliably dated. In both sites, Middle Paleolithic contexts were previously dated by radiocarbon to less than 42 ka calBP. Using ultrafiltration to purify faunal bone collagen before radiocarbon dating, we obtain ages at least 10 ka 14C years older, close to or beyond the limit of the radiocarbon method for the Mousterian at Jarama VI and Neanderthal fossils at Zafarraya. Unless rigorous pretreatment protocols have been used, radiocarbon dates should be assumed to be inaccurate until proven otherwise in this region. Evidence for the late survival of Neanderthals in southern Iberia is limited to one possible site, Cueva Antón, and alternative models of human occupation of the region should be considered.

Link

"In Africa" project

"In Africa" project

The new 5-year "In Africa" project headed by Marta Mirazon Lahr has a wonderful website filled with information. From the Aims section:


"The project hopes to achieve five main goals:

1. to increase significantly the number of human and other mammalian fossils in East Africa dating to the last 250,000 years;
2. to map changes in human morphology, behaviour and occupation in different basins of East Africa in the period before and after the main modern human dispersals across and out of Africa;
3. to map the character and timing of the Middle to Later Stone Age transition in the Central Rift Valley;
4. to integrate the human prehistoric record with local palaeoenvironmental data to explore the role climate change and its expression in the African tropics may have played in our recent evolutionary history;
5. to increase the scientific and public awareness of how important it is to understand what happened in Africa in order to understand why Homo sapiens and its diversity evolved."

An example of the information that can be found in this site is this list of Middle Pleistocene Sub-Saharan African fossils (pdf). Please note that some of the given dates (such as that of Broken Hill/Kabwe) are controversial. The e-library is also full of a large number of  papers and is a very useful resource.

Aztec conquest of Xaltocan led to population replacement

Aztec conquest of Xaltocan led to population replacement

This study represents a good example of how ancient DNA analysis can supplement traditional archaeology. Issues of population replacement/continuity are often encountered in archaeology, especially when there are traditions of conquest/resettlement, or such events might be hypothesized by changes in the material record.

But, such events are often difficult to interpret, because people living through periods of turmoil might have a tendency to exaggerate their importance, while culture is malleable and may shift without large-scale population replacement.

Am J Phys Anthropol DOI: 10.1002/ajpa.22152

The Genetic Impact of Aztec Imperialism: Ancient Mitochondrial DNA Evidence From Xaltocan, Mexico 

Jaime Mata-Mıguez et al.

In AD 1428, the city-states of Tenochtitlan, Texcoco, and Tlacopan formed the Triple Alliance, laying the foundations of the Aztec empire. Although it is well documented that the Aztecs annexed numerous polities in the Basin of Mexico over the following years, the demographic consequences of this expansion remain unclear. At the city-state capital of Xaltocan, 16th century documents suggest that the site's conquest and subsequent incorporation into the Aztec empire led to a replacement of the original Otomí population, whereas archaeological evidence suggests that some of the original population may have remained at the town under Aztec rule. To help address questions about Xaltocan's demographic history during this period, we analyzed ancient DNA from 25 individuals recovered from three houses rebuilt over time and occupied between AD 1240 and 1521. These individuals were divided into two temporal groups that predate and postdate the site's conquest. We determined the mitochondrial DNA haplogroup of each individual and identified haplotypes based on 372 base pair sequences of first hypervariable region. Our results indicate that the residents of these houses before and after the Aztec conquest have distinct haplotypes that are not closely related, and the mitochondrial compositions of the temporal groups are statistically different. Altogether, these results suggest that the matrilines present in the households were replaced following the Aztec conquest. This study therefore indicates that the Aztec expansion may have been associated with significant demographic and genetic changes within Xaltocan.

Link

40,000-year old "Lion Man"

40,000-year old "Lion Man"

Ice Age Lion Man is world’s earliest figurative sculpture

Even more exciting than the discovery of new pieces, the sculpture’s age has been refined using radio-carbon dating of other bones found in the strata. This reveals a date of 40,000 years ago, while until recently it was thought to be 32,000 years old. Once reconstruction is completed, several tiny, unused fragments of the mammoth ivory are likely to be carbon dated, and this is expected to confirm the result.

This revised dating pushes the Lion Man right back to the oldest sculptures, which have been found in two other caves in the Swabian Alps. These rare finds are dated at 35,000 to 40,000 years, but the Lion Man is by far the largest and most complex piece. A few carved items have been found in other regions which are slightly older, but these have simple patterns, not figuration.

What was striking about the sculptor of the Lion Man sculptor is that he or she had a mind capable of imagination rather than simply representing real forms. As Cook says, it is “not necessary to have a brain with a complex pre-frontal cortex to form the mental image of a human or a lion—but it is to make the figure of a lion-man”. The Ulm sculpture therefore sheds further light on the evolution of homo sapiens.

I have sometimes wondered whether therianthropic figures really represent an abstract blending of forms (which would require the mental conception of a non-actual creature), or a stylized depiction of a real man wearing (like Hercules) a lion's head.

It's not inconceivable that Ice Age hunters might "wear their prey on their head", just as later hunters used antlers for the same purpose. This may be a more prosaic explanation (Big Men projecting their power and prowess as a reflection of the dangerous animals they killed) compared to the idea of artists envisioning  an imaginary being.