Mitochondrial DNA unsuitable to test for IBD, and undersampling genomes show biased time and rate estimates

Two interesting papers questioning previous methods have been published.

Open access Mitochondrial DNA is unsuitable to test for isolation by distance, by Teske et al. Scientific Reports (2018) 8:8448.

Abstract (emphasis mine):

Tests for isolation by distance (IBD) are the most commonly used method of assessing spatial genetic structure. Many studies have exclusively used mitochondrial DNA (mtDNA) sequences to test for IBD, but this marker is often in conflict with multilocus markers. Here, we report a review of the literature on IBD, with the aims of determining (a) whether significant IBD is primarily a result of lumping spatially discrete

Read the rest “Mitochondrial DNA unsuitable to test for IBD, and undersampling genomes show biased time and rate estimates”

On Latin, Turkic, and Celtic – likely stories of mixed societies and little genetic impact

celtic-europe-national-geographic

Recent article on The Conversation, The Roman dead: new techniques are revealing just how diverse Roman Britain was, about the paper (behind paywall) A Novel Investigation into Migrant and Local Health-Statuses in the Past: A Case Study from Roman Britain, by Redfern et al. Bioarchaeology International (2018), among others.

Interesting excerpts about Roman London:

We have discovered, for example, that one middle-aged woman from the southern Mediterranean has black African ancestry. She was buried in Southwark with pottery from Kent and a fourth century local coin – her burial expresses British connections, reflecting how people’s communities and lives

Read the rest “On Latin, Turkic, and Celtic – likely stories of mixed societies and little genetic impact”

The fast spread of Neolithic farmers in the western Mediterranean

Recent open access Symbols in motion: Flexible cultural boundaries and the fast spread of the Neolithic in the western Mediterranean, by Rigaud, Manen, García-Martínez de Lagrán, PLOS One (2018).

Abstract (emphasis mine):

The rapid diffusion of farming technologies in the western Mediterranean raises questions about the mechanisms that drove the development of intensive contact networks and circulation routes between incoming Neolithic communities. Using a statistical method to analyze a brand-new set of cultural and chronological data, we document the large-scale processes that led to variations between Mediterranean archaeological cultures, and micro-scale processes responsible for the transmission of cultural practices

Read the rest “The fast spread of Neolithic farmers in the western Mediterranean”

Pre-Roman and Roman mitogenomes from Southern Italy

vagnari-cemetery-haplogroups-superimposed

Ph.D. thesis Assessing Migration and Demographic Change in pre-Roman and Roman Period Southern Italy Using Whole-Mitochondrial DNA and Stable Isotope Analysis, or The Biogeographic Origins of Iron Age Peucetians and Working-Class Romans From Southern Italy, by Matthew Emery, McMaster University (2018).

Abstract (emphasis mine):

Assessing population diversity in southern Italy has traditionally relied on archaeological and historic evidence. Although informative, these lines of evidence do not establish specific instances of within lifetime mobility, nor track population diversity over time. In order to investigate the population structure of ancient South Italy I sequenced the mitochondrial DNA (mtDNA) from 15

Read the rest “Pre-Roman and Roman mitogenomes from Southern Italy”

How an empire of steppe nomads coped with environmental stress

uyghur-empire

Recent paper (behind paywall), Environmental Stress and Steppe Nomads: Rethinking the History of the Uyghur Empire (744–840) with Paleoclimate Data, by Di Cosmo et al. JINH (2018) XLVIII(4):439-463.

Abstract (emphasis mine):

Newly available paleoclimate data and a re-evaluation of the historical and archaeological evidence regarding the Uyghur Empire (744–840)—one of several nomadic empires to emerge on the Inner Asian steppe—suggests that the assumption of a direct causal link between drought and the stability of nomadic societies is not always justified. The fact that a severe drought lasting nearly seven decades did not cause the Uyghur Empire to collapse, to

Read the rest “How an empire of steppe nomads coped with environmental stress”

Homo sapiens in Arabia by 85,000 years ago

Homo sapiens in Arabia by 85,000 years ago, by Groucutt et al. Nat Ecol. Evol. (2018).

Abstract (emphasis mine):

Understanding the timing and character of the expansion of Homo sapiens out of Africa is critical for inferring the colonization and admixture processes that underpin global population history. It has been argued that dispersal out of Africa had an early phase, particularly ~130–90 thousand years ago (ka), that reached only the East Mediterranean Levant, and a later phase, ~60–50 ka, that extended across the diverse environments of Eurasia to Sahul. However, recent findings from East Asia and Sahul challenge this

Read the rest “Homo sapiens in Arabia by 85,000 years ago”

Distribution of Southern Iberian haplogroup H indicates exchanges in the western Mediterranean

Recent open access paper The distribution of mitochondrial DNA haplogroup H in southern Iberia indicates ancient human genetic exchanges along the western edge of the Mediterranean, by Hernández, Dugoujon, Novelletto, Rodríguez, Cuesta and Calderón, BMC Genetics (2017).

Abstract (emphasis mine):

Background
The structure of haplogroup H reveals significant differences between the western and eastern edges of the Mediterranean, as well as between the northern and southern regions. Human populations along the westernmost Mediterranean coasts, which were settled by individuals from two continents separated by a relatively narrow body of water, show the highest frequencies of mitochondrial haplogroup H. These

Read the rest “Distribution of Southern Iberian haplogroup H indicates exchanges in the western Mediterranean”

The uneasy relationship between Archaeology and Ancient Genomics

Allentoft Corded Ware

News feature Divided by DNA: The uneasy relationship between archaeology and ancient genomics, Two fields in the midst of a technological revolution are struggling to reconcile their views of the past, by Ewen Callaway, Nature (2018) 555:573-576.

Interesting excerpts (emphasis mine):

In duelling 2015 Nature papers6,7the teams arrived at broadly similar conclusions: an influx of herders from the grassland steppes of present-day Russia and Ukraine — linked to Yamnaya cultural artefacts and practices such as pit burial mounds — had replaced much of the gene pool of central and Western Europe around

Read the rest “The uneasy relationship between Archaeology and Ancient Genomics”