A qualified opinion on the Eastern Gravettian

The always interesting Aggersbach's Paleolithic Blog offers today an entry pondering the Eastern Gravettian and the so-called Willendorf-Kostenki complex. You probably want to read it in full but in any case I appreciate a pondered opinion on these matters, which may help us to understand better the overall process of the European Upper Paleolithic. 

Stone saws from Kostenki

My pick is:

In my view, the extremely rich archaeological record of the east European plain clearly supports the two-stage concept of an eastern Gravettian with occasional leaf point production, followed by a Gravettian with (Micro)-Gravettes, backed microliths and shouldered points (Mitoc Malu Galben in the Pruth valley; Molodova 5, layers VIII and VII; Molodova 1, lower layer; Korman’ 4, layers VII and VI; Voronovitsa 1, upper layer; and Babin I in the Dnester river basin, Khotylevo 2 in the Desna river basin).

More at Aggsbach's Paleolithic Blog.

Also mentioned, as the best approximation to a non-existing online paper in English about the Willendorf-Kostenki complex is an article at another fabulous and veteran site: Don's Maps, from which I'm borrowing some illustrations to complement this entry.

Reconstructed Kostenki tent/home, one of those not built with mammoth bones

Cis-regulatory variability has almost no geographic structure

That is what a new paper has found:

Barbara E. Stranger et al., Patterns of Cis Regulatory Variation in Diverse Human Populations. PLoS Genetics 2012. Open access.

Cis-regulatory elements are key pieces of the overall codification of the genome. The main finding of this paper is that they show almost no geographic structure, that virtually all variation in these key elements is inter-individual and not among populations.

From Supplemental Figure 1 - PC analysis

As you can see in the PCA plot, the inter-population variation is most subtle, almost impossible to discern with so much overlap. The lack of structure repeats for the other components.

Laos inhabited by H. sapiens since maybe 56,000 years ago?

Just a quick note because I really could not find too much.

I just read at a very succint note at Science Daily that:

Researchers have discovered the oldest known human remains in Southeast Asia, a partial human skull dating to at least 40,000 years ago. Excavations at Tam Pa Ling cave in northern Laos produced a dozen pieces from a Stone Age person’s skull, including a skullcap and a lower jaw, anthropologist Laura Shackelford of the University of Illinois at Urbana-Champaign reported April 14. Small front teeth, a rounded brain case and other traits identify the reassembled fossil as a modern Homo sapiens, Shackelford said. The find supports proposals that at least some human migrations out of Africa around 100,000 years ago followed a southern route that led to Southeast Asia.

Nothing more of relevance. I could find a paper (ppv) by Dr. Shackleford on Laos but it discusses another cave and much more recent dates (c. 15 Ka ago).

On the other hand I found a paper on another Laotian cave by different authors which mentions undefined human presence c.56 Ka ago:

Valéry Zeitoun et al, Multi-millennial occupation in northwestern Laos: Preliminary results of excavations at the Ngeubhinh Mouxeu rock-shelter. Comptes Rendus Palevol 2011. Pay per view.

Abstract

With over half a century of political instability, resulting from armed conflicts, decolonisation and the Cold War, archaeological investigations in Laos have been rare, leaving little more than a blank page in the chapter of Southeast Asia's prehistory. Recent research has shown that Laos holds a rich prehistoric heritage. In conjunction with the research initiated by J. White who conducted the first professional archaeological survey of northern Laos since decades, we have extended the investigations to the Luang Namtha province. This work allowed us to gather important data about Hoabinhian stone tool assemblages and former cultures. In particular, the archaeological remains and dating from the Ngeubhinh Mouxeu rock-shelter indicate that this mountainous region of Laos has been inhabited over a long period of time that possibly spans as far back as 56,000 ± 3000 BP.

While, by the moment, I ignore many details, I believe it is very interesting to mention as the early colonization of SE Asia by our species is still not well understood (and yet may be critical to understand all, or at the very least much, of Eurasian, plus aboriginal Australasian and American origins).

With due caution, I think we can infer from these and other less direct (Indian and Arabian archaeology) or more controversial materials (Liujiang skull, Luzon foot bone, speculations about very early colonization of Australia) that the colonization of SE Asia by our kind can be traced to at least that date of 56 Ka ago, probably even earlier.


Update (Aug 21): see this newer entry.

Epipaleolithic paddles found in Danish waters

Paddles are only part of the hoard of objects made of organic materials rescued from what once was an Epipaleolithic settlement of the Ertebølle culture (c. 5400-3900 BCE): undamaged antler axes (right), wooden knife handles and the skull of a dog had also been preserved underwater at that location, with low oxygen levels, just off the coast.

A quite spectacularly preserved paddle:

Video of cleaning a piece of wood at the Moesgård Museum (no sound):

Source: Science Nordic.


Update (Nov 2012):

A new article also at Science Nordic discusses the paddles and how they have marks (three bars at the side) that are similar in concept but different in the detail of the execution. The shape of the paddles is also different.

My intuition wanted to see in this the execution by people connected by culture and maybe even direct family relationship but separated in time. Although not too much, maybe just one century... Just speculating a bit - other interpretations are perfectly possible, of course.

Claim that Japanese are 60-72% Neolithic

Jomon clay head

An open access letter claims that modern Japanese are 2/3 of Neolithic ancestry (except Ryukyuans, who'd be 2/3 Paleolithic instead).

Yungang He et al., Paleolithic Contingent in Modern Japanese: Estimation and Inference using Genome-wide Data. Nature 2012. Open access. 

The explanation is however not really clear for me and, looking at their own data, I can't really accept such conclusions easily:

Only the yellow component (at K=4), almost totally absent in the Ryukyuans and dominant among North Chinese and Koreans, the likely parent populations of the Yayoi farmers, can be considered to inform the input of such immigrants to Japan. The exact apportions are not detailed anywhere in the letter but it seems to be c. 35% among Koreans (KR-KR) and Shanghai Chinese (CN-SH) and slightly above 20% among North Han (NHan, CHB). 

By comparison mainland Japanese (Japanese, JPT, JP-ML) show c. 10% in most cases. IF the parent proto-Yayoi population would be Koreans, then Japanese would have less than 1/3 Yayoi blood, while if the proto-Yayoi is equated to Northern Han instead, then the result would be at most 50%. 

In the case of Ryukyans, the Yayoi input would be negligible, almost zero. They'd be almost 100% Jomon, assuming this concept applies to the Ryukyu islands at all.

In truth I do not know what to think of this article other than it seems confusing and inconsistent with its own data.

Mitochondrial DNA revision and the Reconstructed Sapiens Reference Sequence (RSRS)

The authors and maintainers of PhyloTree have produced a new build (no. 14) with a long list of changes. However the most important part is probably in an associated paper:

Doron M. Behar et al., A “Copernican” Reassessment of the Human Mitochondrial DNA Tree from its Root. AJHG 2012. Freely accessible when writing this. 

The Copernican adjective is because they hope to replace the use of the rCRS (revised Cambridge Reference Sequence, with the highly derived haplogroup H2a2a1, and arbitrary yet convenient pick back in the day) with the Reconstructed Sapiens Reference Sequence (RSRS) which is also the haplotype of the matrilineal most recent common ancestor of extant Humankind, alias 'Mitochondrial Eve'.

The RSRS is also quite directly comparable to the RNRS (the 'Neanderthal Eve', see Fig. S1), being separated by 122 mutations of the coding region and a few more of the control region (HVR). However while between the 'Neanderthal Eve' and actual Neanderthal sequences there are some 17 coding region mutations (14-21), in our species the distance to the most recent common ancestor is longer, 40-50 coding region mutations (most commonly, from memory) and even more when we count the HVR, as illustrated in figure S2:

Fig. S2 - Distances in Substitution Counts from the RSRS to Extant Haplotypes

This image is particularly interesting because it illustrates what the authors describe as indications for violation of the molecular clock: differences in the in the length of the various branches, which vary wildly from circa 40 to above 70, a difference of almost 2:1 between the extremes.

Oddly enough, in spite of M being closer to the root than N and having on average more mutations to present day sequences, the authors manage to somehow assign a younger age to this haplogroup than to its sister N. But in any case their estimates must be wrong overall because the age attributed to L3'4'6 (71 Ka BP), L3'4 (64 Ka) and L3 (67 Ka) are more recent than the known archaeological evidence for  the migration out-of-Africa which, at the latest, must have happened c. 90-80 Ka ago. The L3 node must be older than these dates therefore.

The authors also propose some nomenclature terminology, notably the use of superscript n for the nodal haplotypes (as opposed to just unclassified sequences, for which we will still use asterisk). That way we can more easily discern a nodal or root H haplotype (Hⁿ) from a mere random unclassified H haplotype (H*). Other proposals for the nomenclature may be more debatable and in some cases they manage to violate them themselves in the supplemental materials.

Whatever my criticisms (everything is debatable and I love a good discussion), I must say that the PhyloTree team deserves my utmost appreciation and respect: before them understanding the human mtDNA landscape was a total mess, now it is possible even for amateurs with a keen interest like myself. Thanks a lot.

See also: Mitochondrial DNA and molecular clock.

Acheulean use of fire confirmed

That is what Francesco Berna and colleagues argue in a new paper:

F. Berna et al., Microstratigraphic evidence of in situ fire in the Acheulean strata of Wonderwerk Cave, Northern Cape province, South Africa. PNAS 2012. Open access.

The findings are dated to at least one million years ago and correspond to the Acheulean period, characterized by bifacial axes and generally attributed to Homo erectus or H. ergaster.

Partly charred bone from Wonderwerk

As the authors explain, previous claims of fire use in this period in East Africa,  the Levant or China have been plagued with controversy. In most cases the controversy stems from the relatively low resolution of the research and the possibility of the fires being natural occurrences. In the case of Zhoukoudian, near Beijing, what was once claimed as product of fire ended being sedimentary deposits. 

This research actually continues the findings of Peter B. Beaumont last year, who claimed (JSTOR, pay-per-view) that the South African cave hosted evidence of fire dated to c. 1.7 Ma.

The evidence included charred vegetal remains and animal bones, these last not completely calcinated, meaning that combustion was under 700 °C. Also remains of ironstone brought intently to the cave and worked in situ (main material of artifacts) show signs of manipulation under heat above 500 °C.

Apparently the fires were produced almost exclusively with light materials such as dry grasses and leaves. While it is not impossible that they might have used wood and then the evidence got lost, the data from bones indicates combustion under 700 °C, what is compatible with fire produced with lighter materials exclusively.

See also: Boston University's site, BU Today.