Monday, December 26, 2016

Homicide Rates Have Declined For Centuries In Europe

Data going back to 1300 CE show a steady decline in homicides everywhere in Europe. The past was a much more violent place than it is today.

89% Of The Vietnamese Share 14 Surnames

The pattern of a small number of surnames accounting for most of the population found in China and Korea is also true of Vietnam where 89% of people have one of fourteen surnames (the link is to the Facebook page of a somewhat regular reader).

The pattern is particularly notable because the Chinese languages (part of the Sino-Tibetan language family), the Korean language (either an isolate, a Korean-Japanese language family, or the Greater Altaic language family) and Vietnamese (part of the Austro-Asiatic language family) are from completely different macro-linguistic language families.

There are historical reasons for this in recorded history. In both Korea and Vietnam, at least, a common pattern was to take the surname of the aristocratic house to which you owed allegiance in the still somewhat feudal era in which surnames were adopted. In Vietnam, some political reversals and turns of fate at critical moments caused members of losing factions to adopt the surnames of winning factions to avoid persecution. I haven't read any accounts of the parallel process in China, but suspect that it is similar. 

Ancient Astronomy On Easter Island

The people of Easter Island kept accurate written records of Halley's Comet and other astronomy observations.
The ancient priest-astronomers constantly watched many heavenly bodies. The record about Halley's Comet of 1682 A.D. has been decoded completely. Good agreement between it and the results of European astronomers is seen. The records about of Halley's Comet of 1835 A.D. as well as about the sun, the moon, Mars and Saturn have been deciphered as well. The obtained information is the basis in order to understand some aspects of the bird-man cult.
Sergei Rjabchikov, "The Ancient Astronomy of Easter Island: The Mamari Tablet Tells (Part 1)" (Preprint December 12, 2016)

Friday, December 23, 2016

Christmas Astronomy

Previously, the most prominent explanation for the Star of Bethlehem was to identify one of many astronomical events in the sky as being the inspiration for the trip of the Magi. However, all the astronomical answers have detailed refutations, and general disproofs, so all the astronomical answers for the Star are dead. 
In 1999, Michael Molnar put forth a completely new solution, where the Star originated as a report of a natal horoscope for 17 April 6 BC. This natal horoscope shows very impressive regal portents and points to Judea. It is very improbable that such a very rare planet configuration (averaging only once per millennium or longer) would coincide with the very restricted day of Jesus' birth (springtime in a year shortly before Herod's death in 4 BC), unless there is some causal connection. The Magi (as labeled by the gospel author) were astrologers, so they were only interested in horoscopes. The astrological solution is further supported by the presence of an astrological technical term ('in the east' meaning what astronomers call the 'heliacal rise') in the Nativity narrative of Matthew. 
Importantly, Molnar has only identified the Star as originating from a particular natal horoscope, while making no statement about the nature or historicity of any of the other elements of the story in Matthew. So for example, the Magi might be astrologers as idealized by the Greeks of the time, or they might have been non-existent (invented by a latter-day Greek seeking omens for the birth of a great king), and they might have arrived on 17 April 6 BC or months later, and they might or might not have been three in numbers with given names. But for the Star of Bethlehem alone, Molnar's astrological solution is convincing.
Bradley E. Schaefer, "Astronomical and Historical Evaluation of Molnar's Solution for the Star of Bethlehem" (Pre-Print December 19, 2016)

Thursday, December 22, 2016

Punic Place Names in Britain and Ireland

The evidence that Britain, Ireland, Thule and numerous other coastal and island place names in Britain and Ireland are Punic in origin, as explained at length in this blog post and some related blog posts, is surprisingly solid. 

Indeed, there are multiple collections of strong physical and linguistic evidence to support the existence of a long term Punic maritime trade relationship with the British Isles and Punic immigrant community in coastal towns and cities. This continued for about two thousand years from around the time of Bronze Age collapse until several centuries after the collapse of the Western Roman empire.

The Phoenician language and its later, divergent form Punic are extinct Semitic languages that originated in the Near East and were spoken in antiquity across into North Africa and southern Iberia by Phoenician and Carthaginian traders and colonists. Needless to say, an origin for a number of British and Irish names in these languages is an intriguing possibility, and such a linguistic hypothesis does, in fact, have a potential historical context too. A degree of direct contact between the ancient Punic world and pre-Roman Britain has, after all, often been argued for since the sixteenth century on the basis of a small number of Classical sources that seem to point in this direction, and in recent years this notion has gained a degree of additional support from a variety of numismatic, isotopic, and archaeological evidence, as has been discussed in previous posts. . . .
[I]t is interesting to note that a Punic origin has also been tentatively suggested for three major island names in the region as well as a number of more minor island and coastal names, the names in question being Britain, Ireland and Thule. Needless to say, these suggestions are perhaps the most contentious of all those outlined below, not least because Britain and Ireland already have frequently cited Celtic etymologies, in a notable contrast to the more local or regional names covered here, with Britain usually believed to derive from a word meaning 'the people of the forms' or 'the tattooed people', whilst Ireland (Éire) is often considered to mean 'the fat, or fertile, country'. However, as Broderick in particular has pointed out, these etymologies are not, in fact, wholly certain nor universally agreed upon, and neither are they totally without linguistic issues; moreover, it might be wondered how plausible some of the proposed meanings are as specific people-/country-names too (the use of tattooing and body art was not, for example, confined or specific to the Britons, but seems rather to have been fairly widespread in Iron Age Europe). 
In this light, it is intriguing to observe that Phoenician/Punic etymologies are also available for both of these major island-names, giving the ‘tin land’ (pretan, ‘tin’) for Britain (*Pritan-) and the ‘copper island’ (*’i: weriju:, ‘island of copper’) for Éire/Ireland (*Īweryon). 
Another post in the series on the name of the former island of Thanet (it became a peninsula in the Middle Ages) notes that:
If there is therefore a credible linguistic case and possible context for a Punic origin for Thanet, what then of the historical and archaeological context? 
Certainly, there is a small amount of well-known textual evidence that might have some bearing on this, not least the classical references to a Carthaginian explorer named Himilco. Himilco undertook a maritime expedition—with 'hints of colonization'—north from Cadiz and the Pillars of Herakles (Straits of Gibraltar) sometime just after 500 BC or thereabouts, and it is thought that he visited Britain and Ireland as part of this.(9
Similarly, Strabo (Geography, 3.5.11) mentions the important ancient tin trade with the Kassiterides, the 'Tin Islands', which have often been credibly identified with either the Isles of Scilly or Cornwall, and goes on to state that 'in former times it was the Phoenicians alone', from Cadiz, 'who carried on this commerce'.(10)
A map of Carthaginian coins found in Britain also often coincides with the location of putatively Punic place names:

With regard of oxygen isotope analysis of human remains in Britain a third post notes that:
Several key points emerge from the above summary of burial sites producing oxygen isotope evidence indicative of the presence of people from North Africa and southern Iberia in Britain between c. 1100 BC and c. AD 800, three of which are highlighted here by way of a conclusion. 
First and foremost, it is important to note that at least some migrants from these areas appear to have been present in Britain during all periods from the Late Bronze Age onwards. Whilst the presence of people from North Africa in Roman Britain is to a large degree unsurprising, as they are otherwise attested via literary and epigraphic sources, the fact that it can be shown that people from these areas were very probably also present in Bronze Age, Iron Age and early medieval Britain is a point of some considerable interest. 
Second, the proportion of such individuals in each of the cemeteries surveyed is significant. For example, around a fifth of those buried in the Cliffs End prehistoric cemetery have oxygen isotope values probably indicative of such origins, as do around a quarter of those tested from the three early medieval cemeteries in South Wales and the Late Roman cemetery at Winchester, whilst at Roman Gloucester the proportion may be as high as a third
In this context, it is interesting to note that the anthroposcopic/craniometric analysis of two Roman cemeteries at York similarly points towards the presence of a potentially large number of people whose own or family origins lay in North Africa, with 11%–12% of those examined considered very likely to be of 'African descent', and yet others thought to have potential 'mixed' or 'black' ancestry, up to a possible maximum of 38% of the population buried at Trentholme Drive and 51% of the population in the higher-status The Railway cemetery. Of course, the sites and cemeteries surveyed here are likely to be to some extent exceptional, being located either at local capitals or close to the coast, but these results are nonetheless fascinating and certainly imply that some areas of Britain, at least, saw a degree of immigration from North Africa and/or southern Iberia in the early medieval period and before. 
Finally, it is interesting to note that the potential migrants to Britain from North Africa and/or southern Iberia discussed above include men, women and non-adults, implying that contact between Britain and these areas was not solely the preserve of male mercantile or military groups, as has sometimes been assumed. Indeed, in some cases women and non-adults actually form the majority of the migrants identifiable there via oxygen isotope analysis, as is the case at Winchester and in South Wales.
Another piece of evidence in a fourth post, involves an Mediterranean anchor found in Britain. It notes:
a recently-recognised find of a fifth- to mid-second-century BC Mediterranean ship anchor from British coastal waters. Previous posts on this site have discussed the presence of a significant quantity of Greek autonomous coinage of primarily the fourth to second centuries BC in Britain, including Carthaginian/Punic, Ptolemaic, Numidian and Indo-Greek issues. Needless to say, finds of early Mediterranean anchors off the coast of Britain would seem to add further weight to the argument that there was a degree of long-distance maritime contact between Britain and the Mediterranean during the first millennium BC and that some, at least, of the above coins may well be genuinely ancient, pre-Roman losses that were brought to Britain by Mediterranean traders.
Numidia was the successor state to Carthage established following the Second Punic War in the 3rd century BCE.

Grassroots Astronomy In 13th Century Colorado

Most of the ancient Puebloan sites in the American Southwest have architectural features designed to serve as observatories for the movements of the sun during the course of the year, something common to many early agricultural societies. These are generally limited to public spaces and the homes of chiefs and high priests.

But, in the Hovenweep complex of ruins, along the Colorado-Utah border, from about 1166 CE to 1277 CE, a different phenomena was observed. There, ordinary people' homes also has astronomical observation features (e.g. architectural arrangements that light up a special marker on the day of the winter solstice).

Zuni ethnographic reports from the 19th century indicate that ordinary people used these because they didn't trust the Sun priests who kept the official astronomical and calendar records to get it right.

Teofilo at Gambler's House explains his take on this phenomena, although he doesn't have a pat answer.
Did the Chacoans trust their sun priests more than the later people of Hovenweep and Zuni? 
I think they just might have, and this brings me back to another theory I’ve proposed: that the rise of Chaco to a position of regional dominance in the tenth and eleventh centuries AD may have been associated with Chacoan elites’ control of new and ritually important astronomical practices. The astronomical alignments at Chaco appear to be the earliest known ones in at least the northern Southwest, and possibly the Southwest as a whole, and it’s possible that the development (or acquisition) of observation techniques that allowed Chaco’s leaders to demonstrate unprecedented powers of prediction fueled their rise. As long as those powers seemed to hold, they may have been able to keep close control over knowledge of their techniques, or the common people may simply have not thought to question them. 
But Hovenweep, with its apparently more “democratic” distribution of astronomical knowledge, dates to only slightly later than Chaco. So what happened in between?
It’s hard to say, and this is one of the enduring mysteries of Chaco, but this period (roughly the middle decades of the twelfth century) does appear to have been a time of great change throughout the northern Southwest, with the ultimate result being the loss of Chaco’s regional influence, although the canyon itself wasn’t completely abandoned until the whole region was at the end of the thirteenth century. There were some major droughts that occurred during this period, which seem to coincide with some of the cultural changes, so maybe the Chacoan elites’ esoteric calendrical knowledge no longer seemed to have the control over rain and fertility that they had claimed, and people began to trust them less and to try to do their own observations too. Or maybe there was a more general spread of astronomical knowledge that undermined Chaco’s influence even if its power didn’t appear to fail. It’s very hard to tell exactly what happened, but the patterns are intriguing.
Information about the parallel practices in the "Old World" aren't terribly informative, because they took place thousands of years earlier than they did in the New World. Historians had a brief window in which they could interview Zuni Sun priests before cultural change completely wiped away all memory of the old ways, while many of the old ways associate with this kind of solar astronomy were long gone by the time that a meaningful written historical record had emerged in Eurasia. 

Coahomasuchus Chathamensis, A New Dinosaur Species

A new (to humans) dinosaur species was discovered by one of my friends from high school, who also discovered one of the only other examples of a related species in 1999. It has a range that extended, at least, from North Carolina to Texas. The Carnian Age in which they flourished was 237 to 228.4 million years ago.

It looked a bit like a crocodile, although it was not terribly close related. Both were reptiles, and crocodiles are roughly as closely related to them as birds are within the reptiles, but the cladistic commonality ends there.

We describe a new species of the aetosaur Coahomasuchus, C. chathamensis, based on an incomplete, but largely articulated, anterior portion of a skeleton recovered from a quarry in the Upper Triassic Pekin Formation of Chatham County, North Carolina. This is only the second documented occurrence of Coahomasuchus, with the other being the holotype of C. kahleorum Heckert and Lucas, 1999 from the Upper Triassic Colorado City Formation of Texas. Although much of the specimen is the same size as the holotype of C. kahleorum, the dorsal paramedian osteoderms of the North Carolina taxon are considerably (~1.3×) wider than homologous counterparts in C. kahleorum, and the ventral thoracic osteoderms are also rectangular (~1.5× wider than long), rather than square, presumably to accommodate the wider body. This is a rare instance where two articulated specimens of closely related aetosaur species are available for direct comparison of homologous osteoderms. Isolated osteoderms with similar ornamentation from the same locality indicate that C. chathamensis may have been one of the earliest aetosaurs to attain the broad osteoderm proportions (width:length >3.5:1) otherwise known solely from later branching, spinose taxa such as Typothorax. The co-occurrence of Lucasuchus and Coahomasuchus in both North Carolina and Texas supports past correlations indicating an Otischalkian (Carnian) age for these strata and demonstrates that plesiomorphic, non-spinose aetosaur genera were not necessarily endemic to a single basin in North America.
Andrew B. Heckert, et al.,  "A new species of Coahomasuchus(Archosauria, Aetosauria) from the Upper Triassic Pekin Formation, Deep River Basin, North Carolina", 91(1) Journal of Paleontology 162-178 (December 22, 2016).

Wednesday, December 21, 2016

1100 Posts At Dispatches At Turtle Island

This is the 1100th post at this blog.

It has maintained a surprisingly even balance between physics posts (546) and non-physics posts (554).

This month has had more posts than any other month at this blog, although the year is only a little better than par for the course, as the spring and summer months were lean.

Primordial Black Holes Excluded As Dark Matter Candidate

We model the accretion of gas on to a population of massive primordial black holes in the Milky Way, and compare the predicted radio and X-ray emission with observational data. We show that under conservative assumptions on the accretion process, the possibility that O(10)M⊙ primordial black holes can account for all of the dark matter in the Milky Way is excluded at 4σ by a comparison with the VLA radio catalog at 1.4 GHz, and at more than 5σ by a comparison with the NuSTAR X-ray catalog (10 - 40 keV). We also propose a new strategy to identify such a population of primordial black holes with more sensitive future radio and X-ray surveys.
Daniele Gaggero, et al., "Searching for Primordial Black Holes in the radio and X-ray sky" (Pre-Print December 1, 2016).

There has been strong evidence disfavoring primordial black holes (i.e. black holes created at the dawn of the universe, rather than by stellar collapse and accretion of new matter) as a candidate for the main component of dark matter for a long time. This paper really seals the deal.

LHC Measures W Boson Mass

The ATLAS experiment at the Large Hadron Collider has published the first W boson mass measurement at the LHC.

* The Particle Data Group's world average of W boson mass measurements (which does not include any LHC measurements) puts it at 80.385 +/- 0.015 GeV.

* A global electroweak fit suggests that the true value is closer to 80.356 +/- 0.009 GeV.

* Now, the LHC result is 80.370 +/- 0.019 GeV. This value is between the electroweak fit value and the value from prior measurements from LEP and Tevatron.

The differences in the measurements are pretty subtle.

All of the values above are consistent with each other at the two sigma level. All of the measured and fitted values agree to three significant digits (80.4 GeV). Even the square of the values differ by less than 0.1%.

The accuracy of the LHC measurement of the W boson mass, one part per 4,230, makes the W boson mass one of the more precisely measured of the 30 experimentally measured fundamental constants of the laws of nature.

The Thirty Fundamental Constants

The W boson mass is one of the experimentally measured parameters of the Standard Model of Particle physics. In addition there are the masses of other two fundamental bosons (the Z boson and the Higgs boson), the twelve fermion masses (six quark masses, three charged lepton masses and three neutrino mass eigenstates), the four parameters of the three by three CKM matrix, the four parameters of the three by three PMNS matrix, and three dimensionless coupling constants (electromagnetic, weak and strong), for a total of 26 experimentally measured parameters.

While there are 26 independent degrees of freedom in the Standard Model, any particular set of 26 parameters is not unique. There are multiple ways to parameterize the CKM and PMNS matrixes. One could take the Yukawa's of the fundamental fermions with the Higgs field, or could take all the fermion masses at a single energy scale, or could take pole masses for each of them. You could include both the W boson and Z boson masses, or could use just one of them and the weak mixing angle which is a function of their relative sizes. No particular parameterization of these 26 degrees of freedom is really any more fundamental than another. (One recent paper claims that the PMNS matrix can actually be summarized with just three, rather than four, independent parameters.)

Other Standard Model physical parameters can, in principle, at least, be derived from the other constants, although many are, in practice, also measured experimentally. For example, the experimentally measured value of the Higgs vev is 246.2279579 +/- 0.0000010 GeV. Conceptually, this is a function of the SU(2) electroweak force coupling constant g and the W boson mass. In practice, it is determined using precision measurements of muon decays. Similarly, all of the properties of the hadrons including their masses can, in principle, be determined from these fundamental Standard Model constants, although, in practice, the experimental measurements of these quantities are much more precise than any calculation from first principles that it is possible to do at this time.

There are a few other experimentally measured constants that are fundamental in the same way that the Standard Model constants. These include Newton's constant ("G"), the cosmological constant ("lambda"), the speed of light in a vacuum ("c"), and Planck's constant ("h"). These four bring the number of experimentally measured fundamental constants of the fundamental laws of nature to 30.

There are other properties of the universe that can only be described with experimental measurements (e.g. the total number of baryons in the universe, or the age of the universe), but none of the other parameters are fundamental components of a fundamental physical law of nature that have to be measured.

What We Know About The 30 Fundamental Constants

We have, at a minimum, an order of magnitude accuracy measurement of 29 of them. We still do not know the 30th, the value of the CP violating parameter of the PMNS matrix, to any meaningful level of accuracy, although it is more likely non-zero than it is to be zero.

I recapped 26 of the known values, although not always with the most authoritative measurements as of the time I was writing (all except the three neutrino mass eigenstates) in a 2015 post at this blog. I reviewed the measurements of the three neutrino mass eigenstates in another 2015 post at this blog.

What We Don't Know But Suspect About The 30 Fundamental Constants

Most physicists believe, but cannot prove, that many of the 30 fundamental constants can be derived from a smaller set of fundamental constants through functional relationships that are not currently known to science.

They certainly don't look like they are really "independent" of each other. The fermion masses and CKM/PMNS matrix parameters, for example, display a certain order even though a combination of imprecision in measurement and lack of imagination has prevented us from discovering a precise functional relationship between these parameters. There are mass hierarchies, for example, some of which have been described with great precision, such as Koide's rule for the charged leptons.

But, for now, this is an area of active investigation and speculation, and it has little or no practical engineering effects unless it sheds light on new beyond the Standard Model physics, because we will have precision measurements of all 30 of them before any theory to derive them from more fundamental theories gains a consensus in the field.

Monday, December 19, 2016

Did Humans Evolve In Response To A Global Ice Age

Once upon a time, before India knew Asia, when alligators sunned themselves on shores north of the Arctic Circle, a small, timid, dog-like creature tentatively waded into a river. Fifty million years passed. The continents wandered and crashed, and the ocean reconfigured itself.

Now, where there were once Arctic alligators, there was ice. As for the creature who once dipped its toes into the tepid river, it now swam the frigid seas. The intervening age had transformed it into the largest animal in the history of life on Earth. . . . 
Starting about three million years ago, after a long decline from the high-CO2 greenhouse of the dinosaurs, the earth descended into a waxing and waning low-CO2 ice age—one that continues to this day (albeit precariously). In this ongoing ice age, the planet has swung back and forth between more wintry climes when there was a half-mile of ice crushing Boston and sea levels were 400 feet lower—to warm, but brief, interglacials like today, when the ice sheets temporarily retreat to the poles. And back and forth and back and forth and back again, as the northern hemisphere wobbles in and out of the sunshine.
From The Atlantic.

The story in The Atlantic magazine story goes on to explain that this ice age three million years ago caused small whales and the mega sharks that ate them to go extinct. This happened to the small whales because the shallow oceans over coastal shelves that the thrived in were gone and they couldn't store enough food to travel the long distances necessary to find them. Mega sharks and smaller predatory whales died out because their prey did. Large whales survived and grew larger because their size made them unmanageable prey and allowed them to live off their food stores on trips from the Arctic to Hawaii and back.

Beyond the scope of that article is the evolutionary path of primates.

Primates came into their own around the time of that 53 million year old peak warmth period along with other mammals filling ecological niches left open after the dinosaurs went extinct in the wake of the catastrophic impact that hit the Gulf of Mexico about 60 million years ago. Many Asian primates then went extinct around 34 million years ago when India crashed into Asia resulting in climate change in the region that destroyed their jungle habitats. The common ancestor of Monkeys and great apes also arose around this time.

All of species in subtribe HomininaSahelanthropus tchadensisOrrorin tugenensisPan troglodytes and Pan paniscus share a common ancestor who was probably also intermediate behaviorally between modern chimpanzees and modern bonobos.

The low end estimate of the time frame of the most recent common ancestor of chimpanzees and modern humans is 4.5 million years ago, the high end is about 9.0 million years ago, and the better data favors a date of about 8 million years ago.

Some of the genus and species intermediate between genus Homo and primates ancestral to the large primates of today such as Sahelanthropus tchadensis and Orrorin tugenensis date to 6 to 7 million years ago. Genus Ardipithecus, which has transitioning between life in the trees and bipedal locomotion is about 4.4 million years old.

Australopithecus afarensis (Lucy and her kin) to the genus Homo took flourished from ca. 3.7 million to 3 million years ago. While Lucy and some of her kind were quite small, others were arguably as large as medium sized modern humans (the "arguably" comes from uncertainty regarding species identification, not from uncertainty regarding body size of some Australopithecus or Homo species at that time). Footprints in Tanzania from members of the species A. afarensis and possible also from other early archaic species date to 3.66 million years ago. This is right around the time of the global ice age that turned the biggest whales into the largest animals that have ever lived, and caused other aquatic megafauna to go extinct. 

H. naledi arose an estimated 2.5 to 9 million years agoThe earliest reliably dated remains of Homo habilis, the earliest member of the genus Homo, are dated to 2.33 million years ago. There are other early Homo species dating to between 2.5 million and 1.5 million years ago (SN: 10/3/15, p. 6). Homo erectus dates to 2.0-2.1 million years ago in Africa. 

Thus, the transition to bipedalism in human ancestor species arose around the time of a global ice age that probably turned a great deal of previously jungle habitat into loosely forested savannah and grassland areas.

Sunday, December 18, 2016

The Testimony Of The Dog

The Japanese word for dog is rather similar to the Manchurian (Tungistic language family) word for dog, and strongly contrasts with the Chinese word, although both languages use the same Chinese character to describe a dog.

This is anecdotal evidence for including Japanese in a controversial Greater Altaic language family, although the Korean word for a dog seems to be derived from the Chinese, and other Altaic roots aren't a great fit even in this case.

The Homelands Of Modern Asian Languages And Y-DNA Clades

Half a dozen paternal lines that expanded dramatically ca. 4800 BCE to 3000 BCE and now account for 65% of the population of China.  Each of these paternal lines had origins in a distinct archaeological cultures, and each of them correspond fairly closely to one or two modern language families in the region. 
The Neolithic transition, defined as the shift from a hunter-gatherer economy into the one based on agricultural activities, is assumed to have resulted in extensive human population growths. Despite major progress has been made by archaeologists in the use of archaeobotanic data to reconstruct a reliable time frame of Neolithic transition in China, the roles played by Neolithic transition in East Asian demographic history are not yet well understood. This paper offers a perspective on the issues regarding when and how the East Asian population expanded and its consequences. 
Considering diverse genetic evidences, we revealed that, in East Asia, there were at least two population expansion events in the Paleolithic Era and notably, the latter Paleolithic expansion and climate improvement after Last Glacial Maximum (LGM, about 15 ka) might together facilitate the emergence of agriculture. 
In comparison to the Paleolithic expansion, Neolithic expansion had its own characteristics, such as stronger expansion dynamics and sex-specific expansion pattern. According to the Y-chromosome-based tree in our recent studies, we found strong signals of partial paternal lineage expansions during or after the Neolithic transition, for instance, O3a2c1a-F5 (Oα), O3a2c1-F46 (Oβ), O3a1c1-F11 (Oγ), C3a1-F2613 (Cα), Q1a1-M120 (Qα), and O1a1a1-F78 (Oδ), suggesting the influence of a strong bottleneck caused by cultural changes. 
Finally, we discussed the relationship between major East Asian paternal lineages and linguistic families, as well as early archeology cultures, linking the Daxi culture to the modern Hmong-Mien populations, the Liangzhu Culture and/or Songze Culture to modern Austronesian and Daic populations, and Yangshao Culture, Dawenkou Culture and/or Longshan Culture, and Hongshan Culture to modern Sino-Tibetan populations.

  • Shao-Qing Wen, Xin-Zhu Tong, and Hui Li, "
  • Y-chromosome-based genetic pattern in East Asia affected by Neolithic transition" 426 Quaternary International 50-56 (December 28, 2016).

  • Bernard's blog discusses some of the details of the paper. As translated by Google from the French with a few corrections of my own to the translation:
    Certain haplogroups have prospered as well. These are O3-F5, O3-F46, O3-F11, O1-F78, C3-F2613 and Q1-M120. About 65% of the current Chinese descend from one of these six paternal ancestors. The dates of expansion are estimated between 5000 and 6800 years ago. One of the questions that remains is who these six ancestors were. Were they the founders of the first Chinese complex societies? Were these neolithic expansions linked to the expansion of the present languages: Austro-Asiatic, Tai, Sino-Tibetan and Austronesian? For example haplogroup O3-M134 has a majority among the speakers of the Sino-Tibetan language, O2-O3-M95 and M7 are in the majority among speakers of Hmong-Mien languages and Austro-Asiatic, O1-M119 among speakers of the Thai-Kadai languages and Austronesian languages, and N-Tat in Uralic language speakers.

    Ancient DNA studies are still rare. However, one such study showed us that the haplogroup O3-M7 was found in the Daxi culture in the Yang-Tse valley. This haplogroup is characteristic of the Mon-Khmer and Hmong-Mien peoples. The haplogroup O1-M119 was found in the Liangzhu culture that succeeds the Songze culture in the Yang-Tse Delta. This haplogroup is important among the Daic populations and the indigenous people of Taiwan suggesting that these cultures could be the origin of the Austronesian and Daic populations. The haplogroup O3-M122 was found in Longshan culture and is now common in Sino-Tibetan populations. Finally, haplogroup N-M231 is very common in Hongshan culture in the Liao River Valley. It is common today in the populations of northern Eurasia, the Tibeto-Burmese populations and the Chinese populations. These results link the ancient Yangshao, Longshan, Dawenkou and Hongshan cultures to modern Sino-Tibetan populations. However, more ancient DNA results are still needed.
    Some of the key archaeological cultures are localized on the following map:

    Saturday, December 17, 2016

    Archaic Hominin Gender Dimorphism Or Multiple Archaic Species?

    John Hawks points out a potential alternative interpretation of data from a recent fossil footprint study
    eLife has published a paper by Fidelis Masao and colleagues describing new footprint trails from the famous site of Laetoli, Tanzania: “New footprints from Laetoli (Tanzania) provide evidence for marked body size variation in early hominins”.
    The scientific theme of the paper is about body size and dimorphism. The species presumed to have made all the trackways is Australopithecus afarensis, the only species that has so far been reported from fossil remains at Laetoli, although the tracks at 3.66 million years old are a bit more ancient than any of the fossils. This is the same species as the Lucy skeleton, which was found at Hadar, Ethiopia, and the “First Family” series of fossils from Hadar in the locality known as A.L. 333. In 2010, Yohannes Haile-Selassie and colleagues reported a partial skeleton from Woranso-Mille, Ethiopia, some 3.6 million years old, which also seems to represent a large male individual, that stood just under 160 cm tall. Based on a regression of foot size to stature, the new footprint trail in test pit L8 represents an individual that probably stood around 165 cm, with 10 cm or so error either way. 
    Here’s a neat graphic showing stature estimates for early hominins up through early H. erectus:
    Stature estimates for early hominins from Masao et al. 2016
    Figure 12 from Masao et al. 2016. Original caption: "Estimates of predicted stature of fossil hominin individuals by species over time for the interval 4–1 Ma. Solid symbols (or crosses in bold) refer to stature estimates based on actual femur length; open symbols refer to stature estimates based on estimated femur length, in turn based on femur head diameter. For Laetoli and Ileret, stature estimates are based on footprint length (see Materials and methods). For Laetoli, Ileret and Woranso-Mille, the average value and range of predicted stature are shown. Colours are associated to the geographical location of each fossil/ footprint site on the map." 
    That’s a bit complicated but the point is pretty clear. A. afarensis overlaps with H. erectus substantially in stature. If we consider only the tiny Lucy skeleton (the lowest “x” in the figure at less than 110 cm), we get a misleading view of body size in this early hominin species. But at the same time, Lucy and some other specimens of A. afarensis really are quite a lot smaller than any H. erectus specimens. The conclusion made by Masao and colleagues, applying some statistics, is that A. afarensis was more variable and sexually dimorphic than humans and H. erectus
    This idea of higher dimorphism in early hominins has been the subject of pointed debate over the past fifteen years, a debate that has been driven by insufficient fossil data. . . .  
    I think we should also be skeptical about whether these footprints were really produced by A. afarensis. That species already has problems at Hadar and at Woranso-Mille, where some researchers now recognize multiple species are present. At Laetoli, we should probably apply a level of skepticism to the idea that only one fossil species could be present.
    Hawks then goes on to explain how the standards for documenting fossil finds have grown much more rigorous over the last forty years as it has become practical to do better documentation.

    Mixed Results In A Test Of Lepton Universality

    A new experimental result finds a local 2.6 sigma deviation from the Standard Model expectation of charged lepton universality in particular kinds of B meson decays. But, after considering look elsewhere effects, it is consistent with the Standard Model. Thus, it tends to disprove the case for charged lepton non-universality from several over measurements that are individually not that notable, but collectively seem to have significance. But, it doesn't do so very strongly.
    We present a measurement of angular observables and a test of lepton flavor universality in the BK+ decay, where  is either e or μ. The analysis is performed on a data sample corresponding to an integrated luminosity of 711 fb1 containing 772×106 BB¯ pairs, collected at the Υ(4S) resonance with the Belle detector at the asymmetric-energy e+e collider KEKB. The result is consistent with Standard Model (SM) expectations, where the largest discrepancy from a SM prediction is observed in the muon modes with a local significance of 2.6σ.
    Belle Collaboration, "Lepton-Flavor-Dependent Angular Analysis of B→K∗ℓ+ℓ−" (December 15, 2016).

    Other experiments looking for lepton universality violations are reviewed here.

    Mallory's Revised Views On Tocharian Origins

    Months ago, I mentioned that leading Indo-Europeanist Mallory had a meaty new paper on Tocharian origins. But, I didn't dig into his conclusions at the time.

    In essence, he has lost the courage of his convictions in his earlier solution, in part because he has simply become more skeptical, and in part, because he is troubled by the source of cereal growing in the Tocharian culture when there is no archaeological evidence that the predecessor culture he has assigned to the Tocharians midway into their route, engaged in this kind of cereal growing. He expounds on this particular problem in a recent short paper:
    The critical issue for these models is that while any and all of them could explain the distribution of domestic animal names, there are serious problems involved with the spread of arable agriculture. As Anthony remarks in this symposium, there is really no serious evidence for arable agriculture (domestic cereals) east of the Dnieper until after c 2000 BCE (see also Ryabogina & Ivanov 2011; Mallory, in press:a). This means that there is also no evidence for domestic cereals in the Asiatic steppe until the Late Bronze Age (Andronovo etc). From the perspective of the Pontic-Caspian model, the ancestors of the Indo-Iranians and Tokharians should not cross the Ural before c 2000 BCE at the very earliest. Hypotheses linking the Tokharians to earlier eastward steppe expansions associated with the Afanasievo or Okunevo cultures of the Yenisei or Altai (Mallory and Mair 2000) become very difficult if not impossible to sustain (as long as there is no evidence of arable agriculture in these cultures) as Tokharian retains elements of the Indo-European agricultural vocabulary. Of course, it should be emphasized that sites of the Afanasievo and Okunevo cultures are overwhelmingly burials that hardly provide the context in which one expects to recover the remains of domestic cereals; moreover, there is no evidence that any of these sites have been excavated in such a way that the recovery of seeds is likely. On the other hand, domestic cereals have been recovered from the site of Begash in the Jungghar mountains at dates of c 2300 BCE (Frachetti 2012) although this site is not connected (so far as we know) with the steppe trajectory of sites (Afanasievo, Okunevo). 
    If this were not bad enough, it is also difficult to map the agricultural vocabulary across a Pontic-Caspian homeland within Europe itself. Main elements of the scheme suggested by Nikolai Merpert in 1977 still appear to be valid in current models of the evolution of steppe cultures involving an east (Volga-Ural) to west (Dnieper) cultural trajectory but if there was little or no agriculture east of the Dnieper, then how can we describe the eastern archaeological cultures of the Don (Repin), Volga (Khvalynsk) or the entire Don-Ural region (Yamnaya) as Indo-European if they lacked arable agriculture? That the steppe populations exploited wild plants such as Chenopodium and Amaranthus is well known and while this might explain the ambivalence of some of the cereal names to reflect a specific cereal type (rather than just ‘grain’) we would still need to explain why the semantic variance among cognate words is largely confined to ‘wheat’, ‘barley’ and ‘millet’ as if at least one of these was the original referent (and not some wild grain). All of the above problems would also be inherent in Renfrew’s revised version of the Anatolian homeland model that requires the eastern IndoEuropeans (Indo-Iranians, Tokharians) to pass through the Pontic-Caspian steppe. 
    Conversely, the Near Eastern model, that requires the ancestors of the ‘ancient European’ languages to wander through Central Asia, cannot place the ‘Europeans’ north of south Central Asia before c 2000 BCE at the earliest. This is going to render the Indo-Europeanization of Corded Ware horizon that in almost every way imaginable would appear to be archaeologically, spatially and culturally a part of the Indo-European world. More importantly, it creates a ‘bottle-neck’ for the Northwest (?) Indo-European languages dated to about 1500 BCE where they all should have passed from east to west across the Pontic-Caspian and on into Europe. To propose a common secondary home and time depth for Balto-Slavic, Germanic, Celtic and Italic so late leaves hardly any time at all to explain the phylogeny of the European languages and how they arrived in their historical seats. If supporters of this model sought an escape route from the situation they seem to have created for themselves, one might possibly propose the route north through the Caucasus to explain not only Iranians (at Sintashta in Grigoriev’s account) but the rest of the Europeans. However, this is hardly without problems as well as one must also explain how the ancestors of most of the European languages managed to pass through the Caucasus without leaving a trail of European languages. 
    If there are any lessons to be learned, it is that every model of Indo-European origins can be found to reveal serious deficiencies as we increase our scrutiny. One is reminded of Daniel Kahneman’s observation: 
    “It is the consistency of the information that matters for a good story, not its completeness. Indeed, you will often find that knowing little makes it easier to fit everything you know into a coherent pattern” (Kahneman 2011, 87). 
    The problem here, of course, is that over time we have come to know more and more and that our earlier, simpler and more alluring narratives of Indo-European origins and dispersals are all falling victim to our increasing knowledge. We have obviously moved on from the time when Nikolai Merpert first published his analyses of the role of the steppelands within the context of the Indo-European homeland but it is evident that we still have a very long way to go.
    J. P. Mallory, "Twenty-first century clouds over Indo-European homelands" (Conference Presentation in Moscow, September 12, 2012).

    Another major issue which this conference talk discusses is the relationship of the Anatolian languages to the other Indo-European languages.
    Pontic-Caspian. In this model the linguistic ancestors of Anatolian are seen to depart earliest from a homeland north of the Black Sea where they pass through the Balkans (Mallory 1989: 241; Anthony 2007: 259) and, by the beginning of the Bronze Age (depending on which archaeological scenario one wishes to invoke) they enter Anatolia to settle and eventually dominate local non-Indo-European populations such as the Hatti. Later, within the PonticCaspian homeland, Brugmanian or mature Proto-Indo-European develops. Subsequent migrations carry ancestors of most of the European languages into central and northern Europe while ultimately the linguistic ancestors of the Greeks and Indo-Iranians disperse both west and east during the Bronze Age. These later migrations would also include the ancestors of the Phrygians and Armenians, two other language groups that occupied Anatolia but cannot be regarded as ‘Anatolian’ in the linguistic sense. Whatever the archaeological merits of this argument, this homeland does account for the division between Anatolian and the other IndoEuropean languages.  
    Near Eastern. Although the supporters of this theory may differ in detail, they are at pains to provide a model that allows Anatolian to develop independently of the rest of the IndoEuropean languages who can evolve together. For example, in Grigoriev’s model, the ancestors of the Anatolians move from Anatolia into the Balkans while there are subsequent linguistic developments in eastern Anatolia that can account for the shared development of the other IE languages (Grigoriev 2002: 354–357, 412–415). Later, Anatolian relocates back to Anatolia during the Bronze Age while the ancestors of the Greeks (at least some of them) may have made their way through the Caucasus and into the Balkans. Thus this model also meets the minimal requirement of explaining the first element of Indo-European phylogeny, the separation of Anatolian from the rest of Indo-European although the subsequent movements of the other IE languages appear far more complicated than those proposed in the Pontic-Caspian model.  
    Anatolian Neolithic. In Renfrew’s (1999) revised model (Plan B), Anatolian remains within the homeland while the rest of the Indo-European languages disperse into Europe which would again permit Proto-Indo-European to evolve separately from Anatolian and Phrygian and Armenian could later ‘return’ to Anatolia. As for the Asian languages, this model is not significantly different from the Pontic-Caspian model. This model then also provides a possible spatial solution to the initial break-up of Indo-European.  
    On the other hand, the recent hypothesis of Bouckaert et al (2012) deals with the split between Anatolian and the other Indo-European languages in a very different way. It appears to situate the homeland (and Proto-Anatolian) in Anatolia. With Anatolian emerging in the centre, the European Indo-Europeans (ancestors of Greek, Latin, etc) disperse westwards into Europe through the Aegean and Balkans and the Asiatic Indo-Europeans (Indo-Iranians) move eastwards towards the Indus, i.e. there is a symmetrical ‘big bang’ from a homeland identical to the later historical seats of the Anatolian languages. It seems to me that there is no attempt whatsoever to deal with the division between Anatolian and the other Indo-European languages that, according to the authors’ own chronology, arise millennia later. Particularly noticeable is that this model appears to situate the ancestors of Greek in Greece to the west of Proto-Anatolian and the ancestors of Indo-Iranian far to the east of Anatolian thus preventing both branches from sharing the 2500 years of common development that is required by this model’s own chronology and phylogeny. How is one to explain parallel linguistic innovations both to the east and west of the region assigned to proto-Anatolian? The statisticians who devised this model seem to require some form of mutual contact at a distance, one of the stranger aspects of quantum theory that Einstein once dismissed as Spukhaftige Fernwirkung. It is difficult to see how one can resolve this problem without either revising the model so that all the rest of the Indo-European languages are ejected in a single direction from Anatolia or creating a complexity of movements within Anatolia. The first solution is indeed the one that Renfrew adopted in his revision that appears to be contradicted by the Bouckaert model; the second solution is more difficult to imagine as the time depth involved would appear to anchor the model with the spread of agriculture to Greece in the 7th millennium BCE (and hence force the ancestors of the Indo-Iranians into the same process if they must evolve along with the Proto-Greeks?) or disassociate the Greek movements from the Neolithic to a later period (the Bronze Age?) which will still require one to somehow connect their putative development with the Proto-Indo-Iranians. One might try to employ Robert Drews’ (1988) ingenious chariot model with the spread of Greeks and Indo-Iranians set to c 1600 BCE and linked to chariot warfare but this would bring Bouckaert’s entire chronology of the Indo-European languages into total disarray. In short, this is the one model that does not seem to address the only feature of Indo-European phylogeny that has near universal support. 
    There is naturally an alternative view of Anatolian that does not support its relatively great antiquity but rather explains its absence of features found in other IE languages as ‘losses’. As these are generally explained by losses occasioned by the impact of a non-IE substrate on Anatolian within Anatolia itself, this alternative model can hardly support the notion that the Indo-European homeland was within Anatolia.
    I personally feel that the archaeological evidence strongly undermines an origin for the Anatolian languages that is more than a century or two older than Greek or Indo-Iranian, and that a very different non-Indo-European substrate for the Anatolian languages than the substrate of the other Indo-European languages (or almost no substrate at all in the case of Tocharian) is the best explanation. The empirical evidence also supports rather strongly the hypothesis that language drift alone is very modest in the absence of contact with other languages.

    Likewise, I personally think that he is not justified in abandoning the conclusion that the Tarim mummies are early Tocharians, and doubting his original hypothesis that Indo-Iranian influences are late contacts with the Saka. This still requires us to find a source for their cereal technology sometime between the arrival of the Tarim mummies in the Tarim basin, ca. 2000 BCE, and their departure from the proto-Indo-Europeans, realistically sometime between 4000 BCE and 2100 BCE, which a linguistic bias towards an older date, and a cereal technology bias towards a later date. But, this is a far more manageable riddle than the epic questioning of all of his assumptions that he raises in this 2015 paper.

    A long, rapid cross county march of thousands of miles at a more or less constant latitude and climate, across the steppe, by people who can ride horses and have wagons has multiple ample precedents. The Turks and the Mongols did so in the other direction. The Russians reversed the tide. Pioneers in the 19th century in the United States did the same thing. A smaller temporal distance between the Tarim Basin mummies viewed as early Tocharians and the predecessor culture shared by the Celtic and Italic Indo-Europeans who surged into Western Europe and Italy respectively, also makes cultural similarities between the two like "witch hats" and primitive tartan style weaving patterns, much easier to understand.

    Renfrew’s Neolithic Anatolian hypothesis, in contrast, is confounded by the existence of common vocabulary for horses and wagons that weren't invented at the time, by the glacial pace of linguistic change it implies contrary to all empirical data on the subject, by the historically attested predominance of non-Indo-European languages in Anatolia prior to 2000 BCE, and by ancient DNA evidence which strongly supports a steppe origin and demic diffusion model of Indo-European expansion.
    This paper has not only failed to provide a solution to the problem of Tocharian origins—it has even helped undermine the author’s earlier solution (Mallory and Mair 2000). Many of the inadequate solutions to the problem of Tocharian origins probably stem from a tendency to take unacceptable shortcuts in developing arguments (e.g., Tocharians are “Westerners,” the Tarim mummies are “Westerners,” therefore, the Tarim mummies must be Tocharians). The tendency has been, at least to some extent, driven by the sheer lack of archaeological evidence, but this is now being dramatically redressed by archaeologists working in Xinjiang. In tackling the issue anew I have tried to approach the entire problem more systematically by listing the criteria that I believe are required of any archaeological solution to the problem. I briefly revisit these below. To reach a solution, it would be necessary:  
    1. To establish the physical and cultural remains of known historical Tocharian-speaking peoples. It can be seen that at the present we lack the type of Tocharian archaeology that would permit us to discern the historical Tocharians through the veneer of urbanism or Buddhism and the international styles in which these were expressed. This might be resolved, at least to some extent, if we had better knowledge of the formation of the northern oasis towns comparable to what we now have for Yumulak Kum.  
    2. To trace the physical and cultural remains of historical Tocharians retrospectively into the prehistoric period. The key obstruction here is that there does not seem to be a valid way by which we might distinguish between a prehistoric speaker of Iranian and one of Proto-Tocharian. The material culture of the Iron Age cemeteries and the few Bronze Age settlements of the region can all be attributed to the Iranians. This, it should be emphasized, is not an issue of “fact” but rather the paradigm within which we seem to be trapped, i.e., any cultural connection with the north or west appears to be with a region where we expect to find Iranian speakers. The reconstructed lexicon also does not serve us very well in determining any critical differences between the reconstructed culture of the Iranians and Tocharians. To be sure, we could adduce finer levels of cultural comparison. For example, we reconstruct for the Indo-Iranians a sacred drink (soma/haoma) which, if its botanical identification among the Iranians be a guide, was ephedra, which is known from special vessels in the BMAC of Turkmenistan, as well as its ubiquity in the Xiaohe horizon (Parpola 2012a, 250–251). If we applied the use of ephedra as a cultural indicator of the Iranians, we would then have to place them in the Tarim Basin by 2000 BCE, which would further reduce any windows for identifying Proto-Tocharians.  
    3. To trace the ancestors of the “prehistoric Tocharians” to a location outside of Xinjiang. The obvious issue here is that if we cannot identify prehistoric Tocharians within Xinjiang, then it will be impossible to tie them to an external origin. This paper has suggested that we seem to be dealing with one of the following phenomena: 
    a. The prehistoric Tocharians are already well known to us from Iron Age cemeteries such as Chawuhugoukou, and their external origins can be traced, perhaps, to the Eurasian steppe cultures of the Iron Age, where we find similar burial practices. In this way the Tocharians are simply a linguistic group who occupied the Eurasian steppe and maintained their language although they apparently absorbed much of their material culture and behavior from their Iranian neighbors. Although Tremblay’s conclusion that the earliest evidence for Tocharian-Iranian contacts coincides with his “Old Sakan,” this does not necessarily require that these contacts took place exclusively within the Tarim Basin, as these contacts could have occurred further north in the steppelands during the period that Parpola (2012a, 223) assigns to Late Proto-Iranian (1500–1000 BCE), which should coincide with the date of early Eastern Iranian. 
    The problem with this model is that it implies that the ancestors of the Tocharians were situated somewhere where they avoided contacts with earlier stages of Indo-Iranian and only began their association with this branch later, when the Eastern Iranians had emerged. In short, it does not indicate where the Tocharians might have been before they came into contact with the Saka, so it does not really get us much further toward Tocharian origins. 
    b. The prehistoric Tocharians are already well known to us from Iron Age cemeteries such as Chawuhugoukou. The Tocharians had appeared south of the Tianshan much earlier than the Iron Age but absorbed material culture and behavior from Iranians over the course of the Early Iron Age within Xinjiang, so that by the Iron Age they were indistinguishable from them archaeologically. Any search for Tocharian origins should be rooted in earlier cultures, e.g., Xiaohe, and not those of the Iron Age. In short, just as the historical Tocharians are viewed through an urban Buddhist filter, the Iron Age Tocharians are obscured by an Iranian filter. 
    One of the obvious problems with this model is that it requires us to establish the origin of the Xiaohe horizon, and, while there are a few comparisons that can be made with cultures from the Altai and Minusinsk Basin, the evidence is not really convincing. Moreover, it is also clear that Xiaohe is entangled with the spread of domestic cereals from west to east or, at least, a recipient of such exchanges, and we are still far from establishing the precise route of this dispersal. 
    c. The prehistoric Tocharians are basically unknown to us. They moved into the oases along the Tarim river and are buried under the foundations of the now increasingly modern towns of Xinjiang. In short, we have been looking in the wrong place. 
    The problem with this approach is that we do not expect the urban centers of the northern Tarim to date much earlier than the first centuries BCE, and it seems unlikely that Proto-Tocharian entered the Tarim Basin so late. It seems far more likely that they entered earlier than this and are to be accounted for in hypothesis (a) or (b) above.  
    4. To trace the cultural path of the prehistoric Tocharians back to a geographical source congruent with their position (temporal and spatial) within the Indo-European language family. Without a firm anchor immediately outside the Tarim Basin one can hardly evaluate Tocharian dispersals within the general framework of Indo-European expansions. From an archaeological perspective, there appear to be (at least) three competing models.  
    a. The Eurasian steppe model (Early Bronze Age) that sets the Indo-European homeland in the Pontic-Caspian region and identifies the ancestors of the Tocharians as members of the earliest eastward expansion of steppe pastoralists from the Urals eastwards to the Altai and Yenisei, i.e., the Afanasievo culture (Mallory and Mair 2000; Anthony 2007, 307–311). This model satisfies those who regard Tocharian as a very early departed language, geographically peripheral to the other Indo-European branches, and eliminates the problem of dating contacts between Tocharians and Indo-Iranians to any period earlier than the entry of the Saka into the Tarim Basin. Among its major problems are: 1) it lacks any evidence of the suite of domestic cereals which the ancestors of the Tocharians should have known; 2) while there may be some Afanasievo artifacts associated with the Qiemu’erqieke culture in the Junghhar basin, these are really totally different cultures, so there is no evidence for an Afanasievo migration south through the Junghhar Basin towards the land of the historical Tocharians; 3) the archaeological case for contacts between the Afanasievo and later Okunevo cultures with the Early Bronze Age culture of the Tarim Basin (Xiaohe) is, other than burial posture, generally weak and circumstantial.  
    b. The Eurasian steppe model (Middle/Later Bronze Age) that sets the Indo-European homeland in the Pontic-Caspian region but identifies the ancestors of the Tocharians as a later Bronze Age phenomenon that followed after the Afanasievo culture, e.g., an element of the Andronovo culture or some other later culture (Kleyn’s Fatyanovo> Karasuk; also Kristinsson 2012). This type of solution might satisfy those who prefer to see the ancestors of the Tocharians more closely related to the European languages, and if the Tocharians had adopted the material culture of steppe Iranians, that makes it easier to argue for an immigration of Eurasian steppe populations into the Tarim Basin, since there is abundant evidence for Andronovo and Karasuk material culture in Xinjiang. By the later Bronze Age period one might also believe that the issue of cereal agriculture could be more easily addressed, as there is evidence for cereal agriculture among the Andronovo tribes. Among its major problems are: 1) it sets Tocharian origins in Europe in geographical areas (northern Europe, central Europe, the Balkans, the forest area of Russia) from which we would far more easily derive the ancestors of the various European branches; 2) other than Kleyn’s attempt to tie the material culture of Fatyanovo with Karasuk, there is no archaeological evidence adduced to support such late migrations of Tocharians across the eastern steppe; 3) it generally results in the Tocharians occupying an archaeological staging area (Andronovo, Karasuk) that we would otherwise naturally assign to the Iranians or some other group. It is true that Andronovo is a higher taxonomic label than “culture” and could well embrace a variety of languages or language groups over its vast area, but, if the Proto-Tocharians were an element of the Andronovo cultural historical region (Kristinsson 2012), we will need to explain why they borrowed vocabulary only from a presumably later sub-branch of Eastern Iranian rather than Indo-Iranian itself. Moreover, we would also need to describe how they came to be absorbed into the Andronovo world and where their place of origin was before this happened.  
    c. The Central Asian model sets the Indo-European homeland anywhere from eastern Anatolia (Gamkrelidze and Ivanov 1995) to Central Asia (Sverchkov 2012 / Сверчков 2012). The potential advantages of this model are that it locates the ancestors of the Tocharians closer to the Tarim Basin and so reduces the length of any migration; it can accommodate cladistics that either place the ancestors of the Tocharians on the periphery (but only if one presumes that the Afanasievo culture is more closely tied with Central Asia than the European steppe), or it can position the Tocharians geographically adjacent to Europeans, who are then presumed to enter Europe from southeast of the Urals. As the earliest wheat in China is identified as bread wheat, the same type as grown in south Central Asia, it provides a more convincing link between China and the West in terms of cereals than does the Eurasian steppe. Among its problems are: 1) it fails to provide convincing evidence that the European steppe cultures (which are integral to this model, which also must explain the spread of the Indo-European languages all over Europe) are derived from east of the Caspian Sea— there are, for example, far more proximate and believable sources for the earliest domestic animals and cereals of the steppe region in the areas adjacent to the European steppe than can be supplied by the Central Asian model (Mallory 2014); 2) the earliest horizon of Central Asian expansions across Central Asia and south Siberia are associated with the Kelteminar culture, which suffers from the same absence of domestic cereals as does the Early Bronze Age Eurasian steppe cultures.  
    d. The combined Steppe and Central Asian model that sets the Indo-European homeland in the Pontic-Caspian but argues that steppe populations intruding into the indigenous agricultural societies of Central Asia adopted many elements of material culture without undergoing language shift. This model is employed, for example, to explain the Indo-Aryans or segments of the Iranians as the hybrids of the Andronovo and the BMAC of Turkmenistan (e.g., Mallory 1998). The advantage of such a model would be that it would allow Eurasian pastoralists to maintain contacts with settled farmers and, presumably, assist them in the retention of the inherited Indo-European vocabulary concerning agriculture and domestic plants. Moreover, it might also provide a “steppe” connection to any model such as Sverchkov’s that derives the Tocharians from Central Asia. This would require the entry of steppe people prior to the Andronovo culture.  
    Evidence for earlier contacts between Eurasian steppe cultures and the settled farmers of south Central Asia is sparse, but it does exist. Afanasievo sherds, for example, have been reported from Gonur Depe in Turkmenistan (Avanesova and Dzhurakulova 2008, 28 / Аванессова и Джуракова 2008, 28) and, more importantly, there are the finds of both Afanasievo (of Yenisei provenance) and Yamnaya remains in a ritual complex at Zhukov, 16 km from Samarkand (Avanesova and Dzhurakulova 2008 / Аванессова и Джуракова 2008), coupled with material compatible with Sarazm II (c 3200–2900 BCE). The complex can be compared with similar Afanasievo cult sites in both the Yenisei and Altai (described in Parzinger 2006, 191, 197). The excavators also see such evidence as adumbrating the Afanasievo-compatible burials of Sarazm IV (c 2300–2000 BCE). No one seems certain precisely how one might link the European steppe, the Zervashan Valley of Tajikistan and the Minusinsk Basin together (mobile traders from the European steppe, a single interaction sphere of exchange relationships, Frachetti’s “Intermountain Corridor”?), but there is clearly evidence in both the Afanasievo and subsequent Okunevo periods for some form of mutual contact. As I indicated above, the reason for suggesting this model is that it places steppe populations in an area where cereal agriculture was well established, so it reduces both the spatial and temporal lacuna between their homes in the Pontic-Caspian region and their possible approach to the Tarim Basin. Unfortunately, the spatial and temporal lacuna with respect to domestic plants now appears not merely between the Urals and the Altai but even farther, between the Dnieper and the Altai (Mallory 2014). I do not know how we are going to be able to resolve these issues, but if we really want to trace the Tocharians to their origins we might paraphrase the immortal lines of ‘Deep Throat’ and “follow the cereals.” 
    J. P. Mallory, “The Problem of Tocharian Origins” Sino-Platonic Papers, 259 (November 2015) at 46-52.