Thursday, December 31, 2020

An Overview Of East Asian and Southeast Asian Historical Linguistics


There are nine main language families in Southeast Asia and East Asia: Japonic (Japanese and a couple of related languages spoken on remote Japanese languages), Korean, Ainu (a language isolate spoken by indigenous people of Northern Japan), Sino-Tibetan (including Chinese, the Tibetan languages and Burmese), Austronesian (also spoken in Polynesia), Thai-Kadai a.k.a. Kra-Dai (of which the language of Thailand is best known), Austroasiatic a.k.a. Mon-Khmer (the most famous of which are Vietnamese and the Munda languages of India and also including the Khmer languages of Cambodia) and Hmong-Mien (a language family of an important minority population in Southeast Asia and South China). 

Genetic and linguistic evidence, however, shows that the Hmong-Mien language family is an offshoot of the Austroasiatic language family. There is strong but not universally accepted evidence that Austroasiatic languages and Thai-Kadai languages are part of a larger macro-language family. There is strong but not universally accepted evidence that the Japonic and Korean languages are part of the same language family.

Sino-Tibetan languages have their roots in the North Chinese millet farming Neolithic revolution on the Yellow River. 

The other four language families have their roots in the Southern Chinese rice farming Neolithic revolution on the Yangtze River. The Austronesian and possibly the Thai-Kadai language families originate in the lower Yangtze River basin. The Austroasiatic, Hmong-Mien and possibly the Thai-Kadai language families originate in the middle Yangtze River basin.

It is likely that none of the major languages of Southeast Asia were spoken there prior to about 2200 BCE. Prior to that point, Southeast Asia was largely populated by Hoabinhian hunter-gatherer populations whose languages are largely lost.

Y-DNA evidence suggests that Austronesian language family speakers are an out group to the other four major Southeast Asian and East Asian language families (Sino-Tibetan, Austroasiatic, Hmong-Mien, Thai-Kadai), with people speaking those languages linked to Austronesians only at a greater time depth.[1] This could be a misleading signal driven by the admixture of Austronesians with Austro-Melanesian populations, however.

The World In 4100 BCE

In 4100 BCE, domesticated rice was not available anywhere in the world except (1) the Yangtze River basin and (2) in the Ganges River basin in India (where it was just a few hundred years old as a domesticated crop). It would be domesticated in South American about a century after that. 

At that time, domesticated millet was not available anywhere in South Asia, Southeast Asia or East Asia except in the Yellow River basin and its near vicinity.

The World In 3100 BCE 

In 3100 BCE, farming was absent, and Paleolithic hunter-gatherers were the sole inhabitants of Japan, Taiwan, mainland Southeast Asia, island Southeast Asia, Papuan New Guinea and the immediately adjacent islands, the Philippines, Australia, and all of South Asia to the east of the Indus river Valley, the now barren Sarasvati river basin and the Ganges river basin. 

None of the languages spoken in Southeast Asia (other than the Papuan languages) or Taiwan or the Philippines today were spoken there. The only language now spoken in in the Japanese islands that existed then was Ainu.

None of the languages now spoken in South Asia or Iran today were spoken there, with the possible exception of the Dravidian languages. The Dravidian languages, if spoken at all, were confined to the small tribes of hunter-gatherers who would adopt farming for the first time in Southern India in the South Indian Neolithic Revolution. 

Oceania from Hawaii and Easter Island to Guam and the Mariana Islands to Fiji and Tonga and the Cook Islands and New Zealand, and also Antarctica, were places where no primate, let alone a modern human, had ever set foot.

In Africa, Bantu expansion had not yet begun, so pretty much all of Africa to the South of the Congo River basin and the jungles of the Congo, and much of East Africa, was inhabited only by hunter-gatherers, and racial and linguistic diversity in Africa was much greater. Likewise, the ethnogenesis of the Berber people had not yet occurred.

In Europe, people with the new predominant Northern European phenotypes (e.g. people with blond hair and blue eyes) did not exist and Indo-European languages were confined to Eastern Europe. The percentage of ancestry of modern Irish people traceable to 3100 BCE is close to negligible as it underwent near total population replacement.

The Ainu Language

The Ainu language is derived from one of the languages of the Jomon hunter-gathers of Japan who inhabited the area from the paleolithic era. It was probably influenced by or related to Paleo-Siberian languages. All of these languages are now nearly moribund.

The Japonic and Korean Languages

The Japanese languages arose when the Yayoi people migrated to Japan from Korea ca. 400 BCE to 300 BCE, derived from the pre-existing language, probably a sister language to Korean, spoken by these people. The deep origins of the Korean language in pre-history aren't well understood.

The Austronesian Languages

The Austronesian expansion from Taiwan began about 3000 BCE, and this expansion of one of the indigenous languages of Formosa is arguably really what defines this language family.[2] The indigenous Formosan languages are probably all derived from the Neolithic Dapenkeng culture that abruptly appeared and quickly spread around the coast of the island around 4000 BCE to 3000 BCE (displacing prior Negrito hunter-gatherer populations), only preceding the migration of one of those cultures to other islands by within the margin of error of available dating methods.[3] The particular archeological culture of mainland South China from which this culture was derived is unresolved, in part because archaeological data from that time period is sparse and undeveloped.[4] 

The Sino-Tibetan Languages
[T]he main ancestry of high-altitude Tibeto-Burman speakers originated from the ancestors of Houli/Yangshao/Longshan ancients in the middle and lower Yellow River basin, consistent with the common North-China origin of Sino-Tibetan language and dispersal pattern of millet farmers.[5]
This conclusion is contrary to many 20th century and early 21st century proposals (putting a homeland in Northeast India or Southern China) but now probably represents conventional wisdom in the field.[5]

So, the Sino-Tibetan languages date the North Chinese Neolithic Revolution which was millet farming and independent in origin from South Chinese and Southeast Asian rice farming. The earliest archaeological culture in this region is the Nanzhuangtou culture which started around 8500 BCE, but it isn't clear that that culture was in linguistic continuity with the cultures that gave rise to the Sino-Tibetan language family. Two major studies in 2019 favor this model but assign a more recent origin to the language family than the first Neolithic culture of the region:
Zhang et al. (2019) performed a computational phylogenetic analysis of 109 Sino-Tibetan languages to suggest a Sino-Tibetan homeland in northern China near the Yellow River basin. The study further suggests that there was an initial major split between the Sinitic languages and the Tibeto-Burman languages approximately 4,200 to 7,800 years ago [2200 BCE to 5800 BCE] (with an average of 5,900 years ago [3900 BCE]), associating this expansion with the Yangshao culture and/or the later Majiayao culture. Sagart et al. (2019) also performed another phylogenetic analysis based on different data and methods to arrive at the same conclusions with respect to the homeland and divergence model, but proposed an earlier root age of approximately 7,200 years ago [5200 BCE], associating its origin with the late Cishan and early Yangshao culture.[6]
The Northern millet farmers and Southern Rice farmers started to integrate into a common culture in which the Han Chinese component eventually became dominant around 3500 BCE.[7]

Other Southeast And East Asian Language Families

Rice was domesticated in Southern China around 7400 BCE.[8] But that doesn't mean that the initial rice domesticating culture was in linguistic continuity with the first Austro-Asiatic populations. And the time depth of the various language of the region is muddy. 
There are two most likely centers of domestication for rice as well as the development of the wetland agriculture technology. 
The first, and most likely, is in the lower Yangtze River, believed to be the homelands of the pre-Austronesians and possibly also the Kra-Dai, and associated with the Kauhuqiao, Hemudu, Majiabang, Songze, Liangzhu, and Maqiao cultures. It is characterized by pre-Austronesian features, including stilt houses, jade carving, and boat technologies. Their diet were also supplemented by acorns, water chestnuts, foxnuts, and pig domestication.

The second is in the middle Yangtze River, believed to be the homelands of the early Hmong-Mien-speakers and associated with the Pengtoushan, Nanmuyuan, Liulinxi, Daxi, Qujialing, and Shijiahe cultures. Both of these regions were heavily populated and had regular trade contacts with each other, as well as with early Austroasiatic speakers to the west, and early Kra-Dai speakers to the south, facilitating the spread of rice cultivation throughout southern China.

By the late Neolithic (3500 to 2500 BC), population in the rice cultivating centers had increased rapidly, centered around the Qujialing-Shijiahe culture and the Liangzhu culture. Liangzhu and Shijiahe declined abruptly in the terminal Neolithic (2500 to 2000 BC). With Shijiahe shrinking in size, and Liangzhu disappearing altogether. This is largely believed to be the result of the southward expansion of the early Sino-Tibetan Longshan culture. ... This period also coincides with the southward movement of rice-farming cultures to the Lingnan and Fujian regions, as well as the southward migrations of the Austronesian, Kra-Dai, and Austroasiatic-speaking peoples to Mainland Southeast Asia and Island Southeast Asia. A genomic study also indicates that at around this time, a global cooling event (the 4.2 k event) led to tropical japonica rice being pushed southwards, as well as the evolution of temperate japonica rice that could grow in more northern latitudes.[7]  
The Tai-Kadai Languages

The Tai-Kadai languages are now most widely spoken in the mainland Southeast Asian country of Thailand, but, this is actually the most recent language family to arrive in Southeast Asia from Southern China.
The high diversity of Kra–Dai languages in Southern China points to the origin of the Kra–Dai language family in Southern China. The Tai branch moved south into Southeast Asia only around 1000 CE.[9]
Genetically, the biggest difference between the Tai-Kadai people within Southeast Asia, and the Austroasiatic populations of Southeast Asia, both of whom have origins in the early Neolithic rice farmers of the Yangtze River basin of Southern China, is that Austroasiatic people, having arrived earlier, have more Hoabinhian hunter-gatherer admixture.[10]

There is strong, but not universally accepted evidence that the Thai-Kadai language family and the Austronesian language family are part of a larger macro-language family.[11]

The Austro-Asiatic and Hmong-Mien Languages

The Austroasiatic language family is probably derived from Southern Chinas Neolithic Rice farmers who trace their culture origins to the domestication of Chinese rice in an independent domestication event. Ancient DNA suggests that this is was the first of the language families of modern Southeast Asia to be spoken there by people who resided there.

The expansion from South China to Southeast Asia took place around 4,000 years ago and close in time to the spread of the Austronesians in Southeast Asia. They displaced Hoabinhian hunter-gatherer populations in Southeast Asia.[12] 

Ancient DNA shows populations genetically similar to modern Austro-Asiatic populations in Vietnam, Laos, and mainland Malaysia by 2200 BCE. [13] But the archaeological record is thin in the relevant time period from the South Chinese Neolithic revolution to 2200 BCE, so dating it is tricky. Still, the oldest ancient DNA may have been from close to the time that the language family arrived there since:
The spread of japonica rice cultivation to Southeast Asia started with the migrations of the Austronesian Dapenkeng culture into Taiwan between 3500 and 2000 BC (5,500 BP to 4,000 BP). The Nanguanli site in Taiwan, dated to ca. 2800 BC, has yielded numerous carbonized remains of both rice and millet in waterlogged conditions, indicating intensive wetland rice cultivation and dryland millet cultivation. A multidisciplinary study using rice genome sequences indicate that tropical japonica rice was pushed southwards from China after a global cooling event (the 4.2k event) that occurred approximately 4,200 years ago.[13] 

A genetically based conclusion that the Hmong-Mien peoples are a comparatively recent offshoot of the Mon-Khmer peoples, something that linguistic analysis has not reached consensus upon, is a finding of considerable importance in parsing out the prehistory of Southeast Asia, even though the hypothesis that Mon-Khmer and Hmong-Mien both belong to a macrolinguistic family (sometimes called Yangtzean) has existed for some time as one of several efforts to link the languages of South China and Southeast Asia into linguistic macrofamilies. An expanded study of Y-DNA population genetics in Southeast Asia by Chinese researchers, confirms that close genetic ties of Mon-Khmer (a.k.a. Austro-Asiatic when the Munda of India are also included) and Hmong-Mien peoples, at least in the patriline, focusing on the O3a3b-M7 Y-DNA haplogroup where the Mon-Khmer appearing at a basal position while Hmong-Mien and Tibeto-Burmese individuals with this hapologroup have subhaplogroups more on the fringes of this patriline tree. O3a3c1-M117, the dominant East Asian haplogroup shows a similar pattern.[1] 


[1] Cai X, et al. "Human Migration through Bottlenecks from Southeast Asia into East Asia during Last Glacial Maximum Revealed by Y Chromosomes." PLoS ONE 6(8): e24282 (2011). doi:10.1371/journal.pone.0024282 

[3] Wikipedia article on History of Taiwan: Early settlement

[6] Wikipedia article on Sino-Tibetan languages: Homeland citing Zhang, Menghan; Yan, Shi; Pan, Wuyun; Jin, Li (2019), "Phylogenetic evidence for Sino-Tibetan origin in northern China in the Late Neolithic", Nature, 569 (7754): 112–115, and Sagart, Laurent; Jacques, Guillaume; Lai, Yunfan; Ryder, Robin; Thouzeau, Valentin; Greenhill, Simon J.; List, Johann-Mattis (2019), "Dated language phylogenies shed light on the history of Sino-Tibetan", Proceedings of the National Academy of Sciences of the United States of America, 116 (21): 10317–10322.

[7] Wikipedia article on Rice: Origins in China

[9] Wikipedia article on Kra-Dai languages

[11] Wikipedia article on Austro-Tai languages.

[13] Wikipedia article on Rice: Southeast Asia

Wednesday, December 30, 2020

Siddi Genetics

People in South Asia with non-trace African ancestry are predominantly part of the Siddi people whose historical origins, primarily during the colonial period, are fairly well documented and are corroborated with population genetic evidence. 

This 2011 paper about the genetics of the Siddi people of South Asia isn't new, but I came across it while looking into something else and it is interesting. The Wikipedia summary at the link above about these people is as follows from the introduction and history sections:

The Siddi (pronounced [sɪd̪d̪i]), also known as Sidi, Siddhi, Sheedi or Habshi, are an ethnic group inhabiting India and Pakistan. Members are descended from the Bantu peoples of Southeast Africa. Some were merchants, sailors, indentured servants, slaves and mercenaries. The Siddi population is currently estimated at around 270,000–350,000 individuals, with Karnataka, Gujarat and Hyderabad in India and Makran and Karachi in Pakistan as the main population centres. Siddis are primarily Muslims, although some are Hindus and others belong to the Catholic Church. . . .
The first Siddis are thought to have arrived in India in 628 AD at the Bharuch port. Several others followed with the first Arab Islamic conquest of the subcontinent in 712 AD. The latter group are believed to have been soldiers with Muhammad bin Qasim's Arab army, and were called Zanjis.

Some Siddis escaped slavery to establish communities in forested areas, and some also established the small Siddi principalities of Janjira State on Janjira Island and Jafarabad State in Kathiawar as early as the twelfth century. A former alternative name of Janjira was Habshan (i.e., land of the Habshis). In the Delhi Sultanate period prior to the rise of the Mughals in India, Jamal-ud-Din Yaqut was a prominent Siddi slave-turned-nobleman who was a close confidant of Razia Sultana (1235–1240 CE). Although this is disputed, he may also have been her lover, but contemporary sources do not indicate that this was necessarily the case.

Siddis were also brought as slaves by the Deccan Sultanates. Several former slaves rose to high ranks in the military and administration, the most prominent of which was Malik Ambar.

Later the Siddi population was added to via Bantu peoples from Southeast Africa that had been brought to the Indian subcontinent as slaves by the Portuguese. Later most of these migrants became Muslim and a small minority became Hindu. The Nizam of Hyderabad also employed African-origin guards and soldiers.
Wikipedia's discussion of the genetics of the Siddi people at the same link mostly tracks this paper (Shah et al. (2011)), and a few other papers that came out close in time to it. Pakistani Siddis have some African ancestry but much less than Siddi people in India.

A Y-chromosome study by Shah et al. (2011) tested Siddi individuals in India for paternal lineages. The authors observed the E1b1a1-M2 haplogroup, which is frequent among Bantu peoples, in about 42% and 34% of Siddis from Karnataka and Gujarat, respectively. Around 14% of Siddis from Karnataka and 35% of Siddis from Gujarat also belonged to the Sub-Saharan B-M60. The remaining Siddis had Indian associated or Near Eastern-linked clades, including haplogroups P, H, R1a-M17, J2 and L-M20.

Thangaraj (2009) observed similar, mainly Bantu-linked paternal affinities amongst the Siddi.

Qamar et al. (2002) analysed Makrani Siddis in Pakistan and found that they instead predominantly carried Indian-associated or Near Eastern-linked haplogroups. R1a1a-M17 (30.30%), J2 (18.18%) and R2 (18.18%) were their most common male lineages. Only around 12% carried Africa-derived clades, which mainly consisted of the archaic haplogroup B-M60, of which they bore the highest frequency of any Pakistani population Underhill et al. (2009) likewise detected a relatively high frequency of R1a1a-M17 (25%) subclade among Makrani Siddis. 

According to an mtDNA study by Shah et al. (2011), the maternal ancestry of the Siddi consists of a mixture of Bantu-associated haplogroups and Indian-associated haplogroups, reflecting substantial female gene flow from neighbouring Indian populations. About 53% of the Siddis from Gujarat and 24% of the Siddis from Karnataka belonged to various Bantu-derived macro-haplogroup L subclades. The latter mainly consisted of L0 and L2a sublineages associated with Bantu women. The remainder possessed Indian-specific subclades of the Eurasian haplogroups M and N, which points to recent admixture with autochthonous Indian groups.

Autosomal DNA

Narang et al. (2011) examined the autosomal DNA of Siddis in India. According to the researchers, about 58% of the Siddis' ancestry is derived from Bantu peoples. The remainder is associated with locals North and Northwest Indian populations, due to recent admixture events.

Similarly, Shah et al. (2011) observed that Siddis in Gujarat derive 66.90%–70.50% of their ancestry from Bantu forebears, while the Siddis in Karnataka possess 64.80%–74.40% such Southeast African ancestry. The remaining autosomal DNA components in the studied Siddi were mainly associated with local South Asian populations. According to the authors, gene flow between the Siddis' Bantu ancestors and local Indian populations was also largely unidirectional. They estimate this admixture episode's time of occurrence at within the past 200 years or eight generations.

However, Guha et al. (2012) observed few genetic differences between the Makrani of Pakistan and adjacent populations. According to the authors, the genome-wide ancestry of the Makrani was essentially the same as that of the neighboring Indo-European speaking Balochi and Dravidian-speaking Brahui.  

From the body text of the paper's introduction and conclusion: 

Siddis, or Habshis, are a unique tribe that has African ancestry and lives in South Asia. They are mainly found in three Indian states—Gujarat, Karnataka, and Andhra Pradesh—and according to the latest census, their total population size is about 0.25 million. The first documented record of Siddis in India dates to 1100 AD, when the Siddis settled in Western India. By the thirteenth century, substantial numbers of Siddis were being imported by the Nawabs and the Sultans of India to serve as soldiers and slaves. The major influx of Siddis occurred during the 17th–19th centuries, when the Portuguese brought them as slaves to India. [Portugal discontinued its African slave trade in 1869.] Previous genetic studies have shown that the Siddis have ancestry from up to three continental groups: Africans, Europeans, and South Asians. . . .
The majority of the Siddis [Y-DNA] haplotypes were found shared on otherwise Bantu-specific branches and were present all over the tree . . . all haplogroup [Y-DNA] B2 Gujarat Siddis formed a cluster and coalesced to their most recent common ancestor 2.4 ± 1 thousand years ago. . . . The effective population size of the African ancestors of Siddis brought to India during the slave trade was estimated as ∼1,400 individuals. 
. . . 
African-specific mtDNA haplogroups were present at high frequency in the Siddis; these results were similar to the observations from the autosomal and paternal lineages. The African-specific haplogroup L was present at a frequency of 53% and 24% in Siddis from Gujarat and Karnataka, respectively. Previous studies have suggested that the L0a, L2a, L3b, and L3e haplogroups are associated with the Bantu expansion. Haplogroup L2a (including L2a1) was observed in the Siddis along with rare sublineages of L2, which further supports the conclusion that the ancestors of the Siddis were most likely African Bantus. The L0d lineage. . . is now largely confined to the Khoisan-speaking South African populations but . . . was possibly more widespread in the past, was also observed in two Siddi individuals from Gujarat state. . . . 
Consistent with the Y-chromosomal results, there is no evidence of African haplogroups in the neighboring Indian populations, thus confirming the hypothesis of unidirectional gene flow to Siddi individuals from contemporary Indian populations. . . . 
During the course of the Bantu expansion, African farmers settled in East Africa. Later, during the 15th to 17th centuries, this region was predominantly ruled by the Portuguese. They brought some Africans to India as slaves and sold them to local Nawabs and Sultans, whose descendants admixed with neighboring populations, comprise the present-day Siddi population of India.

This post was inspired by an article with a mix of accurate facts and a somewhat misleading headline and suggestions. 

Sunday, December 27, 2020

LInear Elamite Allegedly Decoded

The Elamite language of the ancient Elam Empire in what is now Iran, is one of the best known undeciphered languages. A French scholar now claims to have deciphered its script, neck and neck with Sumerian and Ancient Egyptian as the oldest known scripts in the world that are truly proper languages and not just a collection of select symbols. I'll try to confirm the find further as time allows. The report appears to be based upon a conference presentation rather than a peer reviewed journal publication.

François Desset took ten years to decipher linear Elamite and its mysterious symbols inscribed on tablets discovered in 1901.

Writing was desperately seeking reader. Linear elamite, discovered on clay tablets in 1901, has so far remained a mystery. Until the archaeologist François Desset finally deciphers it, after ten years of research. A discovery relayed by Science and the Future . This phonetic script was used in a kingdom that flourished between the 3rd millennium BC and the 2nd millennium BC. It was discovered in 1901, when archaeologists discovered mysterious symbols on vases and several objects buried under the ancient site of Susa, Iran. 4,500 years ago, the country was called Kingdom of Elam, hence their choice to give this name to writing.

From here

What Will Humans Look Like In 100,000 Years

A cute little speculative article imagines what humans might look like 100,000 years from now due to evolution after living in space for a while with a before and after picture.


In 100,000 years

The article motivates its pictures as follows: 

In 2007, artist and researcher Nickolay Lamm partnered with computational geneticist Dr. Alan Kwan and came up with three illustrations. He first hypothesized what we might look like in twenty thousand years, the second in sixty thousand years, and the third 100 thousand years into the future.

According to Lamm, this is “one possible timeline” that takes into consideration both human evolution and advancements in technology and genetic engineering. Lamm and Kwan imagined a possible future where humans would have a much greater ability to control the human genome, and where their living environments might be much different than ours [1].

Here are some of the major changes that could happen, and the reasons why they might occur, according to Kwan and Lamm: 
A larger forehead 

The human forehead has been increasing in size since the fourteenth and fifteenth centuries. According to scientists, when you measure skulls from that time and compare them to our own, people today have less prominent facial features and higher foreheads [2]. It seems logical, then, to imagine a future where our skulls continue to grow to accommodate larger and larger brains. 
Changed Facial Features

Given the advancements we have already made in genetic engineering, Kwan based some of his hypotheses on the assumption that we will be even further ahead sixty thousand years from now. He argued that a greater ability to control the human genome will mean that evolution will have little effect on human facial features. Essentially, our faces will change depending on human preferences- like larger eyes, a straighter nose, and more symmetry between both sides of our faces. 
He also suggested that by then, it is possible that humans will have begun colonizing other planets. People living in places that are further from the sun, and therefore are less bright, may cause their eyes to get bigger to enhance vision. Skin may also be darker to lessen the damage from UV rays outside of earth’s protective atmosphere.
Additionally, he proposed that people will have thicker eyelids, and their frontal bone under their brow will be more pronounced. This will help humans to deal with the disruptive effects of cosmic rays. We already see these effects happening with today’s astronauts.

Kwan says that over the remaining forty thousand years, those features that humans selected for will become even more pronounced. One hundred thousand years from now, it is possible that humans’ eyes, for example, will seem unnervingly large compared to what we are used to today. 
Functional Necessities

Other, smaller changes may be things like larger nostrils. This will allow humans to breathe easier when they’re living on other planets. People may have denser hair to keep their larger heads warm. In an age, however, when you can genetically alter almost any feature about yourself, Kwan suggests that features make us look naturally human will become more favorable.

It is an interesting exercise although it misses some obvious points.

Time Horizons

The notion that this would happen over 100,000 years based upon past experience of the human species is not very credible for the kind of basic visual phenotypes focused upon.

Most of the common phenotypes associated with major "racial" types today evolved much more rapidly. There was no one in Europe who looked like a typical modern Northern European in 4000 BCE. 

Bantu expansion in Africa, in the same time period, caused one West African phenotype to become predominant in most of sub-Saharan Africa, leaving only small relict populations of "Paleo-Africans" like pygmies and Khoi-San people, and subtly reducing the distinctiveness of the typical linguistically Nilo-Saharan East African.

A lot of the distinctiveness of East Asian phenotypes is attributable to the selective sweep of the EDAR gene which is much older than either of the other two examples, but happened, when it did happen, in a matter of a few thousand years, not tens or hundreds of thousands of years.

Genetic engineering, to the extent it occurs, will likewise have its biggest impacts in a matter of a century or two, not thousands of years. And, while the article notes that some geneticists at the time put the prospects of this kind of genetic engineering thousands of years in future, CRISPER technology already available and still in its infancy with lots of room to improve, suggests that this is much less far off than expected in 2007 when it was done, especially for visually striking, but largely cosmetic features that involve only small numbers of genes like eye, hair and skin color, hair texture and curliness, propensity to tan, and freckles.

Genetic engineering will probably start with efforts to actively select against "defects" from Downs' syndrome to bad teeth and vulnerability to specific genetic diseases with simple recessive Mendelian inheritance patterns. Simple cosmetic adjustments that are well understood may follow. And, from there, the chase for enhancements, such as additional cones that allow people to see more colors, may begin. I see those steps taking perhaps a generation or two at a time to progress from one level to the next.

I fully expect the appearance of the average human to be significantly visually different by 3000 CE, not merely tens of thousands of years hence.


Sufficiently far in the future, there will be few, if any, people who are phenotypically comparable to modern Europeans, due to admixture.

The world almost surely will see dramatically more admixture over the next few centuries than it has since the Bronze Age. In this regard Betty Crocker has probably been more predictive in forming a composite, mixed race, customer of the company:

For her 75th anniversary in 1996, a nationwide search found 75 women of diverse backgrounds and ages who embody the characteristics of Betty Crocker. The characteristics that make up the spirit of Betty Crocker are: enjoys cooking and baking; committed to family and friends; resourceful and creative in handling everyday tasks; and involved in her community. A computerized composite of the 75 women, along with the 1986 portrait of Betty, served as inspiration for the painting by internationally known artist John Stuart Ingle. The portrait was unveiled March 19, 1996, in New York City.

Better yet is this National Geographic image:

Selection On Standing Variation

Image from here.

The massive intercontinental admixture we are likely to see also reflects another key point of both natural evolution and selective breeding, which is that most evolutionary selection involves selection within the existing range of variation among people, rather than new mutations that prove beneficial, which are the exception.

Indeed, one of the real challenges in the first wave of genetic engineering will be to avoid the temptation to completely remove genetic diversity, biodiversity and neurodiversity from the human species when it seems to be a net minus in current conditions from the standing range of variation in humans only to discover that these traits may have currently unrecognized benefits sometime long in the future. Otherwise, the demise of human genetic diversity could mirror the mass extinction of species and languages on Earth during the late Holocene. 

Lots of the most important bits, like HLA immunity complexes and temperaments better suited to the world of the far future, are also largely invisible a priori although their functional connection to other traits may make that less true than one would expect as discussed below.

On the other hand, genetic engineering can revolutionize that analysis. For example, if we find a gene that is very valuable in extremely genetically dissimilar octopi that is total absent from vertebrate genetic diversity a few decades from now, we might very well use genetic engineering to make that a common variant in the human genome.


Humans are likely to continue to select for traits associated with domestication of animals, a process that is already well underway.
Darwin observed that domesticated animals share certain traits across species. Domesticates tend to have floppier ears than their wild counterparts, and curlier tails. They're smaller and have recessed jaws and littler teeth. Domestication also shrinks the amygdala, the brain's fear center, leading to a reduction in aggressive, fearful reactions.

Belyaev noticed that his domesticated foxes eventually developed black and white, or piebald, spots, now known to be a classic sign of domestication. Think of the black and white pelts of cows, horses, dogs, and cats – especially those white-footed felines we claim "wear socks."

The thing is, with the exception of docility, these characteristics don't do anything at all.

Research like Belyaev's made it apparent that if you select for friendliness and cooperation in foxes, you get a host of features that come along for the ride that don't serve a purpose – in evolutionary parlance they're non-adaptive, much like the male nipple. Together this suite of traits is called the "domestication syndrome."

For years scientists have recognized that domestication seems to preserve childlike psychological and physical tendencies, especially those that elicit care from parents and other adults. "Cuter" features. A little more helplessness. And friendliness towards humans, supporting Hare's argument. Recent science has helped piece together why this is.

During vertebrate development there is a strip of what are called neural crest cells running down the back of the embryo. As we grow inside the womb, these cells migrate throughout the body to help form the cartilage and bone of our face and jaw, the melanin-producing cells that give our skin pigment, and part of our peripheral nervous system. They also form our adrenal glands, which, among other functions, release cortisol — our "stress hormone" — and adrenaline, involved in our fight or flight response.

Domesticated animals have smaller adrenal glands. Hare believes selection for friendliness results in less neural crest migration, and as a result, less aggressive, reactionary behavior driven by adrenal hormones.

But fewer neural crest cells reaching their intended targets also influences the other traits driven by their voyage through the body, explaining the smaller snouts and jaws seen in domesticates, and white patches of fur lacking melanin. Scientists now know that domestication — whether artificial or natural — seems to involve selection on a gene called BAZ1B, which helps drive neural crest migration during development.
Baby faces are the future. Other related traits, like enhanced childhood language learning relative to adults, may also be the subject to genetic engineering in the future. William's Syndrome illustrates what this might look like, which bears some similarities to mythical elves:

Technology Facilitates Adaptation And Determines What Is Selected For

Technology can also reduce selective pressure on a lot of obvious physical features, like skin color, with things like Vitamin D supplements and sun screen picking up the slack.

Technology can also determine which human traits merit selection.

For example, for most of human history, food supplies with limited and irregular, and there was strong selection for a capacity to survive periods of famine. But in the modern world, selection is likely to focus on an ability to escape the downsides of obesity that present themselves in a more sedentary world where food is abundant and consistently available.

Physically wild movement and hyperactivity may have been beneficial in much of human history, while the future looks likely to reward a capacity to be still and focused.

Some traits may be the subject to genetic engineering, while other forms of non-genetic bioengineering like nutritional supplements, vaccines, and hormone treatments may also play important parts. Nutrition without genetics can prevent common visible consequences of malnutrition and can enhance height. Everyone in the future will probably be more health overall based upon a variety of genetic and non-genetic methods and cultural adaptations to modern technologies that we are struggling with now.

We might end up with genetic engineering that mitigates nearsightedness adapting to a world where reading fine print regularly is essentially, but if laser eye surgery continues to advance, that may not be a priority as other forms of bioengineering will do the trick.

Self-driving cars and other intelligent safety features in mechanical and chemical things may reduce the selective effects that our current society has against people who impulsively drive too recklessly, cross the street without carefully looking both ways, drink and drive, or otherwise engage in conduct that has grown much more deadly for the average persons than it did in the days where land travel was mostly by foot. Likewise, vulnerability to jet lag might be less important in an era of self-driving cars and AI safety features, when grogginess can be deadly, than in one without them.

Intelligence has lots of value in the modern world, but large infant head size also increases the risk of death to mother and child in natural child birth. But this risk may be alleviated in C-sections are universally and widely available, allowing for larger heads and bigger brains (even though average brain size seems to be declining in recent decades).

Another factor that has impeded brain size development is energy drain. The brain uses 20% of the body's energy demand while only 4% of its volume. But if more energy efficient neurons were genetically engineered somehow, that might make it more workable to have larger brains without the metabolic cost faced by prior vertebrates.

At some point, we might want to genetically engineer humans to have natural immunity to lots of diseases, but in the meantime, improved vaccines might make that a low priority.

The interactions of technology and selective pressures make what the future of humanity looks like difficult to predict. A hundred thousand years out, who knows? Maybe we'll look like this:

Buddhist Origins In One Map


Thursday, December 24, 2020

Drought Destroyed River Civilizations In The Turan Before The Mongols Arrived

One emerging repeated pattern in history is that climate destroys a civilization and then, after a civilization is already in its death throes, "barbarians" rush in to fill the vacuum, while famine begets plagues as well. A few of many examples make the point.

It happened in the Indus River Valley Civilization, Mesopotamia, Egypt, the Levant around 2000 BCE that also was pivotal in further Indo-European expansion into Europe. 

There were parallel events of this type in East Asia and Southeast Asia (both island and mainland). 

It happened with Bronze Age collapse in the Mediterranean basin and Europe around 1200 BCE. 

The fall of the Roman Empire was, in part, to due climate issues. 

This happened to the Ancient Puebloans around 1000 CE and related event also pushed Na-Dene peoples out of Canada and into what became the American Southwest severely impacting tribal civilizations with Meso-American roots like the Utes.

Something along these lines facilitated the dramatic Mongol Empire expansion by destroying Central Asian river civilizations (which you'd probably never even heard of) of a region also known as the Turan, clearing the way for barbarian invasions in the late Middle Ages, and that is the subject of a new paper on the subject in PNAS.
While Genghis Khan and Mongol invasion is often blamed for the fall of Central Asia's medieval river civilizations, new research shows it may have been down to climate change. Researchers conducted analysis on the region and found that falling water levels may have led to the fall of civilizations around the Aral Sea Basin, as they depended on the water for irrigation-based farming. . . .

"We found that Central Asia recovered quickly following Arab invasions in the 7th and 8th centuries CE because of favourable wet conditions. But prolonged drought during and following the later Mongol destruction reduced the resilience of local population and prevented the re-establishment of large-scale irrigation-based agriculture."

The research focused on the archaeological sites and irrigation canals of the Otrar oasis, a UNESCO World Heritage site that was once a Silk Road trade hub located at the meeting point of the Syr Darya and Arys rivers in present southern Kazakhstan.

The researchers investigated the region to determine when the irrigation canals were abandoned and studied the past dynamics of the Arys river, whose waters fed the canals. The abandonment of irrigation systems matches a phase of riverbed erosion between the 10th and 14th century CE, that coincided with a dry period with low river flows, rather than corresponding with the Mongol invasion.

Via Science Daily

The paper and its abstract are as follows:

Our paper challenges the long-held view that the fall of Central Asia’s river civilizations was determined by warfare and the destruction of irrigation infrastructure during the Mongol invasion. An integration of radiometric dating of long-term river dynamics in the region with irrigation canal abandonment shows that periods of cultural decline correlate with drier conditions during multicentennial length periods when the North Atlantic Oscillation had mostly positive index values. There is no evidence that large-scale destruction of irrigation systems occurred during the Arab or Mongol invasion specifically. A more nuanced interpretation identifies chronic environmental challenges to floodwater farming over the last two millennia, punctuated by multicentennial-length periods with favorable hydromorphic and hydroclimatological conditions that enabled irrigation agriculturists to flourish.


The Aral Sea basin in Central Asia and its major rivers, the Amu Darya and Syr Darya, were the center of advanced river civilizations, and a principal hub of the Silk Roads over a period of more than 2,000 y. The region’s decline has been traditionally attributed to the devastating Mongol invasion of the early-13th century CE. 
However, the role of changing hydroclimatic conditions on the development of these culturally influential potamic societies has not been the subject of modern geoarchaeological investigations. In this paper we report the findings of an interdisciplinary investigation of archaeological sites and associated irrigation canals of the Otrār oasis, a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage site located at the confluence of the Syr Darya and Arys rivers in southern Kazakhstan. This includes radiometric dating of irrigation canal abandonment and an investigation of Arys river channel dynamics. 
Major phases of fluvial aggradation, between the seventh and early ninth century CE and between 1350 and 1550 CE coincide with economic flourishing of the oasis, facilitated by wet climatic conditions and higher river flows that favored floodwater farming. Periods of abandonment of the irrigation network and cultural decline primarily correlate with fluvial entrenchment during periods of drought, instead of being related to destructive invasions. Therefore, it seems the great rivers of Central Asia were not just static “stage sets” for some of the turning points of world history, but in many instances, inadvertently or directly shaped the final outcomes and legacies of imperial ambitions in the region.
Toonen, W.J.H., et al., "A hydromorphic reevaluation of the forgotten river civilizations of Central Asia." Proceedings of the National Academy of Sciences, (2020) DOI: 10.1073/pnas.2009553117

Wednesday, December 23, 2020

Citation and Quotation Conventions At This Blog

I have added a page regarding my citation and quotation conventions at this blog. It appears in the sidebar.

New Supercluster Discovered

The most familiar kind of structure above the scale of a galaxy is a galaxy cluster. But beyond galaxy clusters are "superclusters" and from there to filaments of the "comic web".

A new Spectrum-Roentgen-Gamma mission (SRG), extended ROentgen Survey with an Imaging Telescope Array (eROSITA) equatorial depth survey (eFEDS) has found a new "supercluster" in its initial calibration runs. It followed up on its findings with radio observations from Low Frequency Array (LOFAR) radio telescope and upgraded Giant Meterwave Radio Telescope (uGMRT) and optical results from the Hyper Suprime-Cam (HSC) confirming the supercluster and helping it to characterize the X-ray, optical and radio properties and its member clusters.
[W]e detect a previously unknown supercluster consisting of a chain of eight galaxy clusters at z=0.36. . . . We further investigate the gas in the bridge region between the cluster members for a potential WHIM  [Warm Hot Intergalactic Medium] detection. . . . We do not find significant differences in the morphological parameters and properties of the intra-cluster medium of the clusters embedded in this large-scale filament compared to eFEDS clusters. We also provide upper limits on the electron number density and mass of the warm-hot intergalactic medium as provided by the eROSITA data. These limits are consistent with previously reported values for the detections in the vicinity of clusters of galaxies. In LOFAR and uGMRT follow-up observations of the northern part of this supercluster we find two new radio relics that are the result of major merger activity in the system. These early results show the potential of eROSITA to probe large-scale structures such as superclusters and the properties of their members. Our forecasts show that we will be able to detect 450 superclusters with 3000 member clusters located in the eROSITA_DE region at the final eROSITA all-sky survey depth, enabling statistical studies of the properties of superclusters and their constituents embedded in the cosmic web.
The introduction to the paper (whose abstract above I have edited as it is rather incomprehensibly written) (most citations omitted) provides context and summarizes the history of supercluster astronomy to date:
Cosmic structures evolve hierarchically from high density peaks in the primordial density field and form galaxies, galaxy groups, and clusters of galaxies under the action of gravity. In the complex large-scale structure formation scenario, these galaxies, groups, and clusters are connected to each other via filamentary structures, called the cosmic web, and form large superclusters. Due to the large crossing times, superclusters are neither virialized nor relaxed, although individual structures located within superclusters, such as galaxy clusters, can be gravitationally bound and virialized. Superclusters contain a variety of structures with a range of masses, from massive and dense clusters of galaxies to low-density bridges, filaments, and sheets of matter, and hence are ideal laboratories in which to study the physical processes that affect the evolution of member galaxies, groups, and clusters. It has been suggested that the supercluster environment strongly influences the evolution of the properties of its constituents. 
For instance, simulations predict that the shape of clusters in superclusters is predominantly elongated, and the elongation is typically along the filament direction. Additionally, comprising a significant amount of baryons in the form of galaxies and diffuse gas, the filaments connecting clusters of galaxies have typical diameters of ∼ few Mpc, and coherence lengths of the order of ∼ 5 Mpc but can extend up to ∼ 20–25 Mpc. Detections of the baryons located in the warm-hot intergalactic medium (WHIM) locked in the filaments could reveal important clues regarding the missing baryon problem in the low-redshift Universe. 

A number of superclusters have been found in deep optical surveys of galaxies. In X-rays, the first flux-limited supercluster catalog was compiled by Chon et al. (2013). Based on the REFLEX II cluster sample, they located 164 superclusters, of which only a couple above redshift of 0.35. Although a number of multiwavelength supercluster catalogs exist in the literature, only a few superclusters and their members have been studied in depth observationally, in particular Shapley supercluster at low redshift, and two high redshift clusters. 

The Shapley supercluster, discovered by Shapley (1930), is one of the most studied superclusters of galaxies in the sky. It is a concentration of more than 20 galaxy clusters in a volume of about 10−3 Gpc3 , and about 20 deg2 in the plane of the sky at a redshift of 0.039. Ettori et al. (2000) combined ROSAT PSPC and BeppoSAX X-ray data to study in detail 3 members of the Shapley supercluster using resolved spatial and spectral analysis. They conclude that A3562, a member of the Shapley supercluster, is not relaxed and has evidence of merging activity. At high redshifts (z > 0.4) the number of known superclusters is extremely small, and even fewer have been investigated in detail. Horner & Donahue (2003) studied the supercluster MS0302 at z = 0.42 composed of 3 massive galaxy clusters. This system was discovered in an X-ray follow up observation using the Einstein X-ray observatory of optically detected cluster members. They measured the X-ray properties, temperature, and luminosity of the members of the system. Recently, Adami et al. (2018) presented the discovery of 35 superclusters found in the 50 deg2 XXL survey (Pierre et al. 2016). Of these clusters, Pompei et al. (2016) studied in detail a supercluster at z = 0.43 consisting of six galaxy clusters. They determined the temperature, luminosity, and total mass of its members, using their internally calibrated weak lensing mass – X-ray temperature scaling relation. From their morphological analysis, they find that 2 of these 6 clusters appear to be disturbed, indicating that they are likely in a merging state. Suzaku observations of A1689 and A1835 investigated correlations between the X-ray properties in cluster outskirts (R500 < R < R200) and their surrounding large scale structure, and found that the outskirts X-ray temperatures in the regions connected to the filamentary structure are higher than those connected to void regions. 

Detailed examination of the connecting bridges of the member clusters of galaxies in superclusters has been an active area of research due to its connection with the missing baryon problem. Detections of the warm-hot intergalactic medium in these regions is quite challenging with current X-ray instrumentation due to the relatively low density (< 10−4 particle cm−3 , corresponding to an over-density of 10-100 times the cosmic value1 ) and low temperature (105 − 107 K) of this gas. Recent dedicated deep X-ray observations suggest the presence of such gas in the interconnecting bridges or filaments between clusters of galaxies, e.g. A3391/95, A222/3, A2744, A1750, and A133. An alternative way to detect this low density gas is through the thermal Sunyaev Zel’dovich (tSZ) effect. Planck Collaboration et al. reported detection of such a gas in the A399-A401 cluster pair with an estimate for the gas temperature of kT = 8 × 107 K and for the electron density of ne = 3.7 × 10−4 cm−3 . It should be noted that these potential detections probe the densest and hottest ends of the WHIM, where the intracluster gas interacts with the colder primordial low-density WHIM gas. Recently, by stacking the Planck Compton y-parameter map of the tSZ signal of galaxy pairs, de Graaff et al. (2019) reported a 2.9σ detection of the WHIM gas with a gas density of ρ = 5.5 ± 2.9 ρb, where ρb is the mean matter density of the Universe, and a gas temperature of kT = (2.7 ± 1.7) ×106 K. Recently, diffuse synchrotron radio emission was detected in the region connecting the pairs A1758N/A1758S and A399/A401 using the LOw Frequency ARray (LOFAR). The origin of the radio synchrotron emission in radio bridges is not well understood, however turbulence generated by the stochastic acceleration of relativistic electrons could be an explanation for the observed diffuse radio emission in A399–A401. 

Statistical multi-wavelength studies of the properties of member structures embedded in superclusters are crucial to develop an understanding of the evolution of the large scale structure. Here we report the discovery of a new supercluster at a redshift of 0.36 in the eROSITA Final Equatorial Depth Survey (eFEDS) performed during the Performance Verification (PV) program. eFEDS is a 140 deg2 field located in an equatorial region, with R.A. from ∼127 to ∼145, and Dec. from ∼-2 to ∼5. It was observed in scanning mode by eROSITA with nominal exposure of about 2.3 ks. In this paper, we examine the X-ray and radio properties of the member clusters of galaxies in their large scale environment and the WHIM gas in the interconnecting region joining the observations from eROSITA in the X-ray, Hyper Suprime-Cam (HSC) in the optical, and LOFAR and uGMRT in the radio band. . . . 
Throughout this paper we assume a concordance ΛCDM cosmology with Ωm = 0.3, ΩΛ = 0.7, and H0 = 70 km s−1 Mpc−1.

1 The critical density of the Universe: ρc = 3H 2 (z) 8πG