Friday, 17 January 2020

In Memoriam Steven A. Weber

It is with profound sadness that I record the passing away earlier this week of Steve Weber (1954-2020), an archaeobotanist, a friend, a sometimes sparring partner (on issues archaeobotanical), a sometimes co-author, whose ideas and work greatly enriched my own. For most archaeobotanists, he is probably best known for his work on Harappan plant remains, from his book Plants and Harappan Subsistence, to his co-edited volume on Indus Ethnobiology. Although his PhD (Univ. Pennsylvania, 1989) was on the Harappan site of Rojdi in Gujarat, India, he had previously worked in the American Southwest, especially in the Hopi region. After degrees at Northern Arizona State University and attending the first Ethnobiology meeting held in 1978 in Prescott Arizona, he helped to found the Society of Ethnobiology, with Steven Emslie, and edit its Journal of Ethnobiology that launched in 1981 (recounted in his article of 1986). The first issue of that journal partly celebrated the ethnobiological work of the late Al Whiting, which Steve Weber helped to bring to publication as Hasasupai Habitat, which looked in detail on resource use and settlment system of a native group in part of the Grand Canyon region. Steve departed Arizona to take up his PhD work at Pennsylvania and to establiosh the first really large scale machine flotation program of archaeobotany in the Indus valley region at the site of Rojdi with Prof. Gregory Possehl. He later took over the archaeobotany at the excavations at Harappa throughout the 1990s.

He was professor in the Anthropology Department at Washington State University, where he taught from 1994 onwards. On his webpage there, he describes himself as an "archaeologist and archaeobotanist working throughout the world" and working on the themes of "how and why people adopt new subsistence strategies, and how change in subsistence systems relates to change in material culture and settlement systems." He was always quick to point out that he was a field archaeologist first, but he was also a knowledgable and enthusiastic botanist. He certainly did get around-- we had meetings and encounters in France, in London and Cambridge, in the Delhi airport, n Lucknow, in Zhejiang and Kyoto, in San Francisco and Vancouver, Canada, and no doubt others I have forgotten. He was also intently engaging in conversations, full of ideas for further analysis, and extremely generous with his ideas. Sometimes they were quite accidental. We met once in the Delhi airport, both transiting and tired from long flights from abroad, but over coffee we had a conversation about potentially fundamental differences between wheat and barley on the one hand and millets on the other, and whether or not there was something inherent in the productivity of the big-grained cereals that meant they were more likely to support urbanism. Ideas he later developed in his paper "Does size matter?". In this article he suggests that large-seeded crops have larger and deeper root systems, making them much more productive when soils are well-watered in contrast to the more conservative small-grained crops like millets. While one can find exceptions, like northern Chinese urbanism based on millets, there does tend to be higher productivity in the larger grains cereals, allowing for the support of denser populations.

One time we arrived in Lucknow together, and Steve's luggage has been lost, so we spent the afternoon shopping for clothes for him. (He bought quite sensible clothes, while I opted for a rather louder shorts-- see below). Although we were both there for a conference on Lahuradewa and the origins of agriculture, and especially rice agriculture, our conversation strayed, as it often did, the small millets that constitute so much agricultural diversity, not just in India, but around the world. Steve's take was that the great potential of small-scale sustainable millet agriculture was largely overlooked by modern scholarship, in part because of bias towards interest in those large-grained cereals, that were both more easy to find archaeologically and more likely to support urban elites. This resulted in our joint attempt to call attention to millets in worldwide agricultural and archaeobotanical studies, published in Pragdhara 2008.
KS Saraswat, Steve Weber, Dorian Fuller, Mukund Kajale visiting Lahuradewa excavations, Uttar Pradesh, Jan. 2006

Steve Weber and Prof-Yo-Ichiro Sato (Kyoto, summer 2007).
Some of my most lengthy and enjoyable discussions with him took place in Kyoto, where we both had stints as visiting scholars at the Research Institute for Humanity and Nature, and where we were meant to bring order to nearly global archaeobotanical questions of origins and spread of crops being posed by Professor Sato.

Tragically over the pat couple of years he suffered from a degenerative illness. Despite this he was still intent on numerous research issues and ongoing projects when I saw him at a party and conference session in his honor at the SAAs in Vancouver, marked in part by the retrospective on Steve Weber the visionary written with Jade Guedes for the Journal of Ethnobiology. Steven generously passed on his many archaeobotanical samples to Jade, who had joined his department, and so the legacy of his research can be expected to continue to yield results for years to come. 

One of my earlier interactions with Steve was when I had first started teaching in London and I had offered something of a critique to an article on "seeds of urbanism" that he published in Antiquity. And while our published debate might have read somewhat acrominously, he was nothing but supportive and even enthusiastic about discussions with a younger scholar about the finer points of interpretaing patterning in archaeobotanictal data. He insisted that we should distribution together both his original article, my critique and his reply at the South Asia Archaeological conference in Paris in the summer of 2001. He was so focused on moving the field in the positive direction that he took criticism as a positive.  The discussions we began then lead on to many conversations on the value of different archaeobotanical samples based on inferences about how they formed. And he invited me to work with him on our first joint publication  on "formation processes and Palaeoethnobotanical interpretation," perhaps super-ceded by his later critical review on Palaeoethnobotany.  He was humble in his knowledge and a gentleman scholar. His example of putting the pursuit of archaeological knowledge first, before his ego, is an example I will continue to strive for.

He will be sorely missed. Below are some photos I could locate of him. Please do add your own comments thought and memories. I can add more photos if they are emailed to me. 

Steve Weber, Dr. Qashid Mullah, Dorian Fuller, above Kyoto (2007)


Steve Weber at the 2009 conference "Origin of Rice Agriculture and its diffusion to SOutheast and East Asia", Kyoto, August 2009. [from which his publication on rice and millets in Thailand]
Dorian Fuller, Steve Weber, Gao Yu, visiting historic Hangzhou (June 2011)

Steve Weber with Dr Jin Guiyin touring Tianluoshan site, Zhejiang

Visiting Tianluoshan Neolithic site, Zhejiang (Steve Weber at far right). 
Early rice workshop at Peking University, June 2011

Saturday, 20 July 2019

Panicum domestication and early sedentism in Northeast China

For the past decade the Xinglongwa culture of eastern Inner Mongolia (Liao River valley) has been regarded as a likely cultural context for the domestication of common millet (Panicum miliaceum), on the basis of significant quantities of Panicum grains associated with some of the many houses excavated at the site of Xinglonggou (see, e.g. Zhao 2011). Recently, new excavations by a Chinese-Israeli collaborative team (with some London archaeobotanists) explored parts of two new small settlement sites of this period, Jiajiagou (5950-5700 BC) and Tachiyingzi (5550-5450 BC), including intensive flotation, have been published this week in PLOSone. At both sites a single dwelling was excavated and sampled, and the archaeobotanical data indicate a predominance of wild plant foods, including walnuts, apricot endocarps, hawthorns, Phellodendron, but Panicum miliaceum is also present is small quantities-- 16 in total at both sites, with more and higher ubiquity at the later site. Most of these Panicum grains are more elongate then plump, with size and L/W ratios that correspond better to Panicum miliaeceum subsp. ruderale, known today as a weedy species but probably descended from, or at least comparable to the origins wild progenitors. We take this to suggest that grain size/shape was still under going evolution over the course of the 6th millennium BC, and thus it may not have been finished evolving into its domesticated form. This fits the now recurrent pattern of protracted domestication processes in cereals (explored previously when "de-centering the fertile crescent", and demonstrated more statistically in Allaby et al "Geographic mosaics and changing rates of cereal domestication").

These data, along with those from Xinglonggou indicate that while Neolithic sedentism had been established in Northeast China by the early 6th Millennium BC, the evolution of domesticated Panicum miliaceum and the establishment of agricultural economies still took rather longer. Another conclusion of the paper is that sedentism and this domestication process took place during stable and quite conducive climatic conditions. This argues against the hypothesis that domestication in this case was driven by climatic stress, or that it should be linked to major climatic fluctuations that characterize the start of the Holocene (a hypothesis promoted by Bar-Yosef 2011, amongst others)

It is worth noting that the later site (Tachiyingzi) also has the presence of a few Setaria italica and S. viridis, and a couple more plump grains (pictured above). While none of these grains was directly dated there is some possibility that more fully domesticated grains will prove to be intrusive. Amongst the direct AMS dates, on wild foods, four proved to be 6th Millennium BC, but one date on fragments from lotus seeds turned out to be intrusive and late Bronze Age. This highlights the need for more direct dating of crop remains, a point highlighted by recent debates over the arrival of wheat in Late Longshan China, for which numerous false alarms have been dismissed via direct radiocarbon dating (see "Assessing the occurrence and status of wheat in late Neolithic central China: the importance of direct AMS radiocarbon dates from Xiazhai").      

So the case for a millet domestication in Northeast China in strengthened. This does not rule out other dometciation centres-- which there must have been for Setaria italica at least, and perhaps Panicum milieceum. Domestication can be regarded as taking place alongside and after the emergence of sedentism, but further data are needed to better document this, and to assess the extent to which initial cultivation  of wild millet was linked to the shift to sedentism or not. 

Saturday, 13 July 2019

In Memoriam, 'Leo' Aoi Hosoya (1967-2019)

photo by Dorian Fuller
It is with sadness that I report the passing of an archaeobotanical colleague and friend, Leo Aoi Hosoya, who passed on 10 July 2019. Our condolences go first to her family, her husband and daughter. Many archaeobotanists at the IWGP held in Lecce in June 2019 will recall her paper presented in absentia, that began with an amusing video message from Leo. Sadly her health did not improve. "Leo" was actually her adopted English name, based on her zodiac sign, as she had thought that her Japanese name, Aoi, might be difficult to manage for the English. So as Leo she became known to many of us and she played a role in international research not just through her own work (on archaeobotany in Japan and China) but through her place in international networks and networking, facilitated by good humour, friendliness and lack of negativity; she was always contagiously optimistic.

IWGP 1995, Innsbruck: left to right:
Gardar Gu├░mundsson, Mary Anne Murray,
Lydia Zapata, Leonor Pena-Chocarro,
Ann Butler and Leo Hosoya
 [Photo courtesy M.A. Murray]

Aoi was born 14 August 1967. Her global journey could be said to have begun with her post-graduate degrees at Cambridge (from 1992), including her MPhil and PhD. I met her when I started my Master's there in 1995 and we were lab-mates once I started my PhD in 1996. Together with Marco Madella and Victor Paz we formed a group of young researchers interested in various parts of Asia, concerned with rice, millets, etc. and how research approaches that were well-established in Europe, such as analysis of arable weed floras and crop-processing could be translated into new approaches to understanding the Asian past. Leo's work towards her PhD, focused on the Yayoi period in Japan, was very much pioneering, addressing the patterns of crop processing in rice and millets for the first time. She was among the very first archaeobotanist to pull rice spikelet bases out of flotation samples, which we later realized would be essential for studying rice domestication. But her knowledge of Japanese ethnohistorical and archaeobotanical sources also opened my mind to the rich traditions of use and processing of acorns, which very much went on to influence my thinking about nut use in the Neolithic. Her Phd was completed in 2002, but published in a revised monograph-like article in Senri Ethnologica in 2009 [PDF], its title's phrase"Sacred Commonness" reflects her strong interest in relating the mundane of crop processing and agriculture to greater symbolic and social patterns that run through past societies. Her interest in theorizing the social while working through empirical science remains inspiring. Her time as a PhD student in Cambridge brought her to her first International Work Groups for Palaeoethnobotany in 1995 and 1998. (See also the in memoriam of Prof. Martin Jones here).
Leo Hosoya, Dorian Fuller, field trip
during the IWGP 1998, Toulouse, France

For several years, Leo was a post-doctoral research associate at the Research Institute for Humanity and Nature (Chikyukan) in Kyoto. There she was part of the team of a project "Agriculture and Environment Interactions in Eurasia- A 10,000 year history" directed by Prof. Yo-Ichiro Sato, where I was lucky enough to be an invited researcher in 2007 and 2009. She was also part Junzo Uchiyama's Project "NEOMAP", which was looking comparatively on the Neolithic traditions throughout northeastern Asia. Those were optimistic times for international collaborations, new empirical archaeobotanical research and integration across various datasets. For me, Leo was ever a guide to parts of Japan and Japanese archaeology, that I would have otherwise missed. From visits to sites in Hokkaido or Aomori (such as Komakino, below left, or Kiusu, shown at the top), to a memorable trip over the mountains from Kyoto to visit the Torihama shell midden museum to chase down measurable bottlegourds (in 2009; sadly I could find no photos of anything but gourds and woodend tools from that trip- although it resulted in one joint publication on East Asian gourds). It was also a time of many food-centered parties held at the guest house of RIHN.
Leo Hosoya at back left. 

It was at this time that both Leo and I came independently to collaborations with the Zhejiang Institute on the archaeobotany of Tianluoshan, an exciting Neolithic discovery in the Lower Yangtze region made in 2004. Over the years of 2006 and 2007 we made a few tips each to the site to work on sieving and sorting soil samples for plant remains to document the extensive wild food use at the site and the many rice spikelet bases, which lead to recognition of an assemblage in which rice was still undergoing evolution of domestication (another joint publication in Science). This work built on Leo's early efforts both of pulling rice spikelet bases from flotation samples that started in her PhD and of understanding acorn use, which she usefully summarized in this 2011 article.
from Left: Xugao Chen, Ying Zhang, Yunfei Zheng, Dorian Fuller
Ling Qin, Leo Aoi Hosoya, Guoping Sun

While in Kyoto, Leo took a lead roll in organizing some targeted archaeobotanical meetings, bringing together archaeobotanists, geneticists and ethnographic perspectives, first on rice (held in Kyoto in 2009), and later on millets held in Tokyo in 2012. Both lead to special journal issues edited by Leo, on rice, and millets. Subsequent meetings on rice that were held in Beijing and London very much grew out of that first Kyoto meeting. In 2009 she also came to London on a British Academy Darwin researcher's award, and conducted some preliminary work on the processing and detoxification of peach and apricot seeds, plausibly used as nuts or famine foods in Neolithic China (article pdf here).

In subsequent years she became involved in ethnoarchaeological work on rice storage in Bali (2016), which contributed to her ongoing wholistic approach to understanding rice, not just as an agricultural product but as part of social and culinary reorientation of society, as part of what she referred as the "routine-scape" (2014).  Most recently she has been one of the sub-project leaders of a major Japanese-lead international project on "Integrated Studies on Rice-based civilization" for which she has taken a multi-proxy approach to understanding of cooking pots have been used and how this changes over the course of the intensification of rice use in the Lower Yangtze Neolithic an the Yayoi in Japan. She presents some of this work in a chapter published in honour of Martin Jones' retirement, and at the symposium held in Cambridge in Nov. 2018; her chapter "Rice and the Formation of Complex Society in East Asia: Reconstruction of Cooking Through Pot Soot- and Carbon-deposit Pattern Analysis" can be downloaded as part of the book Far from the Hearth (2019). Her in absentia presentation for 2019 IWGP was on the same project, and its holistic approach to an archaeology of cooking is an inspiration for the rest of us to keep working and to enjoy a good meal and a shojiu in Leo's memory.
Please add you own thoughts and recollections using the comment function.

 I can add photos that are  emailed to me.
Rice archaeology symposium, Kyoto, 2009

Leo Hosoya chairing presentations at Rice Symposium

Leo Hosoya (centre) during discussions on the Rice symposium, Kyoto 2009. Prof. Sato (speaking)

Early rice symposium, Peking University, May 2011. Leo Hosoya in front row (second from right)

Early  Rice symposium dinner, from Left: Alison Weisskopf, Heejin Lee, Yuchao Jiang, Michele Wollstonecroft, LEO HOSOYA, Peter Bellwood, Mrs. Bellwood, Mukund Kajale 

The exCambridge Contingent at the International Millets symposium, Tokyo Museum, 2012.
From Left: Victor Paz, Marco Madella, Leo Hosoya, Dorian Fuller, Martin Jones, Xinyi Liu

More photos from the Tokyo meeting (courtesy of Tania Valamoti)

June 2008: Junzo Uchiyama, Leo Hosoya, Oki Makamura (of NEOMAP project)
Pitt-Rivers lab Christmas lunch (1998?), from L: Lila Janik, ?, Martin Jones, Chris Stevems, LEO HOSOYA, Marco Madella,, Hanna Zawadzka, Victor Paz, Dorian Fuller

Pitt RIver laboratory photos ca 1998. Leo Hosoya, seated at right

(Photo courtesy of Tania Valamoti: see appended comment below)


Thursday, 16 May 2019

Thai rice archaeobotanical study win Ben Cullen prize

A recent paper from the UCL Early Rice project has received the  BenCullen prize from Antiquity for 2019 (jointly with other excellent papers). The paper, “Social responses to climate change in Iron Age north-east Thailand: new archaeobotanical evidence” publishe last year, by a co-authorship team lead by Cristina Castillo (UCL), together with Katie Miller (MSc Environmental Archaeology, UCL, 2014), as well as colleagues from Oxford, Charles Higham from New Zealand and Nigel Chang (Australia) has shared this prestigious prize.

The study is based on a long a long regional sequence of archaeobotanical data in northeast Thailand between 3100 BP and 1300 BP from archaeobotanical analyses at Ban Non Wot and Non Ban Jak, both near modern Phimai. In this sequence dry rice weeds decline as wet rice weeds appear around 2100 BP, with an increase in the wet rice and disappearance of dry rice weeds by 1500 BP. This indicates that in the face of increasing aridity rice cultivation was bolstered by irrigation, but it also suggests that increasingly hierarchical societies in the region were investing increasing labour in more intensive, wet rice production. This indicates that wet rice cultivation in the Southeast was a secondary development driven by growth of social complexity, and perhaps population growth, rather than driving the demographic underpinnings of the initial Neolithic in the region. It can also be seen that in this region climatic conditions that made it harder to grow rice based on rainfall lead to cultural techniques that altered the environment to make this crop possible. While rainfed rice has persisted in the hills of Southeast Asia into recent times, throughout most of the plains wet rice cultivation has been the predominant cultivation system which has supported historically known states and urban systems in the region (as aptly described for the past millennium in James Scott's Art of Not Being Governed). The beginnings of these dynamic between wet rice states and hill tribes could have only started form the Iron Age onwards. 

Friday, 21 September 2018

Pearl Millet genomics and domestication centre

Modern genomes have the potential to reveal alot about evolutionary history and past geography of a crop. Of course there are some limitation to the degree that it hard to account for extirpated past populations, such as the wild rice that used to grow in central China or the wild pearl millet that used to grow what is now the Sahara. A new study of pearl millet (Pennisetum glaucum) by Bugarella et al (2018) provides a convincing set of deductions from genetic history that infer an origin of the crop in the western Sahel/Sahara around what is today northern Mali/northeast Mauretania (map at left), followed by early differentiation between those of the far west (Mauretania/Senegal), and the eastern Sahel (e.g. Sudan) from those in the core zones of western Africa. Based on spatial simulations that take into account a few archaeological data points they also estimated the onset of the expansion of pearl millet as crop out of its centre of origin a starting ca. 4800-4900 years ago. This fits nicely with current archaeobotany. The earliest, already domesticated, pearl millet is from northeastern Mali in the lower Tilemsi valley between 2500 and 2000 BC. Perhaps a parallel trajectory of dispersal is represented by the Tichitt Tradition of Mauretania (from ca. 1700 BC). What remains an open question is whether these two area represent distinct domestication trajectories (a point suggested by MacDonald et al 2009; Manning and Fuller 2014), much as we see the West Asian Fertile Crescent as a mosaic of domesticators across the region as more or less the same time ( or there ). The zone delimited by the genetic study could well represent a sort of "West African Fertile Crescent" in which more than cultural groups were in the process of cultivating and domesticating pearl millet during the middle Holocene. The differentiation of a far western genetic groups would then represent dispersal first through the Tichitt-Oualata traditions of Mauretania and onwards to the Sengal valley- which fits with Brunken, De Wet and Harlan's old taxonomic differentiation of a western race leonis (Economic Botany 1977). A rapid and early spread easterns to the eastern Sahel, which was followed by local introgression with local wild populations, is also implied in this genetic analysis, and fits with the albeit limited archaeobotanical evidence for pearl millet (both morphologically domesticated and wild) alongside cultivated sorghum in the Kasala region of eastern Sudan around 1850 BC, just recently published by Beldados et al. (2018)

Ancient DNA in charred grains? More bad news.

No one can have missed the massive impact that ancient DNA has been having on the history of human populations and those of several domesticated animals. Bones, at least some of them, provide a nice venue for the preservation of old genomes. Plants have featured much less in this story, with estimates of 200 C) for sometime (many hours)-- does not do DNA any favours. This who have worked on ancient DNA have tended to focus on desiccated plant remains- from dry desert contexts.

A  new report on ancient DNA extraction from archaeological grains (Lundstrom et al 2018), in this case barley, from Medieval and Late Medieval Sweden, reports some good success from some dry grains from a 17th century's Bishop's burial, some success from waterlogged specimens but no success from 46 charred grains. This replicates similar attempts to get aDNA out of charred Finish barley (Lempaiainen-Avci et al 2018) and methodological trail of Nistelberger et al. 2016 who tried High-Throughput Sequencing ("shotgun sequencing") on various charred archaeological grapes, maize, rice and barley (Pictured at right), including rice provided by my lab from India, Thailand and the Comores. Nistelberger et al. concluded that charred material is likely to rarely yield sufficient reliable genetic data, a conclusion re-iterated by two Scandinavian studies.

The open question is what does this entail for older aDNA results, using "old-fashioned" methods, i.e. targeted PCR, to extract chloroplast DNA, which appears to sometimes be quite successful in differentiating indica from japonica rice for example (Castillo et al 2016), or which was used in the early days of aDNA in the 1990s to separate tetraploid from hexaploid wheats (e.g. Allaby et al 1997). Estimates then were that maybe 5% of charred grains might have some aDNA in them, but maybe those were generous over-estimates? Are we now supposed to reject such earlier work and methods out of hand? Or does it mean that methodologically, there is something about current high-throughput methods that has not solved the problem of dealing with the highly fragmented and sparse DNA that is thought to be preserved in a minority of charred remains? Reading the fine print, Nistelberger did identify a small amount of ancient DNA reads, but they regarded them as so few as to be "inconsequential". But if little is all we are left with maybe we need to change our aims to make these consequential through the questions we ask of them?

Improved methods for looking at plant remains in pots

I have previously highlighted the potential of ct-Scanning and synchrotron imaging to look inside archaeological seeds, or seeds inside archaeological pots. And wanted here to highlight the publication of a more detailed protocol for ct-scanning bits of pottery for looking at inclusions, recently published by Barron and Denham in Journal of Archaeological Science: Reports. We have, of course, been looking at impression of plant temper on the surface of sherds from a long time, since the days of Hans Helbaek in the 1940s. It seems unlikely that the utility of casting  and studying impressions on sherd surfaces will go away, as it remains something that is easily carried out in bulk across large sherd assemblage with relative speed and low cost-- providing among other things our best current evidence on sorghum domestication. Nevertheless, the beauty of ct-scanning lies in the ability to see a much larger sample of impressions below the surface, including those that are potentially much better and more completely preserved than those just on the surface. The example of the rice spikelet pictured at left from a sherd from Loc Giang, a Neolithic site in Vietnam is a nice case in point. 

The spikelet bases from this site and sherds from nearby An Son leave no doubt as the domesticated status of rice in this part of Second Millennium BC Vietnam. Interestingly, imaging also found a wild Lemna (duckweed) seed in a sherd from An Son. What remains an open question, however, from a single specimen like this is whether this should be interpreted as a weed of wet rice, or merely a component of clay gathered from a wetland. The weight of archaeobotanical evidence at present points to Neolithic rice in Southeast Asia being large rainfed (see published discussion in "Pathways of Rice Diversification..."), which would not create conditions suitable for Lemna, so I would favour seeing this as a component of the clay. Also of note is the identification of pebble inclusions in sherds from the hunter-gatherers site Con Co Ngua-- such pebbles are the kind of inclusions that have from time to time been mistaken for seeds in pottery...