Dr. Robert N. Spengler, Laboratory Director at the Max Planck Institute for the Science of Human History (Max-Planck-Institut für Menschheitsgeschichte), is the author of a book with the intriguing title Fruit from the Sands: The Silk Road Origins of the Foods We Eat (2019). Dr. Spengler is interested in the vast area between China and Europe, which was long thought to be a space for passing through rather than a source of anything significant, and his interest is physical and archeobotanical. His book confirms that this diverse land—arid in some areas and extremely fertile in others—is home to a vast range of crops, from almonds and apples to tea and rice.
You are the author of a book with the intriguing title Fruit from the Sands: The Silk Road Origins of the Foods We Eat (2019). What are the main findings of the book? Can you tell us a bit about how you drew these findings and on what archeological data they are based?
I am happy to answer both parts of that question.
First, I am an archeobotanist or a paleoethnobotanist. I study plant remains from archeological sites, and I have been lucky enough to work in many different areas of Central Asia. I have worked up in more northern regions of Asia, as well into Mongolia and China, and I have been gradually moving southward. Practically speaking, I participate in joint archeological projects that are already established and being run by expert excavation directors. I often work with the material from, say, a hearth or cooking area in an ancient archeological site, or from a trash pit or midden. I analyze the soil sediments and look for plant material, usually seeds. The goal of this research is mostly to determine what people were eating or what plants people used in the past.
I have been fortunate enough to work in Central Asia, which is an area where this method has not traditionally been used. This has allowed my team of researchers and me to answer a lot of really interesting questions, such as what plants traveled along the ancient Silk Road.
The excavated caravansary with the ancient city of Paykend in the background. These trading spots were key hubs in the exchange of plants along the ancient trade routes.
That is the theme of my book Fruit from the Sands: The Silk Road Origins of the Foods We Eat, which covers a wide variety of ancient crops. My goal was to take the reader on a journey through time and also a culinary journey across two continents. As such, the book covers Central Eurasia broadly and spans roughly 5,000 years. It goes back in time before what many people would think of as the Silk Road, but I define the Silk Road very loosely to cover all trans-Eurasian exchange.
The first half of the book, for example, is about the grains, crops, and grasses that shaped the ancient world. I write quite extensively about how the two East Asian or Chinese millets made it to Europe and how wheat and barley from Southwest Asia made it to China in the prehistoric era. I also discuss evidence showing that both crossed through Central Asia and were incorporated into the agricultural system in Central Asia. Later in the book, I elaborate on the fruit crops, which everybody gets very excited about.
Could you share some interesting stories about these familiar grain crops, as well as those fruits, such as the apple, that originated in Central Asia?
I guess the big question that archaeobotanists have been working on with grains in Eurasia relates to the millets. I feel like the field of archaebotany has studied the cereal crops—wheat, barley, and also rice—quite extensively, with an immense amount of research having been conducted over the last 60-70 years. But small grain crops, such as broomcorn millet or foxtail millet, have really only started to spawn exciting new research questions over the last, say, 10 years. And both of the aforementioned millets—broomcorn millet and foxtail millet—were domesticated in northern China but had somehow made it across two continents by approximately 3,500 years ago; they reached Europe and became very important crops in Eastern Europe and, slightly later, in crop-rotation cycles in the Roman and Persian Empires.
These are drought-tolerant, short-season crops, so they eventually became very important to feeding the large empires of the Iron Age and onward that formed across two continents, including across Central Asia proper. The millets also became very important in low-investment agricultural systems in Central Asia, notably as a complement to mobile pastoral economies. In the steppe or Central Asian grasslands, millets eventually became a very important crop in places where wheat or barley might have had a harder time growing.
And the history of fruits—something in which I am very interested—has Central Asia as one of its centers of domestication. The region is often thought of merely as a part of the world that things passed through: the typical idea of the Silk Road is that things that originated in China traveled along it to Europe, while things that originated in Southwest Asia got into China. But there is this whole area in the middle that nobody thinks about. One of the things that my team and I are working on is figuring out which actual plants or important crops in the world today originated in Central Asia. And I think the poster child for this—the crop we talk about most in the book—is the apple.
I think many people now realize that the main part of the genetic material of the modern apple originated in southeastern Kazakhstan in a wild apple forest not far from the modern city of Almaty. So it is a really exciting topic because it was a very important component of the economy of the ancient world, it is one of the most important fruit crops grown in the world today, and it largely originated in Central Asia. There are, of course, some caveats. First, there is very good reason to believe that the wild apple forests covered a much larger area of Central Asia in prehistory, possibly all the way down through Uzbekistan and into the Pamir Mountains, whereas now the population is restricted to this one pocket in Kazakhstan. Second, the domestication did not just happen in Central Asia. Thus, we can say that the apple originates in Central Asia, but it was really domesticated via the Silk Road.
Not only did the apple originate in Central Asia, but it was domesticated via the Silk Road.
When people in early history started moving apples, they inadvertently caused hybridization. There was another wild apple relative in the Caucasus, and when the wild Tian Shan apples from Kazakhstan were planted in the Caucasus, the bees kind of did the rest of the work for the domestication process: they took pollen from the wild apples in one region and combined it with the flowers of wild apples from the other region and created a hybrid. The same process happened again when the apple arrived in Europe, with the result that it hybridized with the European wild apple. So the process is very complicated, but in many ways, not only did the apple originate in Central Asia, but it was domesticated via the Silk Road. Simply by moving it, people completely changed the genetic material. I should also say that the only reason that farmers were able to grow different apple cultivars in the ancient world was because they were able to graft and clone these special hybrids, kind of locking the genetic hybrids into place. It is a very interesting process, but the apple is actually just one of these tree crops from Central Asia.
Another important plant in the world today that was, at least in part, domesticated in Central Asia is the walnut, the wild range of which actually spans from the Caucasus through the Pamir Mountains and across Central Asia. Southern Central Asia is also part of the range for the wild almond.
Yet another really important tree crop from this region is the pistachio, which has its entire wild range in southern Central Asia. I have a graduate student working in my lab right now, Basira Mir-Makhamad from Kyrgyzstan, who is exploring the question of the pistachio as part of her dissertation, so I think we will soon have some better answers as to what the process of pistachio domestication looked like, but we can pretty clearly say that it is another one of these crops that originated in Central Asia and became a major world commodity. The wild range for the pistachio extends south to the northern tip of Afghanistan and touches the edge of the Tian Shan—not quite into Kazakhstan—but all the way down through the mountain ranges, it grows in the foothills, like the apple and walnuts, actually. So the ancient fruit and nut forests that used to cover the foothills of the Central Asian mountains are actually very important to ancient and modern economies.
One of the artifacts we are trying to find in the field is ancient apple seeds. We have found a lot from the Middle Ages, but it is quite surprising how few there are from earlier periods. One of the objectives we are hoping to achieve is to get more projects going in southern Kazakhstan to try to find the ancient apples.
It is believed that the nomadic diet was more protein-based than plant-based. Yet there are many herbs in the steppes that were probably used as food. Could you tell us a bit about the herbs of the region? Have you studied their nutritional or medicinal properties?
This is a complicated question. When I started working in Central Asia while conducting research for my dissertation, it was exactly the question I was interested in: Which wild plants did mobile pastoral populations—or, as you call them, “the nomads”—eat in prehistory? Then I started doing archaeobotanical work and in almost all the sites where I worked, I found lots of evidence for agriculture. It was originally kind of a big surprise, but now we just expect to find agricultural remains everywhere in Central Asia. So the big revelation that came out of the introduction of archaeobotanical methods to Central Asia is that not everybody was a nomad and over time the nomads may not have been the major players in Central Asia. This is kind of a surprise to many people, especially those doing research in Kazakhstan, where mobile pastoralism is such an important part of the economy today and was historically, but the large burial mounds—say, for example, the Issyk Golden Man—likely contain the remains of people who were integrated into an agropastoral system. I mean, in the case of the famous Issyk Golden Man, the bones of the individual no longer exist and cannot be tested to determine his/her ancient diet, but my colleagues who do isotope work on ancient bones have looked at the remains from many other burial mounds and found good evidence showing that the people in these burials ate a lot of grain, especially millet, and the archaeobotanical evidence shows not only millet, but wheat and barley as well. While there definitely were what we would traditionally think of as nomads at various times and in various parts of Central Asia, much of the population over time, especially before the Turkic expansion, was agropastoral. I think part of the issue is that the Turkic advances from Genghis Khan through the Timurid period left an image of a quasi-warrior nomad that has come to dominate both the academic and popular narratives and pervaded all of our discussions. In reality, however, the foothills—for example, along the Tian Shan down through the Dzunghar, Pamirs, and Hindu Kush—were great agricultural lands. In the river valleys, through Ferghana and along the Ili, there was probably a lot of agriculture being practiced at certain times in the past.
That said, as you point out in the question, even the most mobile pastoral groups were still likely using wild plant resources. We do not find a lot of evidence for their use archaeobotanically, but we can still assume that this occurred based on ethnographic analogies. So in the mountain zones highly pastoral groups would historically have dug up wild roots, such as lily bulbs, that would have been an important food source; further north, there are a lot of berries, such as cloudberries or Rubus, that are very important. And there are a large number of different species of leafy greens that may have been important in the past. But again, archaeobotanically, these are slightly harder topics for us to explore.
It is also worth pointing out that there has been a little more work on some of the earlier time periods. So one of the things that we are very much hoping to get at is a better understanding of what cuisines looked like along the Silk Road during the later periods, such as the Qarikhanid period. We are also expanding further back into time with our research and looking at early Holocene diets in Central Asia. Thus far, there is only a little evidence, but even those limited data suggest that these fruits and nut forests were very important to the diet. That is, even before agriculture or pastoralism moved into the region, people were still utilizing some of these plants.
How did the ancient people of Central Asia develop farming techniques in rather arid regions? Did they innovate or borrow from other regions?
Again, this is an interesting and complicated question. Many of my colleagues and I have worked very hard to depict prehistoric Central Asia as more than just an area where everything passed through. This is the traditional image of the Silk Road because the historians who wrote the narrative were either sinologists working in China or Classicists working in the Mediterranean. Traditionally, very few scholars studied Silk Road trade in Central Asia proper, although this situation has changed. In truth, a lot of innovation and technological advancement has come out of Central Asia proper, especially in the medieval periods or the Golden Age of Islam in that part of the world. To this day, we can go to Samarkand and see Timur’s capital centers with their madrasas, big schools that were major places of science and innovation.
Even further back in time, major technological advances in irrigation practices were underway in Central Asia. That said, we know that some of these domesticated crops originated in other parts of the world, as I mentioned above in the case of the millets, which originated in East Asia, and wheat and barley, which originated in Southwest Asia. But what is really important here is that these two East Asian and Southwest Asian crops came together in the same agricultural fields for the first time in Central Asia. Right now, the earliest archeological site to have both sets of crops is in the foothills of Central Asia. So it is clear that while some agricultural technologies spread into Central Asia, the way they were used was very much Central Asian. And what is really amazing about this is that the mingling of East Asian and Southwest Asian crops eventually created the crop-rotation cycles that proved necessary to feed the large empires that formed across the ancient world.
Thus, in many ways, the Roman Empire or the Han Dynasty in China could not have formed without the mingling of these very different crops into a complex agricultural system, and that complex agricultural system originated in Central Asia, allowing all the major empires of the ancient world to feed their dense populations in these growing cities. Technology did spread into Central Asia, but there was also a lot of innovation that occurred in Central Asia proper.
Central Asia is trying to increase its agricultural exports, but so far these are limited to plain grains rather than a wide variety of crops. Do you have any ideas for what Central Asia agriculturists could focus on? Many foreigners note that the fruits of the region are unusually sweet—is this because they are a special variety or just because they are organic?
I am very happy to answer that question, but let me caveat my comments by saying that I am not an agronomist, so this is not actually my area of study, even if I have strong opinions about how some of the Central Asian countries could think about moving forward. The first thing I would say, which is actually already being implemented in the southern Central Asian countries, is that they need to massively reduce cotton cultivation. Cotton is a very water-intensive crop, and it is grown in some of the most arid regions. And I think it is pretty well-known that the decimation of the Aral Sea has largely been tied to the construction of the Karakum canal in the Soviet period. The production of a water-intensive crop in the middle of the Karakum and the Kyzylkum—hyper-arid desert regions—has been a horrible environmental disaster. It has removed an entire sea from the face of the earth, beyond just the water demands. It is also a very pesticide-intensive crop, and that is a complicated situation, but it is tied to the fact that cotton was actually domesticated four times. Cotton has four different centers of domestication, and each one of these centers of domestication came with its own pest load. So there are a lot of bugs that like to eat cotton plants, and that means a lot of toxins need to be sprayed on those fields. Thus, in every way, shape, and form, it is very problematic to cultivate cotton on an industrial scale. Reducing production to a smaller scale is a whole different question, but large-scale industrial production, such as the Soviet Union pushed in Central Asia, is very environmentally destructive and has proven to be one of the negative legacies of the Soviet Union in these Central Asian countries.
For the last five years, I have been working in the Oasis of Bukhara, and when I started working there, in the summer, we would head out there and it would just be cotton as far as you can see. And the last year I was there, which was before the pandemic, almost all the cotton fields had been replaced with fruit and nut trees, crops that have much deeper root systems and are less water-intensive. Even among the more tolerant crops, there are specific fruit and nut trees that have much greater drought tolerance, almonds being one example and pistachios, as a Central Asian domesticate, another. Bringing back some of the ancient crops of Central Asia and replacing industrial-scale cotton production with some of these perennial crops, such as apple, walnut, and pistachio trees, especially the more drought-tolerant varieties, is probably going to be one of the big steps forward, and it is something that is already being implemented in various parts of Central Asia.
You specifically mentioned Central Asian varieties of these, and there are some amazing varieties of fruits and nuts. Some of these are particularly drought-tolerant; for example, Bukhara has a special variety of apricots. The fruit is very small, but it is very drought-tolerant. The fruit is actually very sweet, and the seed inside it lacks the bitter taste, so it is multipurpose. That is one example of a drought-tolerant variety of Central Asian fruit that could be marketed on a much larger scale. There are so many other examples.
Another economic booster that I will just quickly mention is ecotourism. If you are interested in knowing more about ways to boost the economy, Central Asia is the heart of the ancient Silk Road, and it has these amazing mountain forest regions. So rather than expanding water-intensive agricultural systems, which we know are going to be increasingly impacted as global warming continually reduces the glaciers in many of these regions—because glacier melt in the summer is what feeds these agricultural systems, from the Tian Shan all the way down through the Pamirs—it would be valuable to expand tourism. I am talking not just about archeological or historical tourism, but also environmental tourism, because the mountain regions and the arid regions are just so beautiful. But the governments and peoples of Central Asia will need to work together to preserve these great treasures. There is so much that could be done there.
What other interesting archeological findings do you expect in Central Asia? Is it a relatively researched region or can we expect some more news with the advent of newer genetic technologies?
I think that Central Asia, as far as archeology goes, is just coming into its own. During the peak Soviet period of research, there was so much amazing archeological work being conducted there, but in the waning days of the Soviet Union it slowed down or died off. There has been a continual push for new archeology in Central Asia, but due to limited resources the archeological sciences have been overlooked in that part of the world. Central Asia has really exploded onto the international archeological scene in the last 10 years or so as new methods such as archeobotany (my field), but also isotope methods, zooarcheological work with animal bones, and better material analyses methods become available. Geneticists are also moving into this region, studying ancient human and animal genetics. That process is completely changing what we thought we knew about the way people lived in the past and what this part of the world looked like in prehistory.
I think the growing interest in Central Asia is just going to continue. I think we are really just scratching the surface of what the history books and the prehistory books should say about Central Asia. I think there are going to be many major innovations and changes over the next several decades, and I am very excited to be part of that and to be training students and postdocs who will take that tradition forward. Beyond just the plants that my team is interested in, I think we will really learn a lot about human population movements and the way humans interacted with the environment around them in the past. It is all coming together for the first time and I am looking forward to seeing where it goes.
All photos by
Robert N. Spengler