The white sticky notes on the office cartons, handwritten or typed in a simple font, cite places such as Masada, City of David, Tel Safi and Ohalo. Each of the cartons, which lie on tall metal shelves, contain paper envelopes and boxes that hold fragments of information and slices of stories – in the form of charred seeds or bits of dried plants – that were discovered in archaeological excavations throughout the Land of Israel. If living seeds are capsules of information that store the genetic knowledge of plants, the seeds found in the digs attest, in addition, to the material and spiritual life of the people who grew, gathered and ate them. The seed survivors – pits of olives that were eaten and thrown away 8,000 years ago, or wheat grains that early inhabitants ate or used to make flour for bread – are no less exciting than the magnificent figurines or vessels unearthed in digs.
“What we’re doing as botanists or as archaeologists is to come to these people’s homes and check their pantry,” says Prof. Ehud Weiss, head of the Archaeological Botany Lab in the Department of Land of Israel Studies and Archaeology at Bar Ilan University. “That home existed 2,000 or 6,000 years ago, but then, as now, our pantry says a lot about who we are. The food we eat reflects our socioeconomic situation and is indicative of the society we live in and relations with the environment. A central question in archaeology is: Who were the people whose cultural remnants we uncover?
“The information archaeological botany provides is fascinating, and relevant for understanding the human race. We are what we eat, and knowledge in our field has become so precise that we now have a high capability of classifying every plant we find in archaeological digs. With the aid of that information, it’s possible to reconstruct modes and customs of nutrition, economy, agriculture, religion and culture.”
Together with archaeologists who specialize in zoology, architecture or ancient art, the lab’s researchers and students take part in digs that bring to light the remnants of the past. “Not everything rots,” Weiss explains. “Some seeds are preserved because of extreme climatic conditions like dryness or cold, and other seeds survive by means of carbonization processes. When Nebuchadnezzar arrived in the Land of Israel, his soldiers burned settlements and houses with all their contents. When walls collapsed and allowed only a little oxygen to enter, a process of carbonization occurred that preserved tree trunks and seeds as they were morphologically. Owing to both climate and a history replete with battles, invasions and conquests, the Land of Israel is a treasure chest of botanical finds from the past.”
Initial selecting, filtering and cleaning of remnants of a plant source are carried out at the archaeological site before continuing in the lab. It is there that the lengthy and exhausting work begins of identifying and classifying the plant remains, and of attempting to infer historical and cultural contexts from the findings.
To facilitate the work of classification, a comprehensive collection of plants from this country and neighboring lands has been created. In contrast to other seed collections, such as the Israel Plant Gene Bank, the lab’s collection contains all the types of plants in the Land of Israel (the Plant Gene Bank is currently focused on wild plants in danger of extinction and on those that are of importance for the human economy), and the goal is not necessarily to preserve them for purposes of future reproduction.
“We have a national collection that includes thousands of seeds and fruits of plants in the Land of Israel and its neighbors,” says Dr. Sue Frumin, manager of the lab. “We do not germinate them or ensure that they retain their vitality; what’s important for us is the morphological form, with the help of which we classify archaeological findings. One of our most important projects in recent years is transforming this vast collection, with its thousands of items, into a digital database. We scan the seeds in three dimensions. Each plant in the collection will have digital representation, and we hope the information will be available to people and researchers from around the world. Because of the diminished variety and the depletion of resources, some of what we have in the collection has become rare and hard to find in nature.”
The lab’s personnel tell riveting stories that shed light on the daily life of the country’s inhabitants in different periods – and on the lives of contemporary scholars who look into the past. “I did my Ph.D. on 23,000-year-old seeds from Ohalo, on the shore of Lake Kinneret,” Weiss says, laughing as he recalls the event. “I found barley grains that were astonishingly preserved, including one seed that started to sprout. Beer is made from germinated barley, and I, as a young doctoral student, thought I would be able to publish an article stating that I had found the world’s most ancient beer. For a whole week, day and night I went through all the barley grains from Ohalo. I turned them every which way, but only that one seed sprouted, apparently by chance. That was a hard week.”
Plants discovered in the Land of Israel in earlier periods, which today are found only in other regions, attest to climate changes and the nomadic routes of edible plants. Seeds of eggplant and shami mulberry, which are integral to today’s local cuisine, were discovered in Jerusalem in Abbasid-era cesspools, revealing the period in which these plants reached the region.
“The grape seeds we found in that dig make a really wild story,” Weiss notes. “The grape is an ancient plant in our region, but we are talking about Muslim Jerusalem, and we found thousands of them, representing six to eight tons of grapes. Did the Jerusalem Muslims actually drink wine, or was this a neighborhood of Jews and Christians? We’re talking about a significant amount, not two grapes that someone ate and spat out the seeds, and because there is hardly any research on the Muslim period it’s very exciting. In general, on the subject of wine we try to map the findings from different periods – almost every dig has grape seeds – and we are participating in a study of the ancient local species of grapes, which differ from the European variety.”
Barley grains found in the Yoram Cave in a cliff of the Masada forttress was the basis for an intriguing study that was recently published in cooperation with eminent geneticists in the field of ancient DNA. “The grains were superbly preserved because of the dryness,” Weiss says. “We took barley grains from there and sequenced them. “Almost 86 percent of the genome was preserved. In the realm of ancient DNA, researchers are delighted sometimes when one percent of the sequence remains. This was the first time a barley genome 6,000 years old was sequenced, and it taught us a great deal.
“We compared it to a world genetic base of barley grains that was made by the German genome bank,” he continues, “and which confirms the hypothesis that the local wild barley was domesticated here and spread worldwide from this country. Potentially, the discoveries make it possible to take positive features from the ancient seeds to help us develop new types of barley and wheat. Archaeologists are perhaps occupied with the past, but always thinking about the future, and the thought that we can wield influence is exciting.”
Along with the collections of ancient seeds and the Land of Israel plant collection – which is kept in vaults behind locked doors – the lab contains findings (which ought to be on display in a museum open to the public) that invoke the fascinating history of botanical research in Israel. On display is a glass case containing stalks from the collection of Aaron Aaronsohn, the agronomist and Zionist activist who discovered wild wheat, or “mother of wheat.” Two years ago the laboratory received from Prof. Mordechai Kislev, founder of archaeological botany in Israel, the collection of the agronomist Ludwig Feiner. In the 1930s, Feiner collected and studied the huge variety of local species of wheat that had not survived. The old stalks, labeled in German in small, dense handwriting, are kept just as Feiner had stored them – in small cardboard and tin boxes that were originally used for cigars, stockings and sweets popular in early 20th century Palestine.