What research are you working on during your time at the IIAS?

Currently, I am writing a book on Psalms, a project which developed serendipitously. I became interested in Renaissance psalms translations thanks to my IIAS colleague, Emilie Murphy, who is researching the reception of the psalms in the 17^th century. Together, we discussed the Geneva Bible, an English translation from 1560, written during the Marian exile, and persecution of Protestants. To my mind, it remains one of the best and most precise English translation that exists.

The figure of David focuses his thoughts and emotions frequently through representing the differences between sight and hearing. In Psalms, so much of his experience of founding the People of Israel is based upon hearing. Seeing has a different status, more reflecting the individual fear of God. I've become very interested in both senses in the English translations, and also how these text reflect the original Hebrew text.

Psalms is the most challenging of the books of the Old Testament, because David not only allows for, but cultivates multiple meanings. As a translator, you have to choose one interpretation. The rabbis of the Talmud understand that Psalms provides different angles on the figure of the David, and so many of them are mediated through sight and hearing.

What other projects are you working on?

This year, I finished a book that I started writing over the pandemic, called Literature and the Sacred: God and Reading in a Time of Pandemic. The book is about the way in which Midrash, more particularly midrashic method, has been adapted over the centuries. Although it is a homiletic genre created by the rabbis, in the 17^th century, figures such as Milton and Rembrandt adopted Midrash in their work. For example, Milton's most well-known work, Paradise Lost, is pretty much a Midrash on the Old Testament. Milton knew Pirkei D'Rabbi Eliezer, a Midrashic commentary translated into Latin in 1644. And Rembrandt lived down the block from Menasseh Ben Israel who was a scholar of Midrash – painting his portrait and a frontispiece to one of his theological works. My book focuses on Rembrandt's four paintings of the Samson story, and Milton's 'Samson Agonistes'. I focus on the Midrashic method, rather than the stories, the ways in which Midrash brings past into present.

The project most explicitly related to our group’s work on early modern representation of the senses tells a story that goes from John Milton to Isaac Newton, from the priority of poetry to philosophy. When the authority of Milton and his age ends, there's a movement away from a world based upon time, story, and hearing, into a place of space, experimentation, and seeing. This represents a way of understanding the modern: as we stop telling stories because they are fiction, we become interested in a new kind of truth that we can see and verify with our eyes. The transition from story to sight is really a transition away from the sensibilities of Milton and Rembrandt, in which people would find themselves through reading and writing, through story. There's some tragedy to prioritizing sight, in that we no longer think that reading matters because we are told by scientists that stories don't matter. Not only the stories that we see other people tell, but primarily the stories that we tell ourselves, through which we narrate past, present, and future. In psalms, David is the main storyteller. His contemporaries say to him, "You have no story, and no future. You're done." The Sages say that David invented repentance, because he responds by persisting to write his story. There's a lesson in that for people today. Only through narrative is there a future.

How does your religious background contribute to your academic work?

I think the blessing that I have is that I know how to read into different traditions. Living in the Jewish world, I was constantly exposed to the languages of the Jewish sages. And I internalized them; they are a part of me. I was Haredi and learnt in a kollel [institute for full-time advanced Talmudic study] for 15 years, but the languages of Milton and Shakespeare are in some ways even more important to my self-identity.

I see a responsibility to the people who I teach, because I see that they also want to be part of their traditions, and they want to learn how to read in active creative manners. Great writers who tell stories leave room for your interpretations; they're teaching you how to read, and Milton is the apotheosis of that. Hamlet is the best Midrash on David (don't tell people in my synagogue!) because he's like the 17^th century David. Any emotion – joy, shame, depression, guilt, nihilism – has already been written about by David.

Another thing I realized when I started to study Midrash is that David is behind every conception of individualism that exists in the western world. I teach 17^th century English literature, so I always saw the individual as beginning with Paul, Augustine, and Luther, and continuing with Shakespeare, Christopher Marlowe, and Milton. I always wondered: where is this in the Jewish tradition? I realized that all these figures are reading psalms. It's coming from David. Shakespeare would have heard the whole psalm cycle sung in church every thirty days, and so it was a part of him.  Western and Hebraic traditions are intertwined through David’s Psalms.

How has your time been at the IIAS?

The Institute gives you the luxury to do what you want to do, without being distracted. On the first day, Yitzhak [Hen, the Director of the IIAS] said, "We don’t make any demands: we don't mind what you write, and we're not going to ask you", because he knows that that's how scholars thrive. It’s the exact opposite of every other academic context where nervous administrators are always looking over your shoulder.

Do you know what an incredible place this is? It's scholarly paradise! Academics never have this. I haven't told Yitzhak this yet, but I'm planning on locking myself to this desk at the end of July.

What research are you working on during your time at the IIAS?

My work is divided between editorial work and research. For the editorial part, I am a member of the editorial board of a few international journals, and I'm the Editor-in-Chief of the BioControl academic journal.

For my research, I use theoretical approach to understand insect behaviour. We want to understand what behaviour these insects are using to maximize their reproductive success, so we are using theoretical models to see what is the optimal behavioural strategy used by animals to help maximizing the number of progeny they produce. We build models, use mathematical equations and sometimes complex computations, and then design experiments to see if the insects follow the model’s predictions. Funnily enough, most of the time their behaviour does follow our models, and we want to understand why this is.

Insects are short-lived: most of the time they live for a couple of hours, and sometimes a couple of days, so they have to be really accurate in the way they organize and manage their time. The insects that we are investigating are parasitoids, which means that they lay their eggs in other insects, and kill the host when the eggs produce larvae and eat the host. These parasitoids therefore act as insecticides, and so we are using them for biological control of the nasty insects that are attacking our crops. When we are studying what pushes those insects to optimize the number of progeny they produce, we also understand how they maximize their impact on the pest, and so our research has an applied perspective.

I spend a lot of time on really tiny insects, less than a millimetre long. These are the most intensively produced animals on the planet, with “factories” that produce zillions of insects. In Europe, we release about 300,000 insects per hectare of corn, and we treat several hundred thousand hectares of corn all over Europe.

What is an example of insect reproduction behaviour that you're researching?

The insects we are working with are able to do a lot of things that we, humans, cannot do. For example, they are able to decide the sex of their progeny, and they have a specific mechanism that allows them to choose whether to lay a male or a female egg. We want to understand how they use such mechanisms to maximize their reproductive output. We have found that they lay males and females in specific sequences that we can describe statistically. Hence, we produce mathematical models to predict whether a male or female will be laid in a specific situation, and then we test these models by creating experiments that place the insects in such scenarios.

Insects are really convenient to experiment on. You have a new generation each week, it costs almost nothing to breed them, and you can do really accurate experiments in a lab with cameras, computers etc. Although the biological models we use could also, hypothetically, be tested on other animals, it is definitely easier to experiment on insects than elephants!

How did you first get into the field of ecology?

My university career has been in a field that lies somewhere between maths and biology – biometry – which applies mathematical tools, especially statistical tools and computer science, to biology. I have always been more interested in the mathematical approach.  Biologists spend their entire life collecting data, which they have to analyse it in the correct way, and this is my niche. The fact that I'm more on the theoretical side means that there are always people knocking on my door trying to ask me how to develop theoretical models for their own insects, so I am working on a lot of insect species.

How has your time been at the IIAS so far?

It's a really great opportunity. I was extracted from my day-to-day work and I can really focus on my research. Together with Tamar Keasar and Michal Segoli, we were able to build a dream team. Most of the members of our group have all known each other for decades, and we are all friends, so it is not only scientific and academic activity here, there is also the social dimension, which is lovely. I am really enjoying it. Our group is here for 5 months, but I wish we were here for longer!

What do you like to do outside of your research?

I am a guitar player, but I am a really poor guitar player. I enjoy bossa nova, which is Brazilian jazz music that was famous in the 60s and 70s, and that is the style of music I like to play. I also love art, and have enjoyed visiting the Tel Aviv Museum of Art and the Israel Museum.

Can you tell us a bit about the short film you created?

A few years ago, I received a grant from the European Science Foundation to make a 30-minute film on parasitoids. The film explains the theoretical models used to make predictions about the efficacy of the parasitoids when trying to control pests.

The film was made for the general public, and was created with open access, so anyone in the university system can use it for teaching. The film is made in a Sherlock Holmes detective story style that surveys Europe. We designed some cartoons for it, and we also had a musician to compose the music. It took eight months to write, and four months to shoot, so it was a whole year of work! I was in charge of the scientific part, and I connected with professional filmmakers for the production. The movie was a real success, and we received some international awards for it.

Click here to watch Eric Wajnberg's 2009 film on parasitoids

What research are you working on during your time at the IIAS?

My Research Group is working on the topic of biological control, which is the method of controlling agricultural pests through natural predation. This method reduces the use of insecticides, which are unhealthy, costly, and are becoming less effective over time, because the pests are evolving insecticide resistance. The question is how to do biological control in the best way. Previously, people have experimented with different forms of biological control, with some success and some failure, and without using theoretical insights to plan biological control programs.

An alternative method is to look at the basic science of ecology, which describes how populations behave and interact. There are many models that predict what would happen if you were to put two populations, or several populations, together. So our groups is integrating those two methods: to use experimentation alongside ecological models to improve the practice of biological control. Our group is composed of experimental biologists who go out to the field and do biological control in practice, as well as biologists who come more from a theoretical background and have an interest in biological control. So we're trying to get everybody to collaborate and exchange ideas in order to develop improved theories and practices.

Are you focusing on a specific pest species?

We are looking at a broad range of species. We meet with different people here in Israel who are working on specific pests and specific biological control programs, and discuss with them what's bothering them and where they need solutions, so this gives us additional ideas for species to study.

For example, we have a colleague who is an applied biologist working on a specific moth species. The larvae of this moth bore into tomato fruits, and cause a lot of damage. This is a huge issue, because tomatoes are widely grown in Israel and are a big cash crop, so any harm to this crop creates a lot of economic damage. The moth has a natural predator, a predatory bug that is naturally present in those fields, and feeds on the pests. The challenge we were posed was to figure out what population size of predatory bugs is needed in order to sufficiently keep the moth population under control, so that insecticides don't need to be used on the crops. Our group worked together, and made the calculations, and we met with her to discuss our results. This is an example of a specific problem that we can tackle with the help of mathematical modelling.

Do you have a lot of opportunities to visit farms as part of your research?

Yes, we work with real farms and real farmers, and part of the job is learning to talk to them and get their cooperation, because they are really important for these studies. We are trying be useful and to address people's needs. It is also important to talk in a language that they can understand and accept, because sometimes academics use fancy terminology which is unclear to the farmer, so communication is really important.

How did you first get interested in this field?

My PhD was on insect behaviour, and the research didn't have any applied use, it was trying to understand what dictates decision-making in bees as a model for learning about other animals, and maybe even humans. When I did my postdoc, I switched to behaviour, learning and decision-making in parasitic wasps, which are actually natural enemies of agricultural pests. When I started my own lab, new students presented their ideas and their research interests, and I found that many of them were interested in these applied topics, and wanted to make a difference in the world. I adopted their point of view and got into more applied research, which I have really found fascinating. So I learnt from my students.

What's an example of how the behaviour of bees can be reflected in human behaviour?

One finding from my PhD research was how bees allocate their efforts between searching for food in known food sources, and trying out new locations. It's a question of curiosity: would curiosity for something new be a constant in all situations, or would it be situation-dependent? And I found that there is some dependence on the situation. When the bee knows that its environment is very variable and uncertain, then it will be more willing to try new things. And when it is very confident that everything will stay the same, then that tendency decreases. And I think humans work in the same way too, so it's nice to see that it’s a common principle.

How are you enjoying your time at the IIAS so far?

It’s a really lovely opportunity to have time to think, and to write. I really enjoy the interactions with my Research Group, and also with the other Research Groups at the Institute. I don’t normally have many interactions with academics from the Humanities, and so this is really exciting for me. Also, I did my PhD here at The Hebrew University, two buildings away, so it's great to be back on this campus!

Outside of your research, what do you like to do in your spare time?

I like hiking and gardening. Now, in the spring, I spend a lot of time in my garden.

Do you have a favourite hiking trail in Israel?

The Negev highlands and the area of the Ramon crater are very dramatic, and the landscape is different to anything else. It's such an open area, and there are very few people, so it’s the perfect peaceful place to walk, and think, and enjoy the view.

And finally, do you have a book recommendation for us?

Before I came to the IIAS, I spent a few months in London. I read a few books about London, written by people who'd visited London, and one of them is London Observed by Doris Lessing. It’s a collection of short stories, all set in London, and they show different parts of the city and different people in the city, from an outsider's viewpoint. The author immigrated to London in the late 1950s, and she wrote this collection of stories during her first years there when she didn't know the city well. She observed it as a visitor, and so when I came as a visitor to the same city 50 years later, it was very exciting to read her perspective.

What research are you working on during your residency at the IIAS?

My area of research is medieval Jewish history, focusing mainly on the social life of the Jewish communities in 'Ashkenaz', that is, France, Germany, part of Italy, and England. I'm looking at the interactions within the Jewish community, as well as the interactions and conflicts of Jews with their Christian neighbours.

I am curious as to how the Ashkenazi Jewish communities survived during the Middle Ages, despite internal and external threats. I am also interested in the role of women and children in this survival process. In my book Yihud ve-ha-Yahad (Uniqueness and Togetherness), I argued that the survival of the Jewish communities throughout the Middle Ages was thanks to the creation of massive and unique organizations that allowed successful socialization processes. Through these, individuals were taught beliefs, values and behaviours. Since these processes took place in the synagogue, I have studied the synagogue as a social institution, rather than as a place of prayer. 

The socialization processes are also evident in the prayers. Jewish prayers in the Middle Ages are a unique source of information. It appears that prayers were constantly added to the main section of the prayerbook, and these prayers contain numerous hidden messages pertaining to everyday life, as well as hinting to the Jewish community's relationship with Christianity. Hence, liturgy can profitably be used for the study of social history. By looking at liturgical poems in prayerbooks and by using medieval commentaries on these poems, I try to understand how Jewish socialization processes evolved, and what made them so effective.

Can you give an example of a prayer that hints towards these socialization processes?

An excellent case in point is the liturgical prayer for Shavuot (Pentecost). One of the main themes in the celebration of Shavuot is the reception of the Torah from God on Mount Sinai. In the 12^th century, the Christians claimed that the covenant between the Jews and God had become void with the passion of Christ, and that the Torah had been passed on to the Christians – the 'New Israel' – instead. In response, the Jewish paytanim [i.e. authors of the liturgical poems] composed a liturgical poem based on Midrashic sources, describing how God used the Torah to create the world, thus implying that the connection between the Torah and the Jewish people precedes even the creation of the world, and as such, the bond between God and the Jews is unbreakable. In this example one can see how the paytanim used liturgical poetry to challenge Christian beliefs and theological claims, and at the same time strengthened the Jewish faith.

Such liturgical poems are often accompanied by illustrations, and, as can be seen in numerous handwritten prayer books, these drawings contain hidden messages as well. Hence, studying these liturgical poems with their commentaries and illustrations is an interdisciplinary enterprise that combines history, theology, literary studies and art.

Your research also touches upon the relationship between Jews and ex-Jews in the Middle Ages. Could you please say a few words on that topic?

My book, Apostasy and Jewish Identity in High Middle Ages Northern Europe: 'Are you still my brother?', explores the relationship between Jews who kept their faith, and Jews who converted to Christianity in the Middle Ages. Throughout the 11^th and 12^th century, the Jews who remained Jews were mainly trying to bring the ex-Jews back into the fold. But the 12^th and the early 13^th century was a challenging period for the Jews of Eastern Europe, featuring the violence of the Crusades and the emergence of blood libels. Consequently, by the end of the 13^th century, the idea was not so much to bring the ex-Jews back to the community, but rather to keep them as ‘distant brothers’. I would submit that the historical circumstances and the ever-growing tensions between Jews and Christians had a huge effect on the attitude of Jews towards their converted brethren.

You have also explored the role of Jewish women in your book, Jewish Women in the Middle Ages – A Quiet Revolution. Were there any surprising outcomes of your research?

Although the cheder [i.e. Jewish elementary school] was for boys only, in the 11^th and 12^th century Jewish girls were able to receive a solid good education at home. In addition, contrary to the assumption that women-only prayer services are a modern Jewish phenomenon, it appears that according to our sources, women-only prayer services were performed as far back as the 13^th century!

How has your time been at the IIAS so far?

Being at the IIAS reminds me of my sabbatical time at Cambridge University, where there is a friendly, social environment, and you can't help but bump into all your colleagues as you walk around the building. It’s fantastic! Not to mention that my current research requires access to manuscripts in the National Library of Israel [located on the Givat Ram campus of The Hebrew University], so the IIAS has given me a great opportunity to further my research in the optimal academic environment.