Ariana Strandburg-Peshkin

Group Leader

astrandburg at

I study the mechanisms and consequences of collective behavior in biological and social systems. I am especially interested in understanding how animal groups make collective decisions and coordinate collective action, and in particular how these processes are affected by the social relationships between group members and the communication strategies they employ. I work across a range of study systems to tackle these questions, in close collaboration with researchers across a variety of disciplines.

Originally from Chicago, I did my undergraduate degree in Physics at Swarthmore College, then did my PhD in Quantitative and Computational Biology at Princeton University. I then moved across the pond to Europe, where I held post doc positions at the Max Planck Institute for Ornithology and the University of Zurich before moving to Konstanz in 2018. When not working, I enjoy traveling (especially via Swiss transit), cooking, eating, riding my bicycle, and learning German.


Vlad Demartsev

Postdoc (Humboldt Fellow)

vdemartsev at

I am a behavioural ecologist interested mainly in the topics of mammalian vocal communication in social settings. For the past 9 years, I have focused on the interplay between different aspects of the social environment with different aspects of signalling tactics and signal structure. I have investigated how the presence, composition and attentive state of conspecific audience affect individuals` signalling behaviour. On the flip side, I have explored how individuals` are able to maximize their gain from signalling and reach a more abundant and attentive audience by correctly timing their signalling events and also producing signals which are more effective in gaining and maintaining audience attention.

Currently, I am in the process of conceptually and methodologically developing a project dealing with the motivational phase of vocal signalling in an attempt to detect the animals' preparations and intentions to vocalize. Additionally, I am also interested in investigating animals’ ability to maintain continuous vocal interactions which include multiple interactions turns and dynamic informational content.  I have a very strong preference for field-based, experimental studies, as they allow us to witness animal behaviour in its natural ecological and biological contexts. 


Vivek Hari Sridhar


vsridhar at

I'm an evolutionary biologist interested in the interplay between individual and group level properties in animal societies. More specifically, how selection operating on decision rules adopted by individuals affects collective motion, environmental sensing, information propagation and collective decision making, and how these group level properties in turn affect individual fitness. Currently, I analyse GPS-based movement data, and acoustics to understand how meerkats use vocal communication to coordinate movement.

Prior to this, I completed my PhD in the Department of Collective Behaviour, also at the Max Planck Institute of Animal Behavior where I used theory and experiments to study decision-making in insects and fish, and leadership in fish schools.


Gabriella Gall

Postdoc (Zukunftskolleg Fellow)

gabriella.gall at

My current research aims to understand how differences in early experiences can affect an individual’s ability to coordinate effectively with group members later in life and whether and if so, how these differences ultimately affect individual fitness. I address these questions using two study systems, the domestic chicken and the common pheasant, and make use of the fact that both species are highly vocal and use acoustic signals to coordinate group activities. This work is in close collaboration with Prof Madden (University of Exeter) and Prof Radford (University of Bristol).

I completed my PhD on meerkat group coordination and decision-making at the University of Zurich, after which I studied the effect of anthropogenic disturbances on the social cohesion of California ground squirrels in collaboration with Dr Smith at Mills College. I also did a postdoc with Dr Meroz at Tel Aviv University to study the self-organisation of mutually shading sunflower plants. When not at work I love everything related to the arts and crafts and always appreciate a donation of wine-corks.


Nico Gradwohl

Postdoc (CASCB)

nico.gradwohl at

My current work addresses how consensus formation in human groups is affected by the ways in which individuals shape their communication networks over time. Relying on online group-experiments, we ask to what degree individuals seek out the opinions of different or similar others. Thereby, we are especially interested in whether minorities can create communication structures that convince individuals who are actually the majority to adopt the minority opinion. I am currently working on an interdisciplinary endeavor together with Helge Giese and Ari, including both psychologists and biologists.

After having completed my M.Sc., I am about to receive my PhD in Psychology, which I did in Wolfgang Gaissmaier’s working group on Social Psychology and Decision Sciences at the University of Konstanz. I am fascinated by the various ways in which human decision making is affected by the presence of others. Thereby, my main interest circles around the strategies that individuals use to navigate their complex social surroundings, requiring us to manage competition for limited resources, integrate the information available and coordinate our actions with others.


Baptiste Averly

PhD Student

baverly at

I am interested in understanding how animals within social groups perceive and interact with one another, exchanging and exploiting information to adjust their behaviour in different ecological contexts. What particularly fascinates me is the question of how local interactions between individuals can scale up to complex and relevant group-level responses that are more than the sum of their parts. After undergraduate studies in France and Canada, for my Master’s thesis I studied the use of social information in multi-species flocks of tits foraging during winter along an altitudinal gradient.

For my PhD, which I started in September 2018, I am collecting high-resolution spatial and acoustic data on whole groups of meerkats in their natural habitat using custom-made collars, to understand how collective decision-making is achieved during group movement in this social species with complex vocal communication. Of particular interest to me is the way individual variations and social structure can influence how pairs of individuals respond to one another in different contexts of movement, and how this ultimately affects patterns and processes at the group level.


Emily Grout

PhD Student

egrout at

I am interested in the behavioural ecology of social mammals, with a focus on field-based data collection. My undergraduate degree was in Zoology at the University of Bristol, where I continued as a masters by research student. For my masters, I studied alloparental care in a habituated population of wild dwarf mongooses in South Africa at the Dwarf Mongoose Research Project. I collected detailed observations of adult-pup interactions to assess the different types of alloparental activities which are exhibited and whether dominance status, sex and age influenced variation between these caring tasks.

For my PhD, I will be studying communication and collective movement of white-nosed coatis, which live in forested areas in the Americas. I will be recording acoustic and movement data from the majority of coati group members using custom built collars to analyse how group cohesion is coordinated and maintained through acoustic communication. I am excited to be combining detailed field-based observations with new tracking technologies to answer questions about the mechanisms underlying collective movement in social mammals.


Pranav Minasandra

PhD Student (DAAD Fellow)

pminasandra at

I am fascinated by behaviours exhibited by animal collectives, such as movement and synchronisation. I am also intrigued by computational and theoretical methods in biology, and love handling interesting datasets. My Master's and Bachelor's, both in biology, were completed in the Indian Institute of Science, Bangalore. There, I worked on grouping in blackbuck, collective track formation by herbivores, and several other problems. In collaboration with Ari, during my master's I studied behavioural dynamics using accelerometry of spotted hyenas.

During my PhD, I will look at the synchronisation of wake-sleep cycles in social animals, using cichlids as model organisms. For this, I will use model fitting to test whether social factors affect circadian rhythms. I am particularly glad that the project is quite open-ended, and thus allows me to approach the problem from computational, theoretical, and experimental approaches.


Julián León

Visiting PhD Student (SNSF Mobility Fellow)

julian.leon at

I am interested in the behaviour, cognitive mechanisms and socioecology of primates, with a focus on combining ethological observations and experiments on the field to explore primate communication. I completed my Bachelor's and Master's studies in Colombia, where I studied the social and vocal behaviour of woolly monkeys and the patterns of acoustic variation and the transmission of the information contained in the contact calls of brown spider monkeys, respectively. Later, I worked on different projects studying the ecology and mammal’s diversity in tropical forests and the social system, grouping patterns and vocal communication of different neotropical primates.

For my PhD, under the supervision of Professor Klaus Zuberbühler (University of Neuchâtel, Switzerland), I am studying the vocal communication system of free-living sooty mangabeys in West Africa, to understand how non-human primates acquire their communicative capacities and skills and the role of socially learning in this process. For the last part of my PhD research, I am collaborating with the CoCoMo group to explore the effects of the social environment on the acoustic structure and call usage of sooty mangabey vocalizations across time. Here, I intend to use unsupervised clustering methods to compare the change in the vocal profile of a sooty mangabey group at different points of time in a twenty-year period.


Ingerid Helgestad

Research Assistant

ih279 at

I am working as a research assistant to Gabriella Gall with her study system on domestic chicks. In addition, in collaboration with Gabriella and Tim Fawcett (University of Exeter), I conduct experiments using thermal cameras to assess the chicks’ physiological responses to conflict. I am also working with Lisa Leaver (University of Exeter) on a project looking into the biomechanics of how eastern grey squirrels jump.

I have a BSc in Psychology and an MSc in Animal Behaviour from the University of Exeter. During my master’s degree I conducted a research project under the supervision of Sam Ellis where I looked at quantification of social complexity in the context of the social intelligence hypothesis. For my bachelor’s thesis I worked on a project investigating the role post-reproductive female killer whales play in regulating aggression within the group, with Darren Croft.


Sharaj Kunjar

BSc Student (IISc Bangalore)

sharajk at

Hey there! I am interested in mathematically modelling collective behaviour, specifically in the context of relatively large social systems. I am currently doing my Bachelor (B.S. Research) in Physics, from the Indian Institute of Science (IISc), Bangalore. I have been an intern under Ari since July 2021, who along with Nico Gradwohl and Helge Giese, has been guiding me through my interdisciplinary interests.

Owing to my physics background, my understanding of complex social systems stems from the methods and mathematical tools from statistical physics. My current work, in close collaboration with Nico, involves mean-field modelling of large groups to understand the role of personal preferences in consensus decision-making scenarios. This includes quantifying innate human qualities like stubbornness, modelling strategies and using numerical simulations to identify social tipping points. I intend on continuing to explore complex social behaviour for my bachelor's thesis.


Rebecca Schaefer (Field Assistant, 2019)

Bec assisted with data collection during the 2019 field season at the Kalahari Meerkat Project.

Katja Della Libera (Undergraduate Thesis Student, 2020-2021)

Katja analyzed fission-fusion dynamics in sheep using GPS data, in collaboration with Dr. Stephan Leu. 

Mathieu Duteil (Postdoc, 2020-2021)

Mathieu developed evaluation metrics for the detection and classification of calls, in collaboration with Dr. Marie Roch.

Pauline Toni (Field Assistant, 2021)

Pauline assisted with data collection during the 2021 field season at the Kalahari Meerkat Project.

Camille Lysemna (Field Assistant, 2021)

Camille assisted with data collection during the 2021 field season at the Kalahari Meerkat Project.

Kiran Dhanjal-Adams (Postdoc, 2019-2021)

Kiran developed machine learning tools for the detection and classification of calls, in collaboration with Dr. Marie Roch.

Mara Thomas (MSc, 2020-2021; Postdoc, 2021)

Mara used unsupervised dimensionality reduction and clustering to characterize the meerkat vocal repertoire.