• Dr. Léa Briard

    Behavioural Biologist

    My Research

    I am a Postdoctoral Fellow in Dr Audrey Dussutour's lab at the Research Center on Animal Cognition, Toulouse (France). My project is supported by the French National Research Agency (ANR). I am studying slime molds, their cognitive abilities and their behavior when parasited.


    My previous research investigates the effect of gastrointestinal parasite on host behavior. In the Ezenwa lab (University of Georgia, USA), I studied the effect of helminths on cotton rats' behaviors. Before that I had studied how gastrointestinal parasites affected food choices in domestic horses and collaborated with parasitologists and chemists to identify potential bioactive compounds.


    My PhD research addressed how social animals reach consensual decision on where and when to go. In particular, I studied how individual and social characteristics influence the dynamic of collective movements. Through the meticulous observation of groups of horses, my PhD research provided evidences in favour of a certain universality of rules underlying decision-making processes in animal societies.

  • What I'm Up To

    Parasitism, nutrition and cognition

    What can slime molds do ?

    Parasitism and personality

    Causality in the parasite - host behavior relationship

    Differences in activity, boldness or exploration have been shown to influence space use and the chance of discovering new resources while increasing the risk of acquiring new parasites. However past studies have have used naturally infected individuals prior to behavioural assay, making interpretation of causality challenging. This project aims to study the causal relationship between parasite risk and host personality using an experimental modification of individuals' parasite load.

    Parasitism and food choices

    Self-medication in horses ?

    I had the opportunity to witness interesting feeding behaviors in horses I was studying for my PhD. I noticed that individuals that were not treated with anthelmintic drugs ate much more often on trees. Interestingly these trees were already known for their anthelmintic and antalgic properties (e.g. Salix sp.). Using a bottom-up approach, I collected fecal and plant samples, and recorded food choices and discomfort behaviors in 20 domestic horses.

    Collective behaviours

    Influence of social and individual characteristics on group decision-making

    Living in groups is challenging on many levels for animals and one of this challenge is the maintenance of group cohesion. How animals that do not share the same motives or needs, decide collectively where and when to go, to rest or to eat? During my PhD, I studied the mechanisms underlying collective decision during group movements in domestic horses, and notably the influence of interindividual differences and social relationships on those mechanisms.

  • Publications


    7 - Boussard A., Fessel A., Oettmeier C., Briard L., Döbereiner HG & Dussutour A. Adaptative Behavior and learning in slime moulds: the role of oscillations. Phil Trans R Soc


    6 - Briard L., Deneubourg JL. & Petit O. Group behaviours and individual spatial sorting before departure predict the dynamic of collective movements in horses. Animal Behaviour


    5 - Briard L. & Ezenwa VO. Parasitism and host social behaviour : a meta-analysis of insights derived from social network analysis. Animal Behaviour


    4 - Briard L., Gourjade C., Bousquet C. & Dussutour A. 2020. Stress signaling in slime moulds and its perception by conspecifics. Phil Trans R Soc.


    3 - Briard L., Deneubourg JL. & Petit O. 2017. How stallions influence the dynamic of collective movements in two groups of domestic horses, from departure to arrival. Behavioural Processes


    2 - Briard, L., Dorn, C. & Petit, O. Personality and affinities play a key role in the organisation of collective movements in a group of domestic horses. Ethology

    - Coverage by the press: Jezebel.com


    1 - Sueur, C., Briard, L. & Petit, O. Individual analyses of Lévy Walk in semi-free ranging Tonkean macaques (Macaca tonkeana). PLoSONE 6, e26788. doi:10.1371/journal.pone.0026788

    L. Briard, J. Brunet, E. Candolfi, O. Petit. Parasitisme et réseau social : lien entre la charge parasitaire et le statut social du cheval vivant en troupeau, 17 mars 2016, Paris, Institut Français du Cheval et de l’Equitation. Paris : édité par l’IFCE, 2016

    - Coverage by the press: TheHorse.com


    L. Briard, O. Petit. Resocialisation d’un étalon au sein d’un groupe de juments : reconstitution de la structure naturelle du cheval : acte de la 40ème Journée de la recherche équine, 18 mars 2014, Paris, Institut Français du Cheval et de l’Equitation. Paris : édité par l’IFCE, 2014.

  • Welfare & Rehoming

    Animal Welfare

    3F: Friends, Forage and Freedom

    Studying a domestic species made me more aware of the condition of domestic animals both at home and in farms. I gradually discovered that, although my research was mainly fundamental, my results could help increasing general knowledge about domestic animals and their fundamental needs!

    I have helped reintegrating stallions in social groups that have had lived in isolation for most of their life.

    I also wrote press articles and participate to public conferences to disseminate the latest information on animal behaviour to a broader audience.

    The 4th R

    Replace, Reduce, Refine... and Rehome !

    I have been volunteering for 7 years for a french organization specialized in the rehoming of lab animals, named le G.R.A.A.L. The principle is to offer research institutes an alternative to the euthanisation of healthy lab animals. Since 2005 this association has rehomed thousands of animals such as rodents, fish, horses, dogs, cats, rabbits, pigs, lambs, primates. For more information:


  • Curriculum


    2006 - 2015

    • 2015. PhD in Ethology

    Decision-Making processes during collective movements in domestic horses (Equus ferus caballus). PDF here

    Supervised by Dr. Odile PETIT (University of Strasbourg, France) and Pr. Jean-Louis DENEUBOURG (Free University of Brussels, Belgium)


    • 2011. MSci in Ecophysiology and Ethology. 

    Master thesis "Social network influences decision-making in a group of semi-free ranging white-faced capuchins"

    supervised by Dr. Odile Petit


    • 2009. BSci in Life Sciences

    University of Strasbourg

    3rd year at the University of Warwick (UK)


    • 2017. Post-Doc. Ezenwa's lab, Odum School of Ecology, University of Georgia (Athens, GA, USA)
    • 2016. Post-Doc. Institute of Tropical Parasitology and Pathology and Department of Ecology, Physiology and Ethology (Strasbourg, France)
    • 2013 - 2014.  Teaching Assistant. Faculty of Life Sciences University of Strasbourg, France.
    • 2011 - 2015. PhD candidate. Department of Ecology, Physiology and Ethology (Strasbourg) & Unit of Social Ecology (Brussels)


    • 2015. "Young Researcher" award. Des Treilles Foundation (France)
    • 2015. Best Presentation Award. 1st meeting for the students of the Equine Sector (IFCE/Hippolia)

    Acquired funds

    • 2016. Postdoctoral Research Fellowship. Fulbright Program
    • 2015. Postdoctoral Research grant. IFCE Research Fund
    • 2015. Grant from David and Alice van Buuren Foundation
    • 2015. Grant from de Meurs-François Fund
    • 2014. Sféca International Conference Grant. ECCB 2014 (Praha)
    • 2013. Sféca Conference Grant. Annual Sféca Conference (Dijon, France)
    • 2013. ASAB Conference Grant. BEHAVIOUR 2013 (IEC, Newcastle)
    • 2012. Travel and Accomodation Grant for co-supervised PhD candidate (From the Free University of Brussels and the University of Strasbourg)
    • 2011. Doctoral Fellowship. Ministère Français de l'Education et de la Recherche.
    • 2009. Study bursary for international exchange students (Erasmus, University of Warwick)
    • 2009. Excellence study bursary for undergraduate results
  • Get in touch