Diversity of “decision-making” in the blob

When it comes to choice, taking time to evaluate the different options exposes you to competition, while responding quickly leads to mistakes.

In an article published in Proceedings of the Royal Society of London B, Audrey Dussutour (CRCA-CBI Toulouse) and researchers from the Uppsala university (Sweden) demonstrated that even among unicellulars, there is a wide variety of behaviour in the ability to make good decisions.

Read more on the INSB-CNRS website (in french)


Phenotypic variability predicts decision accuracy in unicellular organisms.
Dussutour A, Ma Q, Sumpter D.
Proc. Biol. Sci. B 2019 Feb 13. DOI : doi.org/10.1098/rspb.2018.2825

Researcher contact

Audrey DUSSUTOUR, Tél. +33 5 61 55 64 41 ou +33 6 51 02 92 75

Fruit flies can transmit their sexual preferences culturally

The study, published on November 30, 2018 in Science, provides the first experimental toolbox for studying the existence of animal cultures, thereby opening up an entire field of research.

While the cultural process is often thought of as being the unique to humans, the existence of persistent behavioral variation that cannot be ascribed to genetic or ecological variation in primate or bird strongly suggests the possible existence of cultural transmission within certain vertebrate species. For the first time, researchers from the Évolution et diversité biologique (CNRS/UT3/IRD) laboratory of the Centre de Recherches sur la Cognition Animale (CNRS/UT3), along with their international collaborators, have demonstrated that all of the mechanisms required for cultural transmission actually exist in the fruit fly.

Drosophila, commonly called fruit flies, are known for their capacity to learn and copy the sexual preferences of their conspecifics after observing them copulating. Can this transmission, however, be considered as “cultural”?

Read more on CNRS website

Situation d'apprentissage : deux femelles 'observatrices' regardent un mâle vert s'accoupler avec une femelle 'démonstratrice' tandis qu'un mâle rose est rejeté. © David Duneau/Science


Etienne Danchin, Sabine Nöbel, Arnaud Pocheville, Anne-Cecile Dagaeff, Léa Demay, Mathilde Alphand, Sarah Ranty-Roby, Lara van Renssen, Magdalena Monier, Eva Gazagne, Mélanie Allain, Guillaume Isabel

"Cultural flies: Conformist social learning in fruitflies predicts long-lasting mate-choice traditions"

Science, 30 Nov 2018: Vol. 362, Issue 6418, pp. 1025-1030, DOI: 10.1126/science.aat1590


Researcher contact

Guillaume ISABEL, 05 61 55 75 82

Guillaume Isabel © CRCA

The domino effect in collective decisions of schools of fish

The researchers studied and modelled the propagation of information in schools of fish when they collectively change the direction of their movement.

The results, published on 25 April 2018 in the Proceedings of the Royal Society B, show that each fish mimics the behaviour of a small number of its neighbours and that this mechanism spreads from one person to another in the manner of a domino effect.

Collective movements of groups of animals are one of the most spectacular phenomena observed in nature, but the rigorous analysis of these phenomena is very recent and has only been made possible by technological advances in data acquisition and processing. These collective movements result from local interactions between individuals and are accompanied by the formation of large-scale spatial and temporal structures. They play a fundamental role in group defense, reproduction, or foraging, improving individuals’ ability to survive. To understand these collective phenomena, it is important to characterize the dynamics of interactions between individuals in a group.

Researchers from the CRCA-CBI in Toulouse, the Normal University in Beijing, and the University of Groningen in the Netherlands have studied a tropical fish species, the red nose (Hemigrammus rhodostomus), whose schooling behaviour is very pronounced.

“Social conformity and propagation of information in collective U-turns of fish schools”
Lecheval V, Jiang L, Tichit P, Sire C, Hemelrijk CK, Theraulaz G.
Proc Biol Sci. 2018 Apr 25 ;285(1877). pii : 20180251. doi : 10.1098/rspb.2018.0251.

Researcher contact
Guy Theraulaz

Bees understand the concept of zero

The zero, which symbolizes nothing, the neutral or the absence, being a relatively recent human construction, these results, published in Science on June 8, 2018, question the symbolic importance of the zero in the history of mathematics.

It had already been shown that some vertebrates mastered complex numerical concepts, such as addition or zero, but nothing had been proven in insects. Since bees can count at least 5, researchers have trained them in the concept of “bigger than” and “smaller than”.


Scarlett R. Howard, Aurore Avarguès-Weber, Jair Garcia, Andrew Greentree, Adrian G. Dyer.
“Bees extrapolate ordered relations to place numerosity zero on a numerical continuum”
Science, 2018. DOI:10.1126/science.aar4975

Researcher contact
Aurore Avarguès-Weber