Shoals of fish often achieve things that individual specimens are unable to do. It is easier for fish to find food, to recognise enemies quickly, and to reproduce more successfully in a shoal. In the case of humans, too, decisions taken collectively often turn out to be better than those made by individuals. For this reason, social networks and collective decision processes are not only interesting for ecology, but also for decision management in politics, medicine or the economy. In these systems, principles such as competition, organisation, cooperation and resource management play an important role. For this reason, at IGB we explore how decision processes can be improved. For example, we use knowledge of the swarm behaviour of fish to derive models for the dynamics and organisation of groups of people.

Selected publications

September 2024
Functional Ecology. - 38(2024)10, 2123-2138

Evidence for a by-product mutualism in a group hunter depends on prey movement state

K. Pacher; J. Krause; P. Bartashevich; P. Romanczuk; P. Bideau; D. Pham; A. L. Burns; D. Deffner; F. Dhellemmes; B. Binder; K. M. Boswell; F. Galván-Magaña; P. Domenici; M. J. Hansen

Researchers from the Cluster of Excellence Science of Intelligence (SCIoI), in which the Humboldt-Universität zu Berlin (HU Berlin) and the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) are involved, have proven in an underwater field study in the ocean off Mexico: the faster a school of prey moves, the higher the capture rate of the striped marlin.

March 2023
Proceedings of the Royal Society B: Biological Sciences. - 378(2023)1874 Art. XX

Multispecies collective waving behaviour in fish

Juliane Lukas; Jens Krause; Arabella Sophie Träger; Jonas Marc Piotrowski; Pawel Romanczuk; Henning Sprekeler; Lenin Arias-Rodriguez; Stefan Krause; Christopher Schutz; David Bierbach

Groups composed of more than one species offer a unique opportunity to look into the evolution of both mechanistic and functional aspects of collective behavior. The study presents data on mixed-species fish shoals that perform collective dives. The dampening effect of less responsive gambusia on molly diving behavior can have strong evolutionary consequences on the overall collective behavior.

February 2023
Proceedings of the Royal Society B: Biological Sciences. - 290(2023)1992 Art. 20222115

Leveraging big data to uncover the eco-evolutionary factors shaping behavioural development

Sean M. Ehlman; Ulrike Scherer; David Bierbach; Fritz A. Francisco; Kate L. Laskowski; Jens Krause; Max Wolf

In this review, the authors provide a guide to state-of-the-art approaches that allow the collection and analysis of high-resolution behavioural data across development. They outline how such approaches can be used to address key issues regarding the ecological and evolutionary factors shaping behavioural development.

December 2022
Bioinspiration & Biomimetics. - 17(2022)6, Art. 065007

Live fish learn to anticipate the movement of a fish-like robot

David Bierbach ; Luis Gómez-Nava ; Fritz A. Francisco ; Juliane Lukas ; Lea Musiolek ; Verena V. Hafner ; Tim Landgraf ; Pawel Romanczuk ; Jens Krause

Schooling fish, moving synchronously in the water – how do they do that? Using a robotic fish, the authors have shown that guppies can anticipate the behavior of their artificial conspecific and predict both the direction and dynamics of its movements. So this is another explanation for why fish in a school – which know each other well – are capable of extremely fast collective movements

November 2022
Communications Biology. - 5(2022), Art. 1161

Mechanisms of prey division in striped marlin, a marine group hunting predator

M.J. Hansen; S. Krause; F. Dhellemmes; K. Pacher; R.H.J.M. Kurvers; P. Domenici; J. Krause

The authors identified individual striped marlin (Kajikia audax) hunting in groups. Groups surrounded prey but individuals took turns attacking. They found that competition for prey access led to an unequal division of prey among the predators, with 50% of the most frequently attacking marlin capturing 70–80% of the fish.

Related Projects

Experts at IGB

David Bierbach

Guest Scientist
Research group
Mechanisms and Functions of Group-Living
Behavioural Biology

Jens Krause

Head of Department
Research group
Mechanisms and Functions of Group-Living

Ralf Kurvers

Guest Scientist
Research group
Behavioural Biology

Max Wolf

Research Group Leader
Research group
Behavioural Biology