The diving gear is on, the cameras are ready – biologist Eduardo Sampaio and his colleagues are set to go. They dive in the Red Sea, scanning left and right underwater – and wonder: Where can an octopus hunting be found? Finally, they spot one. The team operates the two cameras they have with them, and station many more to collect data. Then, it's time to wait. Months later, after analyzing more than 100h of film material from dives in Israel, Egypt, and Australia, Eduardo Sampaio is more than pleased with the footage. The two camera perspectives have enabled him to create a 3D view of the scene – and provide him with novel insights into multispecies hunting.
- You can find a video and images from the octopus research here (from 23 September 2024 at 16:00 London time): https://www.campus.uni-konstanz.de/en/science/unlocking-the-secrets-of-multispecies-hunting
Utilizing advanced 3D field-based tracking and field experiments, Eduardo Sampaio observed that multispecies groups display unique and composition-dependent properties. "In groups of Octopus cyanea and various fish species, social influence is not evenly distributed but rather hierarchically structured across multiple dimensions, reflecting specialized roles within the group," says the biologist. Notably, fish, particularly goatfish, are responsible for environmental exploration, dictating the group's direction, while the octopus determines the timing and initiation of group movement.
In an intriguing display of ecological synergy, fish act as an extended sensorial system for octopuses, covering larger areas and enhancing prey detection efficiency. "This beneficial interaction enables fish to acquire otherwise unreachable prey, and octopuses to conserve energy by focusing on high-quality food sources, while exerting control and providing feedback within the group, highlighting the sophisticated dynamics of marine life collaboration," says Eduardo Sampaio.
New perspective on leadership
Leadership in animal groups, be it fish, birds, or apes, is usually associated with driving the group forward. However, this study shows that leadership can emerge from both the stimulation and inhibition of movement in others, with the octopus acting as the main influencer of movement through inhibition. Moreover, the group's composition significantly influences individual investment and collective action, revealing exploitation by different group members. Such prompts partner control mechanisms, mainly by the octopus, that punches the exploiters, reinforcing its position as the de facto leader. These actions help the octopus to maintain the benefits it receives from collaborative partners.
In concrete terms for the hunting situation this means: "When the octopus catches the prey it also kills it", says Eduardo Sampaio. "One item of prey is not divided, it is taken by whoever catches the prey first! However, because the interaction between the fish and octopus repeat several times during a hunt, prey is 'shared' in the sense that sometimes the octopus catches the prey, and other times fish catch the prey."
This research demonstrates that the otherwise solitary Octopus cyanea exhibits remarkable social competence and cognitive flexibility, adapting its behaviour in response to the actions of different species. "These results broaden our understanding of leadership and sociality, emphasizing the complexity and adaptability of social interactions in nature", summarizes Eduardo Sampaio.
Key facts:
- Under embargo until 23 September 2024 at 16:00 London time (11:00 US Eastern time)
- Sampaio, Couzin, Gingins et al.: Multidimensional influence drives leadership and composition-dependent success in octopus-fish hunting groups. Nature Ecology & Evolution. https://www.nature.com/articles/s41559-024-02525-2
- Eduardo Sampaio is a postdoctoral researcher based at the Max Planck Institute of Animal Behavior and the Cluster of Excellence Collective Behaviour at the University of Konstanz.
- Fieldwork was conducted at the Inter-University Institute for Marine Sciences (Israel), the Open Ocean Sciences Centre (Egypt) and the Lizard Island Research Station (Australia).
- The Cluster of Excellence Centre for the Advanced Study of Collective Behaviour at the University of Konstanz is a world-leading research centre for the study of swarm behaviour. It tackles pressing questions across species and organizational levels in an interdisciplinary manner, from neuronal mechanisms to individual perception and preferences to collective behaviour in groups or entire socities.
Note to editos:
Images and a video are available here:
Video (YouTube): https://youtu.be/8gCDfiZtkoo
Photos:
1: https://www.uni-konstanz.de/fileadmin/pi/fileserver/2024_EXTRA/der_oktopus/dsc02655.jpg
Caption: An octopus actively moving through the habitat, followed by a blacktip grouper, and being led by a long-barbel goatfish. © Simon Giggins
2: https://www.uni-konstanz.de/fileadmin/pi/fileserver/2024_EXTRA/der_oktopus/dsc00017.jpg
Caption: An octopus cyanea hunting with blacktip groupers around it. These species tend to exploit the octopus. © Eduardo Sampaio
3: https://www.uni-konstanz.de/fileadmin/pi/fileserver/2024_EXTRA/der_oktopus/vlcsna.jpg
Caption: A large multispecies group, composed by one Octopus Cyanea, two blue goatfish, one blacktip groupers, one lyretail grouper, and one broomtail wrasse. © Eduardo Sampaio
Caption: Eduardo Sampaio returns from a dive. © Victor Hugo Captain Darwin
5. https://www.uni-konstanz.de/fileadmin/pi/fileserver/2024_EXTRA/der_oktopus/eduardo_sampaio.jpg
Caption: Eduardo Sampaio diving in Israel © Marleen Franz
Key facts:
