As humans, we tend to intuitively follow the gazes of others. But do pigeons do this, too? What role does group behaviour play in the process – and what does this tell us about the animals? A behavioural experiment by the Cluster of Excellence Collective Behaviour at the University of Konstanz in collaboration with Kyoto University.

There's something magnetic about a group of people looking in the same direction – others will follow their gazes to see what has caught their attention. But is the same true for animals like pigeons – and, if so, does it make a difference, if just one pigeon or a large group of them looks at something? A team of animal behaviour researchers around Fumihiro Kano (team leader) and Mathilde Delacoux from the University of Konstanz examined the gaze following behaviour in groups of pigeons. A story about why it is important to know where pigeons are looking.

Following the gaze
Gaze following plays a particular role in behavioural research. "Many animals, including humans, tend to look where others are looking, this is called gaze following. It’s a simple but important way of sharing attention and learning from others", Mathilde Delacoux explains. True to the motto: I think that you think there is something interesting there – so I'll have a look for myself.

In a famous behavioural experiment that has been copied countless times, especially using flash mobs, US American social biologist Stanley Milgram studied how people follow the gazes of others. For example, a group of people stares at the roof of a building. When the group reaches a certain size, passersby stop and look in the same direction. Milgram concluded that a minimum number of people is required for the effect, which he fittingly named the "quorum effect".

But does this also apply to the animal kingdom? Do animals also follow the gazes of others? Is there a quorum effect for animals, too? And can we really learn something about their cognitive performance by studying whether they notice what others are looking at?

Past studies with birds such as ravens, starlings, geese, penguins, nandus and emus have shown that they follow the gazes of their fellow creatures, indeed. Yet, these behavioural experiments were conducted with only two animals at a time: one bird looks at something, and the other follows its gaze. Now, what role does group behaviour play in the process? Is group size perhaps the deciding factor, as Milgram demonstrated with humans? These are the questions that Delacoux and Kano asked while studying pigeons. "Pigeons are well-suited to this task because they typically form relatively large flocks, where individuals are usually surrounded by multiple conspecifics. In such flocks, following another’s gaze should be beneficial for key activities such as foraging and vigilance", Delacoux says.

In the high-tech barn
In the special setup of a high-tech barn in Möggingen by Lake Constance, the researchers positioned two groups of pigeons opposite each other. One group was shown a moving object that aroused their attention – while it remained hidden from the other group behind a barrier blocking their view. The researchers wanted to know: Would the second group look in the same direction as the others? How reliably does this effect occur? And does the number of animals staring in the same direction play a role in this?

For the experiment, the pigeons were observed using a camera system that measured their head movements from different perspectives in real time. This allowed the researchers to reconstruct precisely to the millisecond the time at which each pigeon was looking in a specific direction – and how each one responded to the gazes of others. Delacoux and Kano repeated the experiment in several different group compositions: with only one pigeon able to see the object or with many of them, three, five or more.

The experiment confirmed the researchers' hunch: The pigeons did indeed follow the gazes of others. However, the effect was less pronounced than had been previously observed in other bird species. It was also evident that group size really does play a role. When just one pigeon stares in a particular direction, others rarely follow its gaze. Yet, as soon as several pigeons look in the same direction, most of the others do likewise.

Unlike in Stanley Milgram's experiment, there was, however, no sign of a quorum effect. This means: Although the number of pigeons truly does play a role, there was no specific minimum amount of pigeons needed to produce the result. What the team observed was more of a linear increase: The greater the number of pigeons staring in the same direction, the more other pigeons joined in the behaviour – without there being a minimum number required for this action.

Peering into the minds of pigeons
Now, what does this experiment tell us about the cognitive abilities of pigeons? Is the experiment a sign that pigeons can take the perspectives of others? Mathilde Delacoux is cautious with interpretations: "I would not assume that their behaviour means any more than that they are just following the gazes of others". Delacoux thinks the pigeons' reaction is more likely reflexive in nature. There were no visible signs of deeper cognitive abilities – such as changing one's position to get a better view of the hidden object.

At the same time, the results do indeed provide insight into the group behaviour of pigeons. “Now, we know pigeons don’t just copy their flockmates gaze, they modulate their gaze following behaviour depending on how many peers give a gaze cue”, Fumihiro Kano says and emphasizes: "They respond to a collective cue". The research results indeed enable a peek into the minds of pigeons, and they show us social behaviour that uses the group for orientation. An individual gaze may go unnoticed, but many gazes will attract attention – not just in the case of humans, but for pigeons, too. As Kano puts it: “Many animals evolved in groups. To truly understand how they think and communicate, we need to study them in groups, too.”

Key facts: Original publication: Mathilde Delacoux, Akihiro Itahara, Fumihiro Kano, Gaze following in pigeons increases with the number of demonstrators, iScience, Volume 28, Issue 7, 2025, DOI: https://doi.org/10.1016/j.isci.2025.112857. Link: https://www.sciencedirect.com/science/article/pii/S2589004225011186 Research project of the Cluster of Excellence Collective Behaviour at the University of Konstanz in collaboration with Kyoto University.