Quantum-like perception entanglement leads to advantageous collective decisions

Social animals have to make collective decisions on a daily basis. In most instances, these decisions are taken by consensus, when the group does what the majority of individuals want. Individuals have to base these decisions on the information they perceive from their socioecological landscape. The perception mechanisms they use can influence the cost of collective decisions. Here I show that when group-living individuals perceive their environment concurrently for the same decisions, a quantum-like perception entanglement process can confer less costly collective decisions than when individuals collect their information independently. This highlights a mechanism that can help explain what may seem to be irrational group-living behavior and opens avenues to develop empirical tests for quantum decision theory. Social animals, including humans, make collective decisions for many facets of their daily lives (1, 2). Collective decisions have evolved in group-living species because they appear to be less costly than personal decisions when individuals try to maintain group membership. However, some observed features of collective decisions can seem irrational. For example, group decisions appear to be more accurate as group size increases, even when individuals are uninformed (2). A number of models have been developed to try and explain emergent collective behavior as well as infer the mechanisms through which collective decisions occur (2-4). In all cases, we assume that individuals collect information, in some form or other, to make a decision (1). However, the influence of perception systems on this process has received little attention to date. Before making a decision, individuals have to perceive the landscape in which they find themselves (5). In short, individuals have to generate knowledge from their socioecological landscape by first acquiring information from data (the landscape, Figure 1a) (6, 7). This mechanism involves two error processes: when the individual generates information from data and when the individual generates knowledge from the information it receives. Perception mechanisms are involved in generating information and therefore play a critical, yet unassessed, role in collective decisions. Importantly, one advantage of group living is shared perception. That is, the reliance of individuals on others to be vigilant (8) or find resources such as food (9). When individuals rely on others for perception, the knowledge generation process described above will co-vary between individuals within a group (Figure 1a). Eavesdropping, when one individual acquires information from the knowledge generation process of others, is a process that can drive this covariance (5, 9). Eavesdropping is thought to be prevalent in echolocating mammals (10-13). In such instances, silent individuals can receive the same information as echolocating conspecifics by listening to the echoes from the calls those produced. They can then use this information for a range of behavioral decisions (11, 12). However, this process is not exactly eavesdropping (Figure 1b). What we have instead is an entanglement in the information generation process between individuals present together in a group. This perception entanglement is an extreme case of perception covariance between group members which offers an interesting avenue to assess how perception mechanisms might affect collective decisions.