All together now: Single rule accounts for diverse decision systems in animal collectives
(Phys.org)—Ethologists – those who study animal behavior under natural conditions – have long recognized that groups of various species, or animal collectives, use a variety of decision-making systems. For example, some species choose from among various behavioral options based on the number of animals that have already selected each alternative; other species follow Weber's Law, in which the relative number is the deciding factor; and for others, more complicated rules are involved. Recently, however, scientists at Instituto Cajal, Consejo Superior de Investigaciones Científicas, Spain, identified a single Bayesian-based decision-making rule underlying this observed diversity. Moreover, the researchers then experimentally demonstrated that this single rule quantitatively explains decision-making in zebrafish, and in existing datasets of argentine ants and sticklebacks. This suggests, they conclude, that decision-making based not just on individual behavioral, neurobiological, and psychological factors, but on social information, obtains across species – including humans.