Preference for the nearer of otherwise equivalent navigational goals quantifies behavioral motivation and natural selection.

Navigation and environmental perception precede most actions in mobile organisms. Navigation is based upon the fundamental assumption of a ubiquitous Preference for the Nearest of otherwise equivalent navigational goals (PfN). However, the magnitude and triggers for PfN are unknown and there is no clear evidence that PfN exists. I tested for PfN in human participants on a retrieval task. Results of these experiments provide the first evidence for PfN. Further, these data quantify the three primary PfN triggers and provide an experimental structure for using PfN as a behavioral metric across domains. Surprisingly, PfN exists at a high, but not universal, magnitude. Further, PfN derives most from the absolute distance to the farthest of multiple goals (d(f)), with little influence of the distance to the nearest goal (d(n)). These data provide previously unavailable quantification of behavioral motivation across species and may provide a measurable index of selection. These methods hold particular import for behavioral modification because proximity is a powerful determinant of decision outcomes across most behaviors.