Olfactory Search Behavior Across Flow Regimes Supports a Unifying Framework

How animals perform odor-guided search across the broad range of dynamic flow conditions they encounter in nature is not well understood. Prior work treats established strategies such as circling and zigzagging as discrete, context-dependent behaviors. Here, we propose a parsimonious mathematical framework that unites these motifs into a continuum. We show that free flying Drosophila exhibit this continuum by smoothly reshaping search behavior between circling and zigzagging across unsteady flow, still air, and a range of wind speeds. Strikingly, a flow-invariant rhythmic course progression underlies this behavioral spectrum. Available data from moths and sharks across different flow regimes suggest a similarly preserved rhythm, while the rate of this rhythm varies across taxa. Together, these results support a common conceptual basis for olfactory search behavior and explain how search geometry can adapt automatically to local flow.