Olfactory Search Behavior Across Flow Regimes Supports a Unifying Framework

Area of Science:

• Animal behavior
• Fluid dynamics
• Olfactory navigation

Background:

• Odor-guided search strategies like circling and zigzagging are traditionally viewed as distinct behaviors.
• The mechanisms animals use to navigate using scent in variable wind conditions remain unclear.

Purpose of the Study:

• To develop a unified mathematical framework for understanding odor-guided search behaviors.
• To investigate the underlying principles of olfactory search across diverse flow conditions and taxa.

Main Methods:

• Developed a parsimonious mathematical model unifying search behaviors into a continuum.
• Observed and analyzed the search patterns of free-flying *Drosophila* in various airflow conditions.
• Compared *Drosophila* data with existing data from moths and sharks.

Main Results:

• *Drosophila* exhibit a behavioral spectrum from circling to zigzagging that smoothly adapts to airflow.
• A consistent, flow-invariant rhythmic course progression was identified across different wind speeds and air conditions.
• This rhythmic pattern appears conserved across different animal taxa, including moths and sharks, with variations in rhythm rate.

Conclusions:

• Olfactory search behavior is underpinned by a common conceptual basis, not discrete strategies.
• A flow-invariant rhythmic progression allows search geometry to adapt automatically to local airflow conditions.
• This framework provides a unified explanation for diverse odor-guided search patterns observed in nature.