A stingless bee can use visual odometry to estimate both height and distance

Area of Science:

• Animal behavior
• Sensory ecology
• Insect navigation

Background:

• Bees navigate in three dimensions, primarily using vision.
• Vision-based odometry for horizontal distance is well-studied, but vertical distance remains less understood.
• Stingless bees (Meliponini) forage at diverse heights, up to 40m, necessitating effective height estimation.

Purpose of the Study:

• To investigate if stingless bees use optic flow to gauge flight height.
• To determine the primary visual field used for height estimation in stingless bees.
• To understand how optic flow influences vertical foraging behavior.

Main Methods:

• Bees were trained to forage at a specific height in a striped vertical tunnel.
• Foraging behavior was observed in novel tunnels with varying widths and optic cues.
• Optic flow experienced by bees was manipulated by altering tunnel dimensions.

Main Results:

• Stingless bees maintained trained heights in novel tunnels, indicating learned height-specific search.
• Narrower tunnels (increased optic flow) led to lower search heights; wider tunnels (decreased optic flow) led to higher search heights.
• Bees without optic cues were disoriented and searched randomly, confirming reliance on visual motion.

Conclusions:

• Stingless bees, Melipona panamica, utilize lateral optic flow to accurately gauge flight height.
• This height-gauging ability is crucial for resource competition in varied forest canopy environments.
• Optic flow processing is a key mechanism for vertical navigation in these bees.