Electric field detection as floral cue in hoverfly pollination

Area of Science:

• Entomology
• Sensory Ecology
• Bioelectricity

Background:

• Pollinators use visual, olfactory, and thermal cues to locate flowers.
• The role of floral electric fields in pollinator interactions is largely unexplored.
• Hoverflies are important dipteran pollinators with diverse sensory capabilities.

Purpose of the Study:

• To investigate the capacity of hoverflies (Eristalis tenax and Cheilosia albipila) to detect floral electric fields.
• To understand how electrical interactions between hoverflies and flowers influence nectar detection and pollination.
• To identify the sensory mechanisms underlying electroreception in hoverflies.

Main Methods:

• Observational studies on hoverfly-flower electrical interactions.
• Analysis of charge acquisition by hoverflies.
• Electrophysiological recordings from hoverfly antennae.
• Investigation of thoracic hair function in charge polarity.

Main Results:

• Hoverflies exhibit electro-mechanosensory capabilities, similar to bumblebees.
• Rapid floral electric field variations correlate with nectar presence and influence hoverfly visitation.
• Thoracic hairs are implicated in determining hoverfly charge polarity.
• Antennal electrophysiology did not show neural sensitivity to electric fields.

Conclusions:

• Hoverflies can detect floral electric fields, contributing to nectar identification.
• Mechanosensory hairs on hoverfly thoraxes are likely the primary electroreceptive organs.
• This study reveals a novel sensory modality for dipteran pollinators, expanding our understanding of plant-pollinator interactions.