Thermal avoidance during flight in the locust Locusta migratoria

Area of Science:

• Insect behavior
• Sensory biology
• Locomotion

Background:

• Locusts display complex behaviors for navigation and survival.
• Understanding sensory mechanisms guiding flight maneuvers is crucial for insect flight research.

Purpose of the Study:

• To investigate thermal avoidance behaviors in tethered flying locusts.
• To identify the sensory pathways involved in detecting and responding to heat stimuli.

Main Methods:

• High-speed cinematography to analyze body posture and wing movements.
• Electromyography to record muscle activity during thermal stimulation.
• Ablation experiments to test the role of specific sensory organs.

Main Results:

• Locusts performed abdomen and hindleg ruddering in response to a heat source.
• Asymmetrical forewing depression and altered muscle activity (M97) were observed.
• Wingbeat frequency increased, while hindwing movements remained symmetrical.
• Antennal flagella ablation did not eliminate thermal avoidance.

Conclusions:

• Thermal avoidance in locusts is mediated by infrared sensitivity.
• This sensitivity is independent of compound eyes, ocelli, and antennal flagella.
• Novel motor control mechanisms are involved in locust thermal avoidance maneuvers.