Drosophila glue protects from predation

Area of Science:

• Evolutionary Biology
• Animal Behavior
• Entomology

Background:

• Pupa adhesion is a common trait in terrestrial insects, evolved to secure the pupa in a safe location.
• Predator avoidance is a primary driver for the evolution of pupa adhesion in insects.
• The specific role of pupa adhesion in preventing predator-induced detachment in Drosophila remains underexplored.

Purpose of the Study:

• To investigate if pupa adhesion in Drosophila serves to prevent detachment by potential predators.
• To compare the effectiveness of pupa adhesion in different Drosophila species.
• To analyze the impact of pupa adhesion on predation rates by ants.

Main Methods:

• Measured pupa adhesion strength across different Drosophila species from the same geographic area.
• Conducted field assays comparing the site retention of attached versus manually detached pupae over 3 days.
• Performed laboratory assays to assess predation efficiency of ants on attached versus detached Drosophila pupae.

Main Results:

• Significant variation in pupa adhesion was observed among Drosophila species, linked to diverse glue production strategies.
• Attached pupae showed 30% greater site retention in field trials compared to detached pupae, indicating reduced predation.
• Laboratory experiments revealed that ants were less efficient at preying on attached pupae, requiring more ants and consuming them onsite.

Conclusions:

• Drosophila pupa adhesion plays a critical role in preventing removal by predators, thereby enhancing survival.
• The ability to resist detachment by predators is a key adaptive function of pupa adhesion in Drosophila.
• Variations in adhesion strategies among species may reflect differential selective pressures from predators.