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A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants
Published on: October 12, 2018
Antimicrobial defences increase with sociality in bees.
Adam Stow1, David Briscoe, Michael Gillings
1Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia. astow@rna.bio.mq.edu.au
Biology Letters
|May 17, 2007
Summary
Social insects evolved stronger antimicrobial defenses as they became more social. This research shows increased group size and relatedness correlate with enhanced antimicrobial compounds, crucial for disease control in social evolution.
Area of Science:
- Evolutionary biology
- Immunology
- Insect social behavior
Background:
- Microbial pathogens are ancient selective agents, driving antimicrobial defense evolution across the animal kingdom.
- Social insects, particularly eusocial Hymenoptera, face high disease transmission risks due to crowding and genetic factors.
- Antimicrobial secretions serve as crucial primary barriers against infection in social insects.
Purpose of the Study:
- To investigate if increased disease risk associated with sociality drives selection for stronger antimicrobial secretions in bees.
- To test the hypothesis that antimicrobial strength is correlated with the evolution of sociality.
Main Methods:
- Comparative analysis of antimicrobial compound strength across bee species with varying social structures.
- Correlation analysis between social parameters (group size, genetic relatedness) and antimicrobial efficacy.
Main Results:
- A strong positive correlation exists between group size, genetic relatedness, and antimicrobial strength in bees.
- Antimicrobial compounds in primitive semi-social bee species were significantly stronger than those in solitary species.
- This suggests a critical threshold for disease control was necessary for social evolution.
Conclusions:
- Selection pressure from microbial pathogens was a key driver in the evolution of sociality in bees.
- The development of potent, front-line antimicrobial defenses was essential for overcoming disease challenges in social insect evolution.
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