Endoreduplication underlies body size variation in monomorphic ants

Area of Science:

• Evolutionary biology
• Developmental biology
• Entomology

Background:

• Morphological variation in ants is crucial for labor division.
• Cellular mechanisms of worker size variation are understudied.
• Endoreduplication is a cellular process with potential for morphological diversity.

Purpose of the Study:

• Investigate endoreduplication's role in body size variation in monomorphic ants.
• Determine if body size correlates with endoreduplication levels.
• Compare patterns in monomorphic species to those in polymorphic species.

Main Methods:

• Assessed body size and nuclear DNA content (C-value) in workers of three monomorphic ant species.
• Utilized linear mixed-effects models (LMM) for statistical analysis.
• Examined body-part specificity of C-value levels.

Main Results:

• Individual worker size positively correlated with nuclear DNA content (C-value).
• This correlation was significant in overall and species-specific analyses.
• C-value levels were highest in the abdomen, showing body-part specificity.

Conclusions:

• Endoreduplication contributes to body size variation in both polymorphic and monomorphic ants.
• This suggests endoreduplication is an ancient and widespread mechanism in ants.
• Endoreduplication may have provided a developmental basis for the evolution of ant polymorphism.