Related Experiment Video
Updated: Jun 23, 2026

Embryo Injections for CRISPR-Mediated Mutagenesis in the Ant Harpegnathos saltator
Published on: February 9, 2021
Rapid evolution of immune proteins in social insects
Lumi Viljakainen1, Jay D Evans, Martin Hasselmann
1Department of Biology, University of Oulu, Finland. lumi.viljakainen@oulu.fi
Abstract:
The existence of behavioral traits connected to defense against pathogens manifests the importance of pathogens in the evolution of social insects. However, very little is known about how pathogen pressure has affected the molecular evolution of genes involved in their innate immune system. We have studied the sequence evolution of several immune genes in ants and honeybees. The results show high rates of evolution in both ants and honeybees as measured by the ratio of amino acid changes to silent nucleotide changes, the ratio being clearly higher than in Drosophila immune genes or in nonimmunity genes of bees. This conforms to our expectations based on high pathogen pressure in social insects. The codon-based likelihood method found clear evidence of positive selection only in one ant gene, even though positive selection has earlier been found in both ant and termite immune genes. There is now indication that selection on the amino acid composition of the immune-related genes has been an important part in the fight against pathogens by social insects. However, we cannot distinguish in all the cases whether the high observed d(N)/d(S) ratio results from positive selection within a restricted part of the studied genes or from relaxation of purifying selection associated with effective measures of behaviorally based colony-level defenses.
Related Concept Videos
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Gene Evolution - Fast or Slow?
In contrast, regions which code...
Evolution of New Traits in Microbes
Viral Mutations
Transduction
Evolutionary Processes in Microbes

