Relaxed selection underlies genome erosion in socially parasitic ant species

Research output: Contribution to journalJournal articleResearchpeer-review


  • Lukas Schrader
  • Hailin Pan
  • Martin Bollazzi
  • Morten Schiøtt
  • Fredrick J. Larabee
  • Xupeng Bi
  • Yuan Deng
  • Zhang, Guojie
  • Boomsma, Koos
  • Christian Rabeling

Inquiline ants are highly specialized and obligate social parasites that infiltrate and exploit colonies of closely related species. They have evolved many times convergently, are often evolutionarily young lineages, and are almost invariably rare. Focusing on the leaf-cutting ant genus Acromyrmex, we compared genomes of three inquiline social parasites with their free-living, closely-related hosts. The social parasite genomes show distinct signatures of erosion compared to the host lineages, as a consequence of relaxed selective constraints on traits associated with cooperative ant colony life and of inquilines having very small effective population sizes. We find parallel gene losses, particularly in olfactory receptors, consistent with inquiline species having highly reduced social behavioral repertoires. Many of the genomic changes that we uncover resemble those observed in the genomes of obligate non-social parasites and intracellular endosymbionts that branched off into highly specialized, host-dependent niches.

Original languageEnglish
Article number2918
JournalNature Communications
Number of pages13
Publication statusPublished - 2021

ID: 272572682