New study challenges decades-old genetic explanation for insect eusociality

Scientists at Arizona State University assembled social and genetic data for tens of thousands of insects and mapped them onto two large phylogenetic trees. Initial results seemed to support the long-standing idea that haplodiploidy promotes eusocial colonies, but a deeper statistical review revealed that this pattern is almost entirely confined to the aculeate Hymenoptera, which includes ants, bees and stinging wasps.

After removing the influence of this single branch, haplodiploid insects outside the group showed eusocial emergence comparable to diploid insects. The study, published in Current Biology, argues that other lineage-specific traits—such as stingers, specialized nesting, and life-history factors—likely drive the repeated evolution of sophisticated insect societies. This work represents one of the most extensive empirical tests of a foundational evolutionary theory.