Prior to our ability to read the genetic code, studies of insect phylogeny (the historical relationships among species) relied on traditional morphological techniques. However, morphological evidence is limited and in many cases provides us with too little information to understand past evolutionary history. Modern molecular techniques have greatly expanded the data that insect biologists have available. As groups and species evolve, the genes that make species unique change, but much of the DNA code shared by common ancestors is retained. Our ability to read the DNA code allows us to better follow the shared history of insects. Thus, new information from molecular biology is leading to rearrangements of phylogenies.
Recent updates in our phylogenetic understanding of the Hymenoptera (Wasps, Ants and Bees) suggest that those groups that have the highest level of social behavior (eusociality) belong to only two closely related groups. Older phylogenies based only on morphological analysis, had suggested an alternate arrangement in which Eusociality was distributed among multiple distantly related groups. The older phylogenies suggested that eusocial behavior had evolved independently in the Hymenoptera multiple times. Insect biologists sought answers to the question, “Why did eusociality evolve so many times in the Hymenoptera, but only once in other insects?” The new phylogeny allows for a new interpretation of the evolution of eusociality. Quite possibly, eusociality evolved only once in the Hymenoptera, obviating the need for complex explanations. This upheaval in phylogenetic relationships allows for reexamination of the forces behind the evolution of social behavior.
*Brian R. Johnson, Marek L. Borowiec, Joanna C. Chiu, Ernest K. Lee, Joel Atallah and Philip S. Ward. Phylogenomics Resolves Evolutionary Relationships among Ants, Bees, and Wasps. Current Biology 23, 2058–2062, October 21, 2013.