Scientists Find New Colony Structure of Fire Ants Evolved in One Species Before Spreading to Others
Published:14 Mar.2022 Source:Queen Mary University of London
Red fire ants originally had only colonies with one queen. The team previously discovered that about one million years ago, a new social form evolved where colonies could have dozens of queens. A particular version of a large section of chromosome, named the "social supergene," includes the genetic information necessary to make workers accept more than one queen. The new research, published today in Nature Communications, analysed the entire genomes or instruction sets of 365 male fire ants to examine the evolution of the social supergene, and found that the same version of this chromosome is present in multiple fire ant species.
Transfer of large amounts of genetic information across species is rare because of genetic incompatibilities. However, in this case, the advantages of having multiple queens overrode the incompatibilities, and the genetic material repeatedly spread to other species from the one source species in which this new social form evolved. The multiple-queen social form has advantages in several situations. For example, a multiple-queen colony has more workers and thus can outcompete a colony with only one queen. Furthermore, if there is a flood, a colony with multiple queens is less likely to become queenless.