While the vast majority of animals produce offspring through sexual intercourse, others have developed more unconventional methods. Researchers from Université Libre de Bruxelles (ULB), in partnership with colleagues from CSIC Seville in Spain, have taken a closer look at one example of a more unusual reproductive mechanism.
Led by Serge Aron from the Behavioral and Evolutionary Ecology Service at ULB, the scientists studied hybridogenic reproduction on a community scale among the desert ant species, Cataglyphis hispanica
Hybridogenic reproduction is practiced by some species of fish, frogs and stick insects. Mating takes place between male and female individuals of different species or divergent genetic lineages, producing hybrid offspring with genes from both.
However, the genetic material from the father is discarded when ova (eggs) are formed in the female young. This means that only the maternal genome is passed on to the next generation, potentially in combination with new genetic material from a mate.
Desert ants, like other members of the order Hymenoptera
including bees and wasps, live in social groups with two distinct types of female; a select few are fertile queens while the majority are sterile workers.
Through genetic analysis the researchers demonstrated that, among the ant community, two separate and interdependent genetic lineages exist. Sexual reproduction between these lines produces those individuals that will make up the sterile workforce, whereas the queen asexually reproduces – or clones herself – to create fertile future queens. Male ants also develop from unfertilized eggs, sharing their mother’s genetic material.
The team believe that such a strategy, whereby sexual reproduction is used to supply workers and asexual reproduction for the continuation of the species, has comprehensive implications for the evolutionary process.
The paper is due to appear in the journal Current Biology