Researchers from the University of Cambridge have made a groundbreaking discovery, revealing the ability to induce virgin births in female fruit flies that typically reproduce sexually. The findings, published in the peer-reviewed Current Biology journal on Friday, indicate that this capacity can be inherited across generations, suggesting a mechanism that helps the species survive through a cycle of virgin births.
The scientists achieved this feat by genetically manipulating female fruit flies of the species Drosophila melanogaster, enabling them to produce offspring without engaging in sexual reproduction with male counterparts. The study further demonstrated that the phenomenon of virgin births can be transmitted through successive generations of female fruit flies.
Lead author and University of Cambridge researcher, Alexis Sperling, expressed excitement about the groundbreaking achievement, stating that they are the first to engineer virgin births in an animal. The researchers discovered that a virgin fly could produce an embryo that develops into adulthood and subsequently repeat the process.
To achieve this outcome, the team sequenced the genomes of two strains of a different fruit fly species, Drosophila mercatorum. One strain reproduced sexually with the involvement of males, while the other reproduced solely through virgin births. By identifying the genes that played a role in the reproductive process of the virgin birth strain, the scientists genetically altered the corresponding genes in the model fruit fly, drosophila melanogaster, which ultimately led to virgin births.
In the genetically manipulated flies, the females waited for approximately 40 days (half their lifespan) to find a male partner. When unsuccessful, they proceeded to engage in virgin births. The study revealed that in the second generation of female flies with the ability for virgin births, only one to two percent of the offspring were produced when no male flies were present. In the presence of male flies, females mated and reproduced sexually.
The offspring resulting from virgin births are not exact clones of their mothers but exhibit genetic similarities and are consistently female. The research involved more than 220,000 virgin fruit flies and took six years to complete.
The significance of this discovery lies in the rarity of virgin births in animals that primarily reproduce sexually. Typically, virgin births occur in isolated individuals, but this study demonstrates that the ability can be passed down to subsequent generations, suggesting an adaptive mechanism in the species. The researchers speculate that if selection pressure for virgin births persists in insect pests, they may eventually reproduce exclusively through this method.