Interplay between genes and the environment has been pondered at least since the phrase nature versus nurture was coined in the mid-1800s.
But until the arrival of modern genomic sequencing tools, it was hard to measure the extent that the environment had on a species genetic makeup.
Now, researchers with the Virginia Bioinformatics Institute at Virginia Tech studying fruit flies that live on opposite slopes of a unique natural environment known as Evolution Canyon show that even with migration, cross-breeding, and sometimes the obliteration of the populations, the driving force in the gene pool is largely the environment.
The discovery in this weeks Proceedings of the National Academy of Sciences shows that the animals genetically adapt depending on whether they live on the drier, hotter side of the canyon, or the more humid, cooler side.
Despite complicating factors, such as likely gene flow between the two populations and changing demographics, the difference in the microclimate in this canyon apparently is so pervasive that it is sufficient to drive the genetic differences, said Pawel Michalak, an associate professor at the Virginia Bioinformatics Institute. We dont have many examples of rapid environmental adaptation to stressful conditions from the field. We can simulate such conditions in a lab, but it is valuable to observe this actually happening in a natural system.
The two slopes of Evolution Canyon, which is located at Mount Carmel, Israel, are little more than two football fields apart at their bases, but the south-facing slope is tropical and may receive eight times as much sun, while the north-facing slope is more like a European forest.
Knowledge that climatic and environmental factors seem to exert a significant effect on the fruit-fly genome in spite of migration or repopulations adds to current understanding of the biodiversity, resilience, and ability of a species to adapt to rapid climate change.