Hybrid Viability: An analysis of Drosophila hybrid competition and mating success amongst its parental species

The topic of hybrid offspring viability and mating preference between the two parental species of Drosophila athabasca (West Northern) and Drosophila mahican (Eastern A) is a still largely unexplored avenue of study. While the two aforementioned parental Drosophila species exist in distinct geographical regions across North America, they occupy a sympatric zone in the North East. Due to the absence of hybrid offspring in nature and the high levels of sexual isolation between these two parental species, it is necessary to establish if, and how hybrid offspring suffer in nature. By utilizing no choice mating systems involving audio playback of the opposing species male courtship song, this study was able to produce hybrid offspring derived from females of either of the two aforementioned species thereby bypassing the strong levels of sexual isolation between the two in order to form hybrids. These hybrids, along with their two pure (parental) species were placed within bottled micro-environments in equivalent proportions, in varying combinations. By randomly sampling the F1 generation offspring from within these bottled environments, extracting DNA from each of the selected files, and by sequencing the DNA with the knowledge of species-specific polymorphic sites, each respective selected F1 fly was successfully identified according to a species or hybrid population. Statistical analysis of the selected genotypic frequencies against proposed mating models of varying degrees of population inbreeding and outcrossing provided evidence for hybrid suffering in competitive experimental bottles, further evidence of sexual isolation between the parental species, and evidence of high hybrid fecundity