Our goal was to test the hypothesis that the fruit fly species (Diptera: Tephritidae), S. longipennis is actually composed of several morphologically distinct species. Specimens were identified morphologically using the following characteristics: wing pattern, scutellar markings, and notal stripes. Using these characters we identified three species in our sequenced sample: S. perfecta (N=7), S. vittigera (N=21), and S. longipennis (N=11). One of those species, S. vittigera, is currently treated as a synonym of S. longipennis. To test the hypothesis that morphological characters effectively reveal species, we extracted DNA, and amplified and sequenced the mitochondrial cytochrome oxidase subunit I gene. We then used PAUP to analyze the sequence data to find out if the most parsimonious reconstruction based on molecular data reveals the number of taxa suggested by some morphologists. We found that the molecular data supports two separate taxa of S. longipennis and S. vittigera.
Heather Axen, ’06 Golden, CO
Major: Biochemistry and Molecular Biology
Jessica Harrison, ’05
Sponsor: Marty Condon