Olsen, Lindsey; Frandsen, Paul (Brigham Young University)
Faculty Advisor: Frandsen, Paul (Life Science, Plant and Wildlife)
Trichoptera (caddisflies) have evolved to become the most diverse, exclusively aquatic insects, yet many of the genomic changes that contribute to Trichoptera's the success of this order of insects are still unknown. Trichoptera and Lepidoptera (moths and butterflies) are reciprocally monophyletic meaning that they both share their most recent common ancestor. Despite being closely related, Trichoptera have evolved into the most diverse, exclusively aquatic insects, whereas, Lepidoptera have evolved to become a diverse, almost exclusively terrestrial insect (Holzenthal et al. 2007). Trichoptera and Lepidoptera are the subjects of scientific inquiry because they are both capable of spinning silk. Trichoptera produce silk as larvae and use it to make cases or fixed retreats. Trichoptera silk is of particular interest because its properties allow for it to be an underwater adhesive. While other research has focused primarily on the evolution of Trichoptera silk, little research has been done to identify the evolutionary innovations that allowed Trichoptera to adapt and diversify in an aquatic environment. Our research focuses on identifying the genomic basis of their evolutionary innovations. We report the genome annotation of four newly sequenced Trichoptera species Hesperophylax magnus, Parapsyche elsis, Philanisus plebeius, and Rhyacophila brunnea. These annotations will reveal levels of homozygosity, conserved elements, and gene duplications. We then conducted a genome-wide search for gene family expansions and retractions using CAFE, in order to identify genomic regions that could contribute to Trichoptera's unique qualities and evolutionary history.
Holzenthal R. W., R. J. Blahnik, A. L. Prather, and K. M. Kjer, 2007 Order Trichoptera Kirby, 1813 (Insecta), Caddisflies*. Zootaxa 1668: 639—698. https://doi.org/10.11646/zootaxa.1668.1.29