NSF DEB-NERC: Phylogenomics and Sensory Systems Evolution in Silkmoths and Relatives

University Of Florida, Gainesville FL

Investigators

Abstract

Nearly all animals use sight and smell to sense their surroundings. It is assumed that when a species evolves to become diurnal or nocturnal, its eyes, olfactory organs, and the genes associated with these structures also evolve. However, this concept remains largely untested, because a comprehensive evolutionary tree and associated comparative data are not available. Silkmoths and relatives are some of the most conspicuous moths, and they provide an excellent opportunity to study how two potentially complementary sensory systems -- sight and smell -- have evolved. The group includes many model organisms, such as the domesticated silkmoth and tobacco hornworm, which play key roles in many areas of the biological sciences. Some silkmoths and relatives are damaging to agriculture, and they are frequently used as an educational tool because of their large size, charisma, and ability to captivate children in classrooms. Despite their role in science and education, this model group still lacks a robust estimate of evolutionary relationships. With collaborative research teams in the United States and the United Kingdom, this project will assemble an extensive genetic dataset and reconstruct a robust evolutionary tree for the group. Two postdoctoral researchers, two graduates students, several undergraduates, and dozens of elementary, middle and high school students will be trained, including many students from under-represented groups. This study will produce a comprehensive phylogeny of a model insect group, the silkmoths and relatives (Lepidoptera: Bombycoidea) and use it to study the evolution of two principal sensory systems: vision and olfaction. The project will develop a US-UK collaborative partnership across five institutions to initially generate a target capture-based backbone phylogeny based on 700 genetic loci and 1000 species of Bombycoidea. Scanning electron microscopy and 3D Micro-computed Tomography scanning will then be used to quantify sensory morphology of two key organs (eye and antenna) that are central to insect vision and olfaction. The molecular evolution of vision and olfactory gene sequences isolated from sensory organ transcriptomes will be analyzed to test for evidence of selection between related diurnal and nocturnal species. Gene sequences will be isolated from frozen and museum specimens using new methodologies, thereby making this tool useful to the broader community of scientists.