Plant-feeding insects are a ubiquitous feature of terrestrial life. It follows that understanding the evolution of insect herbivory and its diversity is fundamental to understanding the evolution of terrestrial ecosystems. During my Ph. D. study, I found phylogenetic conservatism in the feeding mode (internal vs. external feeding) of Yponomeutoidea, one of the primitive lepidopteran superfamilies, as well as in their diet breadth and in the growth form and taxonomic affinities of host plants they used. In spite of their importance in terrestrial ecosystems, the evolutionary history of Lepidoptera has been poorly known. This mostly is attributable to their poor fossil record. My Ph. D. study provided better understanding to the lepidopteran fossils. Fossils are an essential resource in divergence time estimation using molecular clock methods. Once reliably resolved, dating data can be used in tracing the evolutionary history of Lepidoptera/plant associations. I introduce my works to take such advantages from fossils and phylogenetic studies.

• Jae-Cheon Sohn(Institute of Littoral Environment, Mokpo National University)
• Sei-Woong Choi(Institute of Littoral Environment, Mokpo National University, Department of Environmental Education, Mokpo National University)