Katydids are a well-recognized family of insects, yet surprisingly little is known about the historical relationships between the 6500 known species. Also, little is known about the evolution of their unique morphological features such as the sound reception organs on their front legs (commonly referred to as ears) and the origins of their defenses against predation: leaf-like wings, bright warning coloration, and camouflage. This project will result in the first phylogenetic analysis of katydids and provide the groundwork for understanding the development of their unique ears and methods of camouflage.
DNA data generated during this project will be used to develop two formal lab exercises for undergraduate students. During the duration of funding, these exercises will provide over 1,000 undergraduate students with hands-on training in how to align DNA sequences, reconstruct phylogenetic trees, map characters on topologies, and how to use phylogenetics to answer fundamental questions in science. This research will also provide minority undergraduate students with direct mentorship on specific projects. These students will generate data for a subset of the project, analyze results, present their findings at national meetings, and be senior author on a publication coming from this work.
Katydids have long been popular to biologists and the general public due to their unique leaf-like wings and their acoustic signaling (songs) that are a prevalent sound at night throughout the world. Despite their popularity, little was known about the evolution of their unique morphology, acoustic signaling, or patterns of genealogical (phylogenetic) relationships. This study resulted in the first robust and comprehensive phylogenetic hypothesis for these insects, providing critical insights into the relationships among major katydid groups. Prior to our research, the methods for discerning leaf-like from non leaf-like wings were arbitrary and subjective. We developed a simple and repeatable metric for identifying leaf-like wings, and learned that these wings evolved multiple times during the evolution of these insects. Our research established the timing of katydid diversification and their biogeographic history. This work is laying the foundation for understanding the evolution of the incredible diversity within katydids, and an understanding of why they sing the way they do. This work will result in a total of 7 publications that formed the dissertation work of the Co-PI. This research directly involved five undergraduate students who gained significant research experiences working on various aspects of this project. Three of these students were individuals who came from groups traditionally underrepresented in the sciences. Four of these students have gone on to pursue graduate work in the sciences based largely on this research experience. Moreover, the data and specimens that resulted from this work were used in undergraduate labs to study various aspects of evolution. Over the course of funding, more than 400 students learned basic principles in biology by studying katydid evolution.
