The Genetic Basis of Pigmentary and Structural Color Variation in Gilbert's Skink and other Lizards
Ian Wang, Professor
Environmental Science, Policy and Management
Closed. This professor is continuing with Fall 2024 apprentices on this project; no new apprentices needed for Spring 2025.
This research investigates the genetic basis of lizard coloration, which is an ideal trait for studying evolution. Animal coloration is divided into pigments and structural colors. Pigments, often red and yellow, are small particles that directly absorb and reflect light of different colors. Structural colors, often blue, are caused by the interaction of light reflecting off different cellular layers. Pigment colors often have simple genetic control mechanisms, but the genetic basis of structural colors in vertebrates is only beginning to be understood. This research will leverage unique species of lizards and snakes that independently evolved variation in blue structural vs. red or yellow pigmentary color to unlock their genetic basis.
The primary objectives of this research are to 1) understand the genomic basis of structural color and associated regulatory and cellular changes, and 2) test for conserved changes across increasing phylogenetic scales. This research will first focus on Plestiodon gilberti (Gilbert's Skink) in California which display red pigmentary and blue structural tail color variation. We will compare genomes (DNA) to pinpoint the genomic regions that underlie color variation, then investigate associated gene expression changes (RNA) and corresponding cellular anatomy of color-producing cells. As individuals age, they lose their color and converge on the same adult phenotype, which we will leverage to assess if ontogenetic color change is controlled by the same regulatory pathways as polymorphism. Next, we will investigate if the same genomic regions underlie structural color polymorphism using whole genome sequencing on other lizards and snakes around the world. Finally, we will compare genomes in public databases to test if candidate loci from genomic sequencing predict the presence or absence of bright structural colors.
Role: We are recruiting 1-2 undergraduate students to assist with several aspects of this project: (1) Catching lizards in the field and taking tissue samples and other data. Fieldwork will primarily be in California and may involve occasional multi-day trips (1-2 times per semester). (2) Conducting molecular analyses in the genetics lab. This may include extracting DNA and RNA from preserved lizard tissues, assessing DNA quality, and preparing samples for sequencing. (3) Computational analyses, which may include bioinformatics on genetic data and/or comparative analyses in R. Highly motivated students may have the opportunity to conduct independent field projects. Students will gain skills that are transferrable to other careers, such as wildlife biology and biotech.
Qualifications: The student should have an interest and some background in organismal biology (please list any courses that included a field component in your application). The student should have some interest in conducting fieldwork. Coursework and previous experience with genetics and DNA sequencing is desirable but not required. Sophomore or Junior year students will be prioritized with the hope being they would like to participate in future semesters.
Day-to-day supervisor for this project: Ben Karin, Post-Doc
Hours: to be negotiated
Related website: https://www.benkarin.com/
Environmental Issues Biological & Health Sciences