The Evolution and Development of Polyphenisms

offered Fall 2008

Polyphenisms, where an individual can express one of two or more alternative, discrete phenotypes, are systems well-suited to study the ecological conditions that favor the maintenance of phenotypic variation within a single population. In particular, polyphenisms can be used as powerful tools for studying the relationships between genotypic and phenotypic variation, performance, and fitness. They can also be used to study the proximate mechanisms that underlie phenotype development, and the role of developmental plasticity in morphological diversification.

In this seminar series, we covered the evolution and development of polyphenisms in selected biological systems. We focused on exploring various polyphenisms after investing a few meetings in covering the theory of the conditions that favor the evolution and maintenance of polyphenisms.

Format

Students worked in teams of two, presenting some of what is known about a given polyphenism each week. Students were free to focus narrowly on a particular system or to take a more broad approach, discussing ecologically similar polyphenisms in a comparative context. In addition to covering the evolutionary ecology of a given polyphenism, it was expected that presentations covered the physiological, developmental, and genetic mechanisms underlying morph expression. Presentations lasted 45 mins to one hour, and students divided their time such that each contributed to the presentation. A short (~300 word) abstract of the talk and reference list was distributed to the group the day before the presentations.