Meeting Abstract
How do major transitions in development occur, and what are their evolutionary consequences? Large-scale evolutionary changes, from molecular diversification to speciation, are initially constrained by early developmental program. To understand how genetic variation contributes to variation in development, I use an emerging model system: the polychaete Streblospio benedicti. This species is ideal because it produces two distinct offspring types that differ in egg size, early development, and larval morphology. Using genetic crosses, I identify quantitative trait loci (QTLs) for reproductive traits. By extending crosses to the F3 generation, I can map loci associated with egg size and distinguish maternal effects. To contextualize this marker information, I am constructing both the genetic map and the S. benedicti genome assembly. I identify regions that differ between larval morphs, and uncover how the dimorphic developmental program is determined on a whole-genome level.
