Organisms develop into complex, multicellular organisms in part by turning on genes early in the developing egg and embryo that serve to instruct individual cells as to their identities. Aphids are a type of insect that reproduce either sexually or asexually depending on the season (e.g., summer versus fall) and the process by which the progeny of sexual versus asexual aphids develop is very different. Sexual aphids lay eggs on leaves while asexual aphids give live birth and this results in dramatic differences in how the daughter eggs and embryos of these aphids develop (amount of yolk, number and size of cells, timing of events, etc.). This represents an extreme case of developmental plasticity, in which development has been altered due to changes in the environment with no change in the genome. The PI, his collaborators, and students have used molecular tools to detect differences in the expression of genes involved in key steps in the development of the progeny of sexual versus asexual aphids. The goal of this work is to continue to characterize the extent of these differences and these efforts should deepen our understanding of how early development can be dramatically altered without changing the genome. The work will take place at a predominantly undergraduate institution and thus an additional objective is to train undergraduate students in the design and execution of hypothesis-driven experimentation and data analysis within the discipline of developmental biology.
