Research project Evolving modularity in the adaptations of phytophagous insects to host plants
The project aims to improve our understanding of how insect-plant and other parasite-host species associations evolve.
Butterflies are the main study organisms. This is done through a combination of studies on gene expression on different host plants, larval growth experiments in the laboratory and phylogenetic investigations.
Project description
Understanding the adaptations of phytophagous insects to their host plants is a crucial component in understanding the ecological and evolutionary dynamics of their host repertoires, including aspects such as conservatism, specialization, colonizations of novel hosts, and phylogenetic recurrence of ancestral hosts that have been lost. Previous research on butterflies in the tribe Nymphalini has provided a wealth of information on the patterns of such dynamics, but there is a lack of understanding of the causality behind the patterns observed, and several unanswered questions:
- Why is host plant use often very conservative, in that related insects feed on related plants, often over millions of years?
- Why are insects often specialized on a given plant group, even though this means missing out on many other potential food sources?
- When and how is it possible to break this pattern and colonize novel plants, and when does this lead to a broadening of the host repertoire or to a complete host shift?
- How is it apparently possible for an insect to relatively easily re-colonize a host that they have stopped using, sometimes after very long time spans?
We are addressing this knowledge gap in the current project, which is based on the idea that adaptations to specific hosts can best be understood as “modules” of co-expressed genes and the corresponding phenotypes – in particular larval performance. We test hypotheses regarding the importance of time since first colonization and trade-offs among host plants for observed modularity, as well as hypotheses regarding links between modularity and likelihood of specialization, conservatism, and recurrence of host plants. This is done in a context of known phylogenetic relationships, so phylogenetic investigations are also an important part of the project.
Alongside comparative genomics on a phylogenetically informed set of butterfly species, We are using growth experiments for reciprocal illumination of results, in particular as they pertain to trade-offs between using different plants as hosts. The similarities observed between insect-plant and parasite-host interactions suggest that insights from the former would to a large extent apply also to the latter, extending the potential relevance of the project.
Project members
Project managers
Sören Nylin
Professor
Members
Niklas Janz
Professor
Maria de la Paz Celorio Mancera
Research Engineer
Rachel Steward
Postdoc
Katharina Schneider
PhD student