Sergio Rasmann

Functional ecology

See also naturethinking.com

Synopsis of our research

Nearly three quarters of the world's macroscopic biodiversity is tied up in the look between plants, herbivores, predators, and decomposers. In this context, the study of trophic interactions, involving plants, herbivores, and their predators or parasitoids represents a frontier in ecology, and this knowledge can be integrated in environmentally sound agricultural pest managements.
Over the last half century, complementary theories and hypotheses have been developed to try to explain the extraordinary variation in plant defensive strategies against herbivores, and, thanks to interdisciplinary interaction between ecologist, behaviorists, physiologist, and chemists, it has given rise to the body of work, collectively known as "plant defense theory". Nowadays, advances in community phylogenetic and metabolomic analysis are the key components for refining plant defense theories at a novel frontier.
In (1964), Ehrlich and Raven, in their classic treatise defining "coevolution", suggested that community evolution was "one of the still least understood aspects of population biology". Remarkably, they argued that it was time for the melding of community ecology, biochemical analysis, and macroevolutionary studies. Impressively, only in the last few years, or perhaps only in the coming decade, will we be able to fully tackle this goal.

Below is the outline of our contributions to the new coevolutionary synthesis:

1. Mechanistic chemical ecology occurs in a community context. We are interested in above- and below-ground tritrophic interactions, and the chemical singnals mediating such interactions.
2. Comparative biology is moving from description to experimental approaches
   We use phylogenetic, quantitative genetic and phyto-chemical analyses, coupled with behavioral assays to study the ecological importance and the evolution of chemical defenses in diverse plant-herbivore systems, such as the American milkweed plants (Asclepias spp.), or the Alpine Cardamine spp.
3. The same factors which mediate ecological interactions may play a role in adaptation and diversification.
   Darwins paradox of closely related species being phenotypically similar (thus more likely to compete for the same resources), but distinct enough to co-occur in the same habitat, is still a tough nut to crack. We can study ecology mechanistically and diversification descriptively. Here the goal is to understand how they come together. To understand a community of coexisting plants and arthropods will thus need the knowledge of phylogenetic relatedness of plants and animals, and the mechanisms shaping their relationships. We are currently studying the effects of radiation and adaptation into high altitudes on plant herbivore interactions and plant defenses.

Teaching activities

• Fundamentals in ecology
• Biomes and biosphere
• From genes to ecosystems
• Methods in plant ecology

Publications