We characterized the chemical profile of one-third of the species of tropical rainforest trees in the genus Inga (~ 100, Fabaceae) using UPLC-MS based metabolomics and applied phylogenetic comparative methods to understand the mode of chemical evolution.
We show: 1) Each Inga species contain structurally unrelated compounds and high levels of phytochemical diversity. 2) Closely related species have divergent chemical profiles, with individual compounds, compound classes and chemical profiles showing little to no phylogenetic signal. 3) At the evolutionary time scale, a species’ chemical profile shows a signature of divergent adaptation. At the ecological time scale, sympatric species were the most divergent, implying it is also advantageous to maintain a unique chemical profile from community members. 4) Finally, we integrate these patterns with a model for how chemical diversity evolves.
Taken together, these results show that phytochemical diversity and divergence are fundamental to the ecology and evolution of plants.
- chemical defense
- phytochemical diversity
- plant specialized metabolism
- secondary metabolism