New dimensions of tropical diversity: an inordinate fondness for insect molecules, taxa, and trophic interactions

• Tropical insect diversity discoveries are not matching the pace of deforestation.
• Population genomic approaches link measures of diversity across trophic levels.
• Advances in chemistry allow for accurate quantification of phytochemical diversity.
• Diversity hypotheses can be tested with genomics, metabolomics, and network models.

Most known insect species are involved in chemically mediated plant–insect multi-trophic interactions, and recent syntheses point to a substantial gap in our understanding of trophic interaction diversity, especially in the tropics. One approach to filling this gap is to examine relationships between genomic, metabolomic, taxonomic, and trophic interaction diversity via quantifying and comparing these dimensions of biodiversity at multiple scales. Innovative approaches to research on the origins and maintenance of tropical insect diversity should merge traditional approaches to natural history and taxonomy with modern measures of interaction diversity, genetic variation, and phytochemical diversity. These approaches will elucidate relationships between plant chemistry, specialization, climate, and different dimensions of biodiversity.