Collaborative Research: New World Justicia s.l.: A microcosm for understanding covariation of floral traits and pollinators in a phylogenetic context

California State University-Long Beach Foundation, Long Beach CA

Investigators

Abstract

This project will investigate how flowering plants interact with animal pollinators over evolutionary time. Flowering plants dominate the majority of terrestrial ecosystems and most depend on animal pollinators to complete their lifecycle. Biologists hypothesize that the interaction with pollinators ultimately increases the number of flowering plants over time. However, important details are lacking about how this might be happening. Flower color, shape, and size are widely understood to reflect adaptation to pollinators. Yet, emerging evidence indicates that microscopic changes in floral features may also have large effects in driving new species to evolve. This project will investigate how biochemical, microscopic and macroscopic traits of flowers vary with different animal pollinators in the water-willow genus, Justicia. Researchers will determine the evolutionary relationships among Justicia species native to North, Central and South America to analyze trait data, including field-based observations of pollinator behavior. The project will train high school, undergraduate and graduate students, including members of under-represented groups and community college students, as well as a post-doctoral research associate. Researchers will provide outreach to the public about the ecological and economic importance of pollination biology through educational exhibits at the University of Colorado Boulder Museum of Natural History and Rancho Santa Ana Botanical Garden. This project will test the hypothesis that variation in morphological traits intimately involved with the reproductive success of flowering plants are inter-correlated and are associated with functional groups of animal visitors. Researchers will investigate the evolutionary history of New World Justicia (Acanthaceae; the Acanthus family), whose ca. 400 species show remarkable diversity in micro-morphological floral traits essential to reproduction, including anthers, pollen and stigmas, and support a range of vertebrate and invertebrate pollinators. Outcomes of the research will include a comprehensive phylogenetic hypothesis for New World Justicia species based on nuclear genomic data, a quantitative analysis of macro- and micro-morphological variation in relationship to pollinator type, and improved taxonomic circumscriptions for this widespread yet poorly characterized lineage. Research will facilitate the discovery and description of species new to science, build herbarium research collections, and expand ethological information about pollinating animals. Targeted fieldwork in five Neotropical countries will strengthen international collaborations among US and Latin American scientists and facilitate investigation of this species-rich lineage. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.