Research areas

Research interests

Two basic questions underlie much of my research, detailed below with select examples of my work.

1. How are organisms related to one another in time, and what can this history, reflected in robust phylogenetic hypotheses, tell us about plant evolution and ecology?

2. What are the morphological, environmental, and genetic corollaries of transitions between biotic and abiotic pollination?

Phylogenomics and bioinformatics

The increasing availability of next-generation sequencing (NGS) has revolutionized molecular phylogenetics and the field of systematics in general. I use target-enrichment (HybSeq), a cost-effective and high-throughput method for sequencing hundreds of targeted genes, in my phylogenetic work and am beginning to explore its utility for targeted functional genomics as well. I have focused in particular on "herbarium phylogenomics"—the appliation of target enrichment to degraded DNA extracted from old museum specimens, optimizing protocols to extract sequences from specimens over 100 years old. Current projects involve serveral genera of the Moraceae as well as tropical Asian Apocynaceae.

Pollination biology and the evolution of floral scent

Most flowering plants rely on animal pollinators. Wind pollination, which has evolved repeatedly in flowering plants, was long considered an evolutionary dead end that could seldom give rise to derived animal pollination. Wind pollination is typically accompanied by a loss of showy floral morphologies and is characterized by loose catkins of reduced, inconspicuous flowers, absence of nectar and scent, and dry powdery pollen. A number of studies have recently documented animal pollination in largely wind-pollinated lineages, however. They retain the inconspicuous reduced flowers associated with wind pollination but evolve a stiff, fragrant, condensed inflorescence (flower head) on which the reduced flowers are tightly packed together, often serving as a brood site for tiny insect. My research uses phylogenetics, field experiments, and analysis of floral scent to expore transitions between pollination mechanisms.

Systematics of the mulberry family

The mulberry family (Moraceae) has about 38 genera and about 1,200 species. Representatives can be found almost worldwide, from tropical rainforests to temperate and even arid regions. Notable species include mulberries (Morus) , which provide food for humans and silkworms, paper mulberry (Broussonetia), which is used for fiber, as well as breadfruit (Artocarpus altilis), jackfruit (Artocarpus heterophyllus) and other underutilized tree crops and wild relatives. Figs (Ficus, about 800 species) are keystone species in many tropical forests, supporting a wide range of wildlife. Life forms range from trees and climbers to herbs and succulents. The diversity, ecological and economic importance, and biogeographic range of Moraceae makes it an ideal candidate for development as a model system for studying evolution. Much of my research focuses on the systematics, taxonomy, and evolution of the mulberry family, with a particular focus on the breadfruit genus (Artocarpus, about 75 species, mainly in Southeast Asia), the tribe Moreae (mulberries and allies, about 60 species, found in temperate and tropical regions worldwide), and figs (Ficus, perhaps 850 species).

Ethnobotany and the intersection between science and indigenous knowledge

Western and indigenous classification systems do not always agree, and integrating the two can both improve our knowledge of biodiversity and promote the conservation of indigenous classification nomenclature during a time of rapid social change.