Judith X Becerra

Judith X Becerra

Associate Research Scientist, Biosphere 2
Associate Research Professor
Associate Professor, Entomology / Insect Science - GIDP
Associate Research Scientist, BIO5 Institute
Member of the General Faculty
Member of the Graduate Faculty
Primary Department
Department Affiliations
Contact
(520) 621-9397

Research Interest

Judith Becerra, PhD, is an evolutionary ecologist interested in insect-plant interactions. Her current research combines ecological, biogeographycal, and chemical information with molecular phylogenetics to identify macroevolutionary patterns of host shifts, co-adaptive forces shaping coevolution and evolutionary strategies of plant chemical defenses. She is also interested in plant and insect diversification and ecological chemical interactions between insects and plants. Extensive research has been pursued in the Mexican tropical dry forests with the plant genus Bursera and their herbivores, the beetle genus Blepharida. These two groups have interacted for the last 100 million years and are both highly diverse, with spectacular adaptations and counteradaptations.

Publications

Becerra, J. X. (2012). The impact of herbivore-plant coevolution on plant community structure. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 104(18), 7483-7488.
Becerra, J., Venable, D., Evans, P., & Bowers, W. (1991). Interactions between chemical and mechanical defenses in the plant genus Bursera and their implications for herbivores. AMERICAN ZOOLOGIST, 41(4), 865-876.
Becerra, J. X. (2015). On the factors that promote the diversity of herbivorous insects and plants in tropical forests. Proceedings of the National Academy of Sciences of the United States of America.

Some of the most fascinating and challenging questions in ecology are why biodiversity is highest in tropical forests and whether the factors involved are unique to these habitats. I did a worldwide test of the hypotheses that plant community divergence in antiherbivore traits results in higher insect herbivore diversity, and that predominant attack by specialized herbivores promotes plant richness. I found strong correlative support for both ideas. Butterfly diversity was greatest in regions where the community average species-pairwise dissimilarity in antiherbivore traits among plant species was highest. There was also a strong positive relationship between specialized (insect) vs. generalized (mammal) herbivores and plant richness. Regions where herbivory impact by mammals was higher than that of insects tended to have lower plant diversities. In contrast, regions in which insects are the main consumers, particularly in the Central and South American tropics, had the highest plant richness. Latitude did not explain any residual variance in insect or plant richness. The strong connections found between insect specialization, plant defense divergence, and plant and insect diversities suggest that increasing our understanding of the ecology of biological communities can aid in considerations of how to preserve biodiversity in the future.

BECERRA, J., & LLOYD, D. (2001). COMPETITION-DEPENDENT ABSCISSION OF SELF-POLLINATED FLOWERS OF PHORMIUM-TENAX (AGAVACEAE) - A 2ND ACTION OF SELF-INCOMPATIBILITY AT THE WHOLE FLOWER LEVEL. EVOLUTION, 46(2), 458-469.
Venable, D. L., Flores-Martinez, A., Muller-Landau, H. C., Barron-Gafford, G., & Becerra, J. X. (2000). Seed dispersal of desert annuals. ECOLOGY, 89(8), 2218-2227.