Dianella G. Howarth

Dianella G. Howarth serves as Professor of Biological Sciences within the College of Liberal Arts and Sciences at St. John's University, where she leads research at the intersection of evolutionary biology and developmental genetics. Her work fundamentally explores how genetic mechanisms drive morphological evolution in plants, with particular emphasis on floral symmetry transitions and island adaptive radiations.

Her academic foundation includes a B.A. in Biology from the University of Pennsylvania (1997), Ph.D. in Biology from Harvard University (2002), and postdoctoral training at Yale University (2002-2007).

Dr. Howarth's research program integrates phylogenetic analysis, molecular evolution, and developmental genetics to investigate evolutionary mechanisms in plant development. She specializes in floral symmetry evolution, examining how duplications in the CYCLOIDEA gene family correlate with major shifts from radial to bilateral symmetry in eudicots, particularly within Dipsacales. Her laboratory also pioneers studies of Hawaiian adaptive radiations using Scaevola as a model system, analyzing genetic pathways like ROSEA (flower color) and LEAFY (inflorescence architecture) to understand rapid speciation. Current methodologies include virus-induced gene silencing (VIGS) for functional gene analysis.

Publication analysis from 1997-2008 reveals consistent focus on plant evolutionary genetics, with recurring themes of gene family evolution in floral symmetry, phylogenetic studies of Pacific island flora (especially Goodeniaceae and Rosaceae), and molecular mechanisms underlying adaptive radiations. Her work bridges molecular genetics with macroevolutionary patterns across diverse plant lineages.

Scientific Recognition:

• No specific awards or fellowships documented in source materials

Dr. Howarth actively mentors graduate researchers including Geraldine Boyden (utilizing VIGS to knockdown floral symmetry genes in Fedia) and Sreedevi Goparaju (phylogenetic analysis of floral symmetry gene families across angiosperms). Her laboratory maintains an open invitation for undergraduate researchers, fostering hands-on training in molecular evolutionary techniques. While specific grant details aren't provided, her research program demonstrates sustained activity through conference presentations at major venues including Botany and Evolution Meetings.

Her research laboratory, housed in St. Albert Hall, employs integrated approaches combining phylogenetics, gene expression analysis, and functional genetics to investigate the developmental genetic basis of plant morphological evolution, with ongoing projects focused on TCP gene networks in floral development and genetic drivers of Hawaiian Scaevola diversification.