Developmental Evolution of Fertilization Biology In Ancient Angiosperm Lineages

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1Award Abstract and Statement of Broader Impacts of Planned ResearchAfter a long period of empirical and intellectual stagnation, many of the century-old paradigms about theinitial phases of the diversification of angiosperms are in the midst of being rewritten. It is now evidentthat the earliest phases of angiosperm evolution may have been characterized by a very high degree ofdevelopmental experimentation and structural lability. In contrast to concerted efforts to study theevolution of floral morphology, vegetative anatomy and ecophysiology among ancient angiospermlineages, little attention has been paid to reconstructing the early diversification of embryological featuresamong flowering plants. It is the explicit goal of the planned research to study the basic and highlyinterrelated processes of female gametophyte development, double fertilization, and endosperm formationfrom an evolutionary developmental perspective in a set of species specifically chosen to represent thebreadth of diversity among basal clades of flowering plants.The following four interrelated questions will be addressed: 1) Did the earliest flowering plants possess aprocess of double fertilization, and have some ancient angiosperm lineages lost this process? 2) What wasthe developmental pattern and mature structure of the ancestral angiosperm female gametophyte? 3) Arethere additional and previously undocumented developmental patterns and mature structures of femalegametophytes among basal angiosperm lineages? 4) How has ploidy and genetic constitution (e.g. thematernal to paternal genomic ratio) of early angiosperm endosperm evolved? Beyond establishinggeneral developmental principles that can explain the diversification of female gametophyte structure andendosperm genetic structure and ploidy, the planned research will make a significant contribution tounderstanding more general aspects of the tempo and mode of character evolution during the earliestphases of the evolutionary diversification of flowering plants.The proposed research will contribute significantly to the development of human resources in thesciences. Members of the Friedman lab (undergraduates, graduate students, postdoctorals, technicians)have the opportunity to grapple with some of the most basic and longstanding questions in evolutionarybiology, and to develop independent intellectual skills. All members of the lab are charged withsignificant scientific responsibility. One Ph.D. student, Eric Madrid, is a member of an underrepresentedgroup in the sciences (Hispanic). He will be directly supported by the proposed research grant. Eric iscommitted to outreach efforts to improve the level of participation of minorities in the sciences andalready has had a major impact in serving as a role model for other members of underrepresented groupsin the sciences.Currently, most of the members of the Friedman lab are women and aspire to careers in the life sciencesas educators and/or practicing scientists. One technician, Kirsten Ryerson, who will be supported by theproposed research grant, plans to enter a career in public school science education. She will beginworking towards a teaching certificate for the state of Colorado next fall. Her direct engagement inresearch in the Friedman lab should directly benefit her future biology students. Another technician whowill be supported by the planned research grant, Amanda Redford, is keen to pursue researchopportunities that will lead to graduate study. Finally, through the REU program, undergraduates will besupported to gain first hand research experience in the laboratory of the PI, William Friedman. Inessence, while the vast majority of funds associated with this proposal will go to support the solution ofbasic and longstanding scientific questions, these funds will play a critical role in supporting thedevelopment of members of the next generation of life scientists and educators.Finally, it is anticipated, that the basic findings derived from the planned research will, as has been thecase in the past, be covered in college level textbooks. Thus, the research should have an impact onundergraduate and graduate curriculum development throughout the U.S.