Honors Program Thesis (UNI Access Only)

First Advisor

Julie Kang


Ampelopsis--Classification; Leaves--Development;


The primary aims of this study were to use quantitative analysis to classify species based on leaf form and use these quantified leaf forms to investigate evolutionary mechanisms that cause change in leaf shape morphology within Vitaceae. Ampelographic techniques to effectively distinguish leaf forms and investigate the life history within Ampelopsis over the last forty million years were successfully developed and executed. Mean shapes and principal components of leaf shape variability along with its proportional responsibility for total variation were obtained on interspecies and intraspecies levels using the SHAPE program. Variability of certain morphological traits proved useful for identifying key differentiating parameters as well as the dynamicity of phenotypes in closely related species. Quantitative vein analysis and general shape indicators were studied. Parameters that effectively distinguish all sampled leaf forms within Ampelopsis were identified. These parameters include perimeter to area ratio, circularity, sinus 1 length, sinus 2 length, and the secondary vein 1/secondary vein 2 ratio.

Previous phylogenetic research on Ampelopsis was supplemented with this morphometric analysis of leaf shape to understand evolutionary mechanisms that drive leaf shape morphology changes within Vitaceae. Evolutionary mechanisms identified and investigated include geographic dispersals, time of divergence, climate changes, stability of various leaf forms, and angiosperm ancestry patterns (see conclusion for specific implications of these mechanisms).

Additionally, results obtained in this study confirmed there is indeed a morphological separation between North I and North II clades. This study supports the claim that the Asia lineage in North I evolved from dissected leaf ancestral species and plausible phylogenetic relationships were proposed for A. vitifolia.

Date of Award



Department of Biology

University Honors Designation

A thesis submitted in partial fulfillment of the requirements for the designation University Honors

Date Original


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