A Process-Based Approach to the Study of Flower Morphological Variation

Abstract

One of the most striking elements of angiosperm evolution is the diversity of floral forms represented. Beyond modifications of existing structures, flowers can evolve novel elements that are often linked with functions associated with effective or efficient pollination. Yet despite this diversity of floral forms, certain flower structures are highly conserved, as are many of the genes that underlie their basic form. Here, a process-based approach is discussed as a means of investigating floral morphological diversity and studying the evolution of floral form. First, the advances in understanding the evolution of floral form derived from the traditional morphogenetic approach are discussed. Then, a discussion follows on the unique ways that a process-based approach can contribute to our understanding of developmental evolution leading to organ elaboration and morphological diversification, focusing on polarity as a case study. Finally, the current limitations of a process-based approach are discussed, while pointing out future venues of research in this area that might greatly improve our understanding of morphological diversification of flowers.