Plant Evolutionary Morphology
When you examine morphological variation across major groups of life, it is clear that plants exhibit a disproportionally greater number of forms. The remarkable amount of variation represents millions of years of adaptation to environmental variation, function, and pollination. Our lab is interested in understanding the evolutionary processes that have generated such a remarkable amount of morphological forms in plants. We apply a macroevolutionary approach that takes advantage of traditional anatomy and morphology methods, phylogenetic comparative methods, ecology, and genomics to better understand how forms have evolved through time. Below, we outline a subset of our research that typifies our approach to study plant evolutionary morphology.
STaminode evolution |
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Staminodes are infertile stamen that either evolve a secondary function or are rudimentary structures. We have been fascinated by the evolution of these structures, especially when they represent functional cooption. We have been studying staminode evolution across angiosperms to determine how they arise and develop in various groups, and have been interested in investigating common evolutionary transitions in staminodes across clades.
SeeD evolution
The morphological/anatomical innovation of seed evolution makes a remarkable system to study the evolution of forms because they are relatively simple structures that are under strong selection. We have been studying large-scale patterns of morphological evolution across plant families under a phylogenetic comparative framework. We have also been interested in answering how morphological changes occur concomitantly with changes in dispersal ecology at the macroevolutionary scale and how morphology evolves to meet the functional demands of dispersal.
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Evolution of dispersal function
Among all of the stages in a plant's lifecycle, the dispersal of seeds/fruits is perhaps the most important, yet vulnerable stage. Because of the importance of dispersal to continue the lifecycle, there is strong selection on seeds and/or fruits to maximize dispersal success. We are interested in understanding how selection optimizes dispersal function, especially as it pertains to soil specialization, as well as other morphological traits.
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Morphological evolution in podostemaceae
Podostemaceae is the most species-rich, all-aquatic plant-family. The family is hypothesized to have evolved into water from a terrestrial ancestor, which has led to a remarkable amount of morphological evolution. The family has three centers of diversity: South America, southern Asia, and equatorial western-Africa. Our work in the African Podostemaceae has included taxonomic and systematic work, and is now largely centered on understanding the remarkable morphological adaptations of this group associated with transitioning to aquatic ecosystems.
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Adaptive radiations
Why some groups have much more species diversity than other closely related groups is a long and nuanced question in evolutionary biology. We have been interested in understanding triggers of ecological opportunity and adaptive radiation. We have applied statistical phylogenetic approaches to understand the dynamics of these remarkable diversification events. In addition to outlining some theoretical work on adaptive radiations, we have been primarily interested in understanding how movement to new continental areas has spurred, or in many cases, not spurred ecological opportunity and adaptive radiations.
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