Evolutionary biologists use morphological, anatomical, ecological, genetic, and other forms of data in phylogenetic analyses to test hypotheses that investigate different biological questions. Because each type of data has its own, assumptions, strengths, and limitations, it is important to recognize these features of the data and take them into consideration when interpreting results.
This laboratory module explores plant diversity and evolution through phylogenetic analyses using 1) plant morphological and anatomical data and 2) molecular data. The combination of analyses using different forms of data will promote deeper understanding of important evolutionary innovations, patterns of diversity, and major trends in plant evolution. In this exercise, you will collect morphological data to construct an initial phylogeny of the study organisms that describes broad patterns of trait evolution among taxa. Next, you will compare your data with four molecular phylogenies for a more fine-grained analysis of relationships among taxa. You will then use the data from the different data sets to develop a consensus phylogeny to describe relationships among taxa and patterns of trait evolution. Comparisons of phylogenies also provides an opportunity for critical analysis of phylogenetic data interpretation.