To rate this resource, click a star:
Learn about phylogenetic systematics, the study of the evolutionary relationships among organisms, and how the field is shaping biological research today.
UC Museum of Paleontology
Students can read this tutorial for a review of phylogenies and tree-thinking.
Correspondence to the Next Generation Science Standards is indicated in parentheses after each relevant concept. See our conceptual framework for details.
- Scientists can test ideas about events and processes long past, very distant, and not directly observable.
- Classification is based on evolutionary relationships.
- Scientists use multiple lines of evidence (including morphological, developmental, and molecular evidence) to infer the relatedness of taxa.
- Evolutionary trees (i.e., phylogenies or cladograms) portray hypotheses about evolutionary relationships.
- Evolutionary trees (i.e., phylogenies or cladograms) are built from multiple lines of evidence.
- The principle of parsimony suggests that the phylogenetic hypothesis most likely to be true is the one requiring the fewest evolutionary changes.
- Evolutionary trees can be used to make inferences and predictions.