Scientists make hypothesis about evolutionary relationshipstatus based on observations and gather evidence to test those hypothees. We refer to this field of making testable hypothesis of evolutionary relationships as phylogenetic systematics. There are many types of data used that can be collected to help predict evolutionary relationships, and build phylogenetic trees. Morphological characteristics, DNA/molecular, ecological information,behavioral characteristics and development can all be useful.The more information that can be colleted about the group or taxon (plural taxa) that we are interested in, the more likely we are able to build an accurate representation of how these organisms are related.
