If one is constructing a phylogeny of reptiles using DNA sequence data, which taxon (birds, mammals, amphibians, or fish) might be suitable to use as an outgroup?

Key Concepts

Phylogeny

Phylogeny refers to the evolutionary history and relationships among species or groups of organisms. It is often represented as a tree-like diagram, illustrating how different taxa are related through common ancestors. Understanding phylogenetic relationships is crucial for classifying organisms and studying their evolutionary processes.

Outgroup

An outgroup is a taxon that is closely related to the group being studied (the ingroup) but is not part of it. In phylogenetic analysis, outgroups are used to provide a reference point for determining the evolutionary relationships within the ingroup. Choosing an appropriate outgroup helps clarify the characteristics that are derived or ancestral in the ingroup.

DNA Sequence Data

DNA sequence data involves analyzing the nucleotide sequences of organisms' genomes to infer evolutionary relationships. This molecular approach provides a more precise understanding of genetic similarities and differences among taxa. In constructing phylogenies, DNA data can reveal evolutionary patterns that may not be evident from morphological characteristics alone.