Phylogenetic tree
A branching diagram showing evolutionary relationships. Each branching point is a common ancestor. Species closer together on the tree share a more recent ancestor.
Last updated
Analogy
A family tree for species.
In practice
Humans are more closely related to chimpanzees than to gorillas, as DNA comparisons show.
Practice
Flashcards
- What does a branch point in a phylogenetic tree represent?A common ancestor of the groups that branch from it.
Interview questions
- Describe the evidence that supports evolution from a common ancestor.
- Fossil record
- Homologous structures
- DNA and protein similarity
- Observed evolution
Questions people ask
How are phylogenetic trees built?
Scientists compare traits, most often DNA sequences, across species. Species with more similarity are placed closer together. Computer methods look for the tree that best explains the data. As more genomes are sequenced, trees are refined, and some old classifications based on appearance alone have been changed.
What are the three domains of life?
Bacteria, Archaea and Eukarya. Bacteria and Archaea are both prokaryotes but differ in their cell chemistry and genes. Eukarya includes all organisms with a nucleus: animals, plants, fungi and protists. Genetic data show that Archaea are more closely related to Eukarya than to Bacteria.