What is a phylogenetic tree?
A phylogenetic tree, also known as a phylogeny or evolutionary tree, is a powerful tool that visually depicts the evolutionary relationships between organisms. It's like a family tree for all living things, but instead of parents and children, it shows how species have descended from a common ancestor over time.
What are the main features of a phylogenetic tree?
- Branching Pattern: The branching pattern of the tree reflects the evolutionary history of the represented organisms. The further two species diverge on the tree, the longer ago their common ancestor lived.
- Nodes and Branches: Branching points (nodes) represent the divergence of ancestral lineages into new species. The lengths of branches can sometimes indicate the amount of evolutionary change that has occurred. (Note: Branch lengths don't always signify time in some trees).
- Rooted vs. Unrooted: Rooted trees have a designated root representing the most recent common ancestor of all organisms in