How to interpret a phylogenetic tree? How to answer questions like what is the evolutionary history of an organism? I did some search but most of the articles basically just say the evolutionary history represented by the tree. It's true but my question is about how to describe a phylogenetic tree in a language that looks professional and academic. You can't just tell me the information is embedded in the tree and just look at it.
You can't just tell me the information is embedded in the tree and just look at it.
Phylogenetic trees represent evolutionary distances between tree members as deduced from residue substitution patterns. In case it is not obvious, a distance between any two tree members is the shortest path obtained by tracing from one branch to another. From trees we can surmise not only how related tree members are on a relative scale, but also the order of events that shaped their evolutionary history. This is rarely perfect because events other than mutations and indels contribute to evolution, for example horizontal gene transfer.
It is worth mentioning that a phylogenetic tree represents a hypothesis (a reconstruction, if you will) based on available data. There are statistical measures, both at the level of individual branches and globally, of how likely this hypothesis is to be accurate. Adding or subtracting members can and does lead to different trees.