Building trees of algae: some advances in phylogenetic and evolutionary analysis

Molecular phylogenetics has become a prominent aspect of algal systematics. The field of phylogenetic reconstruction is fast-evolving and novel techniques take time to penetrate taxonomic research. We highlight a selection of advances in phylogenetic inference and evolutionary analysis methods that could, in our opinion, benefit algal systematic studies. The focus of the paper is on model-based techniques. Following a brief introduction to maximum likelihood and Bayesian phylogenetic inference methods, we address model selection and partitioning strategies, and illustrate some issues concerning systematic error (phylogenetic bias), data saturation and tree rooting. We discuss the importance of experimental design (taxon and character sampling) and explore methods to test the reliability of phylogenetic results. Finally, we address methods for estimating ancestral states of discrete and continuous characters and techniques for dating phylogenetic trees. For each of these topics, we provide a brief circumscription, refer to the more specialized literature, and list a selection of software to carry out the analyses.