Molecular-Clock Dating Using MrBayes - Seminar and Workshop
22 April - Stockholm: 09:30-11:30, Rum 540, Institutionen för ekologi, miljö och botanik (Lilla Frescati), Stockholms universitet
23 April - Uppsala: 13:15-15:15, Lärosal 4, Evolutionsbiologiskt Centrum, Uppsala universitet
Chi Zhang*, Swedish Museum of Natural History, Stockholm
Johan Nylander, BILS/Swedish Museum of Natural History, Stockholm
MrBayes - the most often used software for Bayesian phylogenetic analysis - has
included many new features since version 3.2. In this seminar, we will
highlight some newly implemented functionality, with focus on the
molecular-clock dating capacities of the current version (v.3.2.4).
The seminar will consist of two parts, where following a presentation* giving
the necessary backrground information, there will be a hands-on tutorial where
participants are encouraged to bring their own data (and computers).
There are two approaches on dating using molecular data: node dating and
total-evidence dating. Node dating calibrates the internal nodes of the tree by
assigning distributions using information from external sources, such as the
fossil record. Total-evidence dating uses the morphological data from fossil
record and morphological and sequence data from recent organisms together to
infer the dates. Several steps involve in Bayesian dating analysis, including
data partitioning, node or fossil age calibration, and setting priors for the
tree and the molecular clock model. I will describe the available calibration
probability distributions, clock tree priors - especially the fossilized
birth-death prior for total-evidence dating, and relaxed clock models, through
a step-by-step tutorial of MrBayes.
The program (MrBayes v.3.2.5) is available from
Participants in the practical part are encouraged to bring their own computers
with the software installed from the above mentioned URL's.