I assume you mean that you are interested in the number of substitutions/ changes along a branch per unit of time?

To convert from phylogenetic branch length to time, you need some calibration point (node), or preferably several, in your tree which represents a "known" (or at least informed) date or range of possible dates encompassing a divergence event. This could come in the form of fossil evidence, geological evidence, etc. The basic logic here is that with a known node, you can calculate the rate of mutations along a branch and apply that rate to all branches in the tree.

I would recommend that you look into divergence dating using Beast as there are many nice tutorials available. Keep in mind that some things have changed with version updates, and so be aware which version a tutorial is referring to (I have found some issues with this, in the formatting of XML required by different versions).

http://beast2.org/

I assume you mean that you are interested in the number of substitutions/ changes along a branch per unit of time?

To convert from phylogenetic branch length to time, you need some calibration point (node), or preferably several, in your tree which represents a "known" (or at least informed) date or range of possible dates encompassing a divergence event. This could come in the form of fossil evidence, geological evidence, etc. The basic logic here is that with a known node, you can calculate the rate of mutations along a branch and apply that rate to all branches in the tree.

I would recommend that you look into divergence dating using Beast as there are many nice tutorials available. Keep in mind that some things have changed with version updates, and so be aware which version a tutorial is referring to (I have found some issues with this, in the formatting of XML required by different versions).

http://beast2.org/

Thank you Tyler Chafin

Hey Rahul,

You might want to explore PAML too -- http://abacus.gene.ucl.ac.uk/software/paml.html. It is frequently used in the evol biol community to test for differences in rates of mol evol along branches, and at sites along branches of a phylogenetic tree. Differences can arise from things like positive selection, or other forces that violate neutrality. It is good to have a hypothesis going in though, rather than testing branches willy nilly.

Adam

Hi Dear

Beast software is the best way to predict parsimony informative sites. If you r unable to run the software then try MEGA software.

I will try these softwares now,

Thank you Partha Sarathi Mohanty & Adam James Bewick

Hi, Dear

Aligns the sequences and recognizes the number mutations between the different sequences (softwar sequacing analyser) and you have an estimate of evolutionary time between different taxon on the basis of the molecular clock