Hi all,
I was at this site: http://www.pnas.org/content/101/24/9003.figures-only
and I would be interested in knowing what are time frames
for the branches of the tree shown?
Any advice, URLs, references appreciated.
TIA
Paul…
Hi Paul and welcome,
well, I’m not an evolutionary biologist, but if it were a Sunday and there was nothing to do and it was raining etc… you could work out the time estimates. You need figure 2 though, not figure 1. Figure 2 gives the likelihood estimates for substitutions per site. from the figure you can get a rough idea of the number of substitutions per site between taxa and then use a generic substitution rate.
The calculation is essentially that divergence time = number of substitutions between two taxa/2 x substitution rate (K/2ν). However, assuming a constant v is problematic and things get complicated when you don’t assume this. Also, measuring the figure with any accuracy (I didn’t check whether the authors had included a supplementary table) is also problematic.
Perhaps the easiest option would be to contact the corresponding author and ask them the same question?
The following paper is also not bad as an overview/primer;
http://evol.bio.lmu.de/_teaching/evogen/Tut9+10.pdf
Regards
Steve