Just in case someone would like to comment on the tree...
The node that unites
Scotocerca to acrocephalids has a ML bootstrap support below 50%, and a Bayesian posterior probability of .70. Nodes with this type of support generally mean close to nothing, I'm afraid. (As a rule, bootstrap support should in any case be above 70%, and Bayesian PP above .95.)
(Additionally, I'd be a little bit cautious about the sequence itself as well. This is the only available sequence of
Scotocerca to date, and it was not produced by Barhoum & Burns themselves - they got it from GenBank [
http://www.ncbi.nlm.nih.gov/nuccore/7381261], where it is the only sequence associated to a paper that, as far as I can judge, never appeared in press. This means that we don't really know how the sequence was obtained, and have no way to assess its quality. GenBank is filled with sequences that have a similar status and, in my experience, these are quite prone to include incorrect data... I'm not saying it's the case for this one, of course - but, still, I'd keep this in mind when assessing the case.)
I've tried to play a bit with the sequence. It clearly is not very close to any (other) published cisticolid cyt-b sequence (including those of
Prinia), but it is also pretty distant from all other sylvioid groups. It tends to move around depending on which other taxa I include in the tree - often popping out as distantly basal to the acrocephalids, as in Barhoum & Burn's tree, but I also get it distantly basal to other groups, including in some cases cisticolids, with some combinations of taxa. (I've attached such a tree - I didn't try to assess supports on this one, because the data set is quite large and it would take ages to do on my PC.)
This sequence clearly does not
add support to
Scotocerca being a cisticolid, but I do not believe either that it can be used to say that it isn't one (at least unless you want to use the data as evidence that it forms a monotypic family). That said, if the sequence is correct, for
Scotocerca to be a cisticolid, it would have to be a very basal (divergent) one. In any case, not at all particularly close to any of the
Prinia spp. that have been sequenced up to now.
L -
PS - Richard: Yes, there is ample evidence that
Prinia is a cisticolid. E.g.:
http://dx.doi.org/10.1016/j.ympev.2005.05.015, and
http://dx.doi.org/10.1016/j.ympev.2006.07.008. (The first one is available from Per Ericson's website, but you have to
ask for a username and password to get access.)
