Hello everybody,
I’m working with a group of fish called hamlets and I have a total
sample size of 226 individuals. I have used 14 landmarks, Procrustes
superimposition and various statistical techniques to compare 6 groups,
which these fish are divided into (based on sampling location and
morphotype). One useful indicator of morphological similarity between
groups is Procrustes distance.
One thing which I am interested in doing is obtaining a data set of the
morphological distances between individuals. However, as this equates
to 1000’s of separate comparisons, I have calculated that if I were to
start aligning each pair of individuals, and find the procrustes
distance between them, then I wouldn’t finish working until somewhere
near 2007. I doubt it would be worth the effort to be honest.
This leaves me with 3 alternatives as I see it:
1. I can use a spreadsheet and the co-ordinates of all the aligned
landmarks to obtain the distance between pairs of individuals.
This would be quite easy to do but, as the pairs are not aligned
with each other (but with the entire dataset), the distances are
not Procrustes distances.
2. I could alternatively just analyse a small subsample, with
individuals taken from each group.
3. Or I could just give the whole thing up as a bad idea. I’ve not
found an example of somebody else using this kind of data, maybe
there is a reason why it shouldn’t be done.
I am new to morphometrics and if anybody has any ideas on this I would
be very grateful for your help.
If you wish to reply to me personally then my email address is:
[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>.
Cheers,
Ben Holt, University of East Anglia
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