One could do that computationally but I would worry about the homology it might
imply for such variable leaf shapes. You might try it and then check to see if,
for example, a lobe on one leaf might be 20% of the linear distance around the
outline but in another it might be 30% of the way around. In such a case the
lobe on one leaf would effectively be treated as homologous to a location
between lobes on another leaf. If so, does that make biological sense for your
study? If simple leaves were also included the implied homology of a point
along its outline to that of one of the lobed leaves might be pretty arbitrary.
Would be better if one knew something about the development of these leaves
(which I do not!) and used that knowledge.
An alternative would be to use outline methods to group shapes for the purpose
of say identification with little implication that groups need be biologically
meaningful. Sorry to be rather negative but I find highly variable leaf shapes
difficult to put in a simple standard framework. Perhaps others will have
F. James Rohlf, Distinguished Professor, Emeritus. Ecology & Evolution
Research Professor, Anthropology
Stony Brook University
From: Tina Klenovšek <tina.klenov...@um.si>
Sent: Wednesday, March 14, 2018 12:28 AM
To: f.james.rohlf <f.james.ro...@stonybrook.edu>
Subject: RE: [MORPHMET] digitizing very variable leaves
Thanks to everyone who answered.
Dear Dr. Rohlf,
I assumed great variability would be a problem.
I was thinking the best way of digitizing would be to draw a curve on the
outline of each leaf (simple and lobed leaves). Resample curves by length with
approx. 40 landmarks. Then append curves to landmarks. Two landmarks, the leaf
tip and base, would be fixed others could be defined as semi-landmarks. Is this
Alternatively, we could analyse simple and lobed leaves separately.
Thank you a lot for your help.
From: f.james.rohlf [mailto:f.james.ro...@stonybrook.edu]
Sent: Wednesday, March 14, 2018 3:59 AM
To: Tina Klenovšek
Subject: Re: [MORPHMET] digitizing very variable leaves
An assumption of the usual GMM methods is that shape variation is "small". I
think these leaves exceed this quite a bit! Another problem is landmarks. How
to match leaves with and without lobes?
F. James Rohlf, Distinguished Prof. Emeritus
Dept. Anthropology and Ecology & Evolution
-------- Original message --------
From: 'Tina Klenovšek' via MORPHMET <email@example.com
Date: 3/12/18 10:56 AM (GMT-10:00)
To: firstname.lastname@example.org <mailto:email@example.com>
Subject: [MORPHMET] digitizing very variable leaves
we would like to digitize tree leaves that are very variable (from simple oval
to strongly lobed on one tree).
1.) I am wondering if TpsDig can do some kind of automatic digitizing like
the LeafAnalyser software:
http://www.plant-image-analysis.org/software/leaf-gp, which evenly distributes
a defined number of landmarks on the leaf outline...
LeafAnalyser does not seem flexible or precise enough. Or I can’t use it
properly. Any experience?
2.) Is it possible/sensible to put objects that are so differently shaped
(photos attached) into the same group or is it better to analyse simple and
lobed leaves separately?
I apologize if similar questions have been already answered...
doc. dr. Tina Klenovšek, koordinatorica doktorskega
študijskega programa Ekološke znanosti
Univerza v Mariboru | University of Maribor
Fakulteta za naravoslovje in matematiko
Faculty of Natural Sciences and Mathematics
Koroška cesta 160, 2000 Maribor, Slovenija
T: +386 41 808 366
E: <mailto:ime.prii...@um.si> tina.klenov...@um.si,
MORPHMET may be accessed via its webpage at http://www.morphometrics.org
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