-------- Original Message --------
Subject: Re: Visualization of non-allometric shape change in MorphoJ
Date: Fri, 20 Jan 2012 03:27:17 -0500
From: andrea cardini <[email protected]>
To: [email protected]

Dear Marko,
Viscosi and I
(http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0025630)
 tried to provide a simple (and sometimes simplistic) step by step
guideline to this and some other analyses in taxonomic studies using GMM.
We also describe how to first use TPSRegr (for 2D data) to test slopes, as
described by Rohlf in the help file, before trying any 'size-correction'.
In the paper you'll find refs pointing to more sophisticated and
potentially more accurate approaches.

I would try to replicate the analysis following that guideline. If you
still have problems, let me know. I'll do my best to find a spare moment to
see if I can help (after the next week!).

The V&C paper is on tree leaves but most of what we describe is pretty
general. I can send you a pdf of that paper with a comment on how to modify
one of the analyses for studies on animals. However, this does not concern
the 'size-correction', which is the same regardless of whether it's leaves,
bones or other structures.

Good luck.
Cheers

Andrea

At 14:21 19/01/2012 -0500, you wrote:


-------- Original Message --------
Subject:        Visualization of non-allometric shape change in MorphoJ
Date:   Tue, 17 Jan 2012 08:24:36 -0500
From:   Marko Djurakic <[email protected]>
To:     Morphmet <[email protected]>



Dear morphometricians,

I’d like to compare sexual shape dimorphism and its patterns among four
groups after size correction. I have some struggle regarding
visualization of non-allometric shape changes in MorphoJ.

Here is step-by-step procedure that I used in analysis:
My dataset contain four groups (A, B, C and D) and within each of them
there were two sexes (male and female) as subgroups.

1. I did the GPA on the whole dataset.
2. First I was interested in SShD within each group and therefore I
subdivided dataset by “group” factor in preliminaries menu, unchecking
the “separate procrustes fit”, resulting in four new datasets (A, B, C
and D). Each of them contains 2 classifiers (sex and group). Please
consider that group classifier was invariant then.
3. I performed regression analysis pooled by sex in each group
(regression slopes between sexes were homogeneous) – overall four
separate regressions. To visualize shape changes of allometric and
non-allometric component “averaged observation by” option was used in
preliminaries menu. As averaging factor I used “sex” and “group”,
respectively. I did the same averaging procedure *for* each group.

Averaging by sex results: MorphoJ showed predicted and residuals shape
changes for both females and males (4 graphs at all per group)

Averaging by group results: MorphoJ showed predicted and residuals shape
changes for a group (2 graphs per group), but they appeared precisely
the same regarding direction and magnitude of the shape change which was
unusual.

Main objective is to visualize allometric and nonallometric shape change
of each group.

Did I miss some step or it is just a bug in the program MJ? If so, how I
can visualize non-allometric shape change in MJ? I used 1.04a version of
MorphoJ. Additionally, I did the same analysis on other dataset and
results were the same.

--
MarkoĐurakić, PhD student,
University of Novi Sad
Faculty of Sciences
Department of Biology and Ecology
Dositej Obradović  Square 2
21 000 Novi Sad
Serbia

e-mail:[email protected]



Dr. Andrea Cardini
Researcher in Animal Biology
Dipartimento di Biologia, Universitá di Modena e Reggio Emilia, via Campi
213, 41100, Modena, Italy
tel: 0039 059 2055017 ; fax: 0039 059 2055548

Honorary Fellow
Functional Morphology and Evolution Unit, Hull York Medical School
University of Hull, Cottingham Road, Hull, HU6 7RX, UK
University of York, Heslington, York YO10 5DD, UK

Adjunct Associate Professor
Centre for Forensic Science , The University of Western Australia
35 Stirling Highway, Crawley WA 6009, Australia

E-mail address: [email protected], [email protected],
[email protected], [email protected]

Webpage: http://sites.google.com/site/hymsfme/drandreacardini
Datasets:
http://ads.ahds.ac.uk/catalogue/archive/cerco_lt_2007/overview.cfm#metadata
Editorial board for:
        Zoomorphology:
http://www.springer.com/life+sciences/animal+sciences/journal/435
        Journal of Zoological Systematics and Evolutionary Research:
http://www.wiley.com/bw/journal.asp?ref=0947-5745&site=1
        Hystrix, the Italian Journal of Mammalogy:
http://www.italian-journal-of-mammalogy.it/




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