Cantekin,

You might find the book "Geometric morphometric for Biologists" by Zelditch et al. very useful. You can read some about it here: https://www.sciencedirect.com/science/book/9780127784601#book-description

You can certainly analyze the shape of the parotid glands with asymmetries. It may be useful to quantify what proportion of your samples possess this asymmetry even. Individual heterogeneity in both shape and symmetry of the glands would be interesting in my opinion. Depending on how you choose your landmarks, there are a wide variety of ways you can analyze morphometric data. My only experience with these type of work is in the old fashioned hand caliper measurements, which I've analyzed using Linear Discriminant Analysis. If you intend to use a more advanced approach, such as taking scaled photographs and placing landmarks digitally via one of many softwares designed for this task, then I believe you may have more options. If you would like more examples of classic herpetological literature where they have performed these measurements (even directly on parotid glands) I'd be happy to dig some up for you.

Best of luck - Andrew

Andrew

I thank u for advices. I will take them into consideration. Actually, we analysed them with classical methods by measuring with the help of digital calipper, comparing statistically and etc. But about shape, we didnt performed anything. We only characterized them according to an article in literature. So i thought that geometric morphometrics would be so useful to detect exact results. And with ur advices i saw that it is appliable. I m grateful

Best regards-Cantekin

Merhaba Centekin,

As was mentioned above, you can, in principal, apply morphometric approaches to quantify and analyze the parotid glands shapes. It also depends on how you would acquire the images (2d or 3d) of these glands in order to quantify the landmarks, outlines etc...

This is a good webpage http://life.bio.sunysb.edu/morph/ have a look.

If you know some coding in R, then you could check some packages like Morpho, geomorph.

best,

Alik

I have seen the site u mentioned. But it will be different that trying by R packages. Thanks for advices alik

Best regards - Cantekin

It may most certainly be applicable. But a little more info is needed to provide you with useful tips. For one, how are you going to aquire their shape? Geometric morphometrics allows for the use of both landmarks and (sliding) semi-landmarks, but also of curves, both open and closed. Much depends upon how you intend to visualize the paridoid glands, in order to standardize their appearance somewhat. Asymmetry is not a problem in and by itself and (as you probably know better than I do) often is a specific topic of research interest. Geometric morphometrics has techniques to study asymmetry as well (flipping the left landmarks, to pool them with right, for instance, if asymmetry is not of specific interest). But unless you are able to standardize their apprearance in some kind of imagery (or image them in full, NMR style), GM methods won't be of much help.

Hans

İ thank u for informing about these illustrative and critical points. İ will take them into consideration.

Best regards.

Will you be using 2D or 3D images of the paratoid glands?

the R package Stereomorph looks to have 3D capability.

I'm not sure that landmarks would be the way to go for shape. If you were going to consider their position on the body then landmarks might be useful but if you're just looking at differences in the shape of the 2D or 3D ellipsoids there might be other methods that are easier to automate.

Good luck!