Great FREE graphics program to help identify difficult salamanders

[FrogEyes]

From: Print Clock - A method for dating early books and prints a website from a herpetological lab [Dr. S. Blair Hedges] which found a need to identify the date of publication of undated antique books:

I used ImageJ (ImageJ) for the study and recommend it. It is free and maintained by the U.S. National Institutes of Health (NIH). Just visit the site and go to "downloads." Versions are available for almost any operating system. Other image analysis packages are available, and probably could be used as well. Although images can be thresholded and measured for gray level in Photoshop, that software is not designed for image analyses.

Among the many features of this public domain software, I will focus only on the one group of HUGE relevance here (from “features”):

Analysis:
Measure area, mean, standard deviation, min and max of selection or entire image. Measure lengths and angles. Use real world measurement units such as millimeters. Calibrate using density standards. Generate histograms and profile plots.

Presumably all of these tools and features are of great use to the NIH, because they help the analysis of tissue images [of note - the late head of NIDDK at NIH was Dr. John Daly, who collaborated in the study and descriptions of many poison frogs, including Phyllobates terribilis]. The image analysis can show organ or tumor size, composition based on color, etc. For US...the benefits are similar...

I commented some time ago about the difficulties identifying Pachytriton species. Many incorrect assumptions have been made about identifying the species based on color and pattern. While there are colors and patterns typical of one species or another, there is often so much overlap as to be highly unreliable. However, each species does have reliable morphometric characters - lengths and widths of body parts and their relative proportions. We discussed the fact that one could photograph animals with something measurable in the picture [such as a ruler], and then analyze the pictures in Photoshop or PSP. It's doable, but laborious. So now we have access to free imaging software that provides those measurement tools! Collect the data, plug it into a spreadsheet [I have one which includes known data for all Pachytriton], and then compare! This should help with other morphometrically defined species, such as H.fudingensis, H.orientalis, and the confusing animals which look like H.fudingensis, but SEEM to have H.orientalis proportions. “Seem” meaning that I can't be sure how accurate my photo measurements were, made as they were without measuring tools.

[Rodrigo]

It´s a long shot, but any chance morphometrics could be used with any reliability for the "cyanurus" group?

Regardless of that, thank you for posting this!

[FrogEyes]

Probably, but the trouble is that such data likely doesn't exist to be compared.

[Rodrigo]

Well, hopefully it´ll exist some day and then i´ll give it a go. Thanks for your quick answer.

[FrogEyes]

There is also a derivative program called "Fiji", which incorporates many of the plug-ins, including a plug-in/macro menu, with support of ImageJ2. I somehow managed to miss installing ImageJ, and have just installed Fiji instead.

Fiji Is Just ImageJ