User talk:AshLin/Snake scales

First, an obvious mistake: the subcaudals are under the tail -- they start after the anal scale. The body scales next to the ventrals are simply referred to as the first row of dorsal scales (even though they're often a little different from the other dorsal scales).

However, the biggest problem with this article as I see it, is that although it's a good enough effort for a description of the scalation of Amphiesma stolata, it's not the way I would go about writing a general article on snake scalation. There's simply more to it than that -- I'm sure entire books have been written on the subject. If I were you, I'd start with a general description of the subject and a list of all the different scales (with synonyms. Example: infralabials = sublabials = lower labials) that you come across in literature. If you want your article to last, you'll start by setting up a framework like this.

Once you really get going, you'll hopefully find yourself with so many different pictures and illustrations of the different scales (this may be a good source), that you'll be creating separate articles for most of them, each with a number of illustrations of the same scale (or absence thereof) in different species -- even though they're all still linked to the central article that you started with. From my point of view -- as someone who often describes the scalation of different species -- these would be ideal pages to link to. --Jwinius 16:21, 5 August 2006 (UTC)

Jaap, thank you for your comments. I have now downloaded Boulenger and have purchased Marshall latest Fauna of British India version. I am also looking up online resources. Please see version 0.2 of this article. Since I am a electrical engineer and untrained in Biology I may frequently make mistakes. I will keep updating it till it is reasonably complete and worth deploying. Regards, AshLin 16:32, 9 August 2006 (UTC)

That's okay. I'm a computer consultant, and this is just a hobby for me as well. But if you take it seriously enough and remained disciplined, even professional herpetologists will take you seriously. Your article seems to have improved a little, but I still feel that you need to think big like you're planning for the future.

To give you a better idea of what you're really up against, here's a PDF that I ran into recently that you might be interested in. It with a section that shown how important scalation is for identifying snakes:

• Leviton AE, Wogan GOU, Koo MS, Zug GR, Lucas RS, Vindum JV. 2003. The Dangerously Venomous Snakes of Myanmar, Illustrated Checklist with Keys. Proc. Cal. Acad. Sci. 54 (24):407-462. PDF at Smithsonian National Museum of Natural History, Division of Amphibians and Reptiles.

And remember, like they say in the technical world Assumption is the mother of all f..k-ups -- that applies equally to writing articles like this. Never assume anything when writing an article: I used to, and of course I didn't cite my references either. As a result, I'll be re-writing my own articles for some time to come. That may make it harder to write each article, but when you're finished, few will doubt what you've written. It's either that, or your article will be edited mercilessly. --Jwinius 17:45, 9 August 2006 (UTC)

Version 0.3 will come with footnotes and all the info I can garner from these resources. I have added a third image (from a dead Buff-striped Keelback). Please confirm that gular scales and mental groove is correctly indicated. Regards, AshLin 18:28, 9 August 2006 (UTC)

Citing your references, I see. Very good! It's also helpful if you include links to the (PDF) documents involved that you found on the the Internet, so that readers not only know where you got your information, but can also easy check up on it themselves. The way this document is organized is improving too. I also like the lists of different scales; you'll be able to use these later to make links to separate articles for each scale.

You got the mental groove right, but I'm not sure about the gulars; what you're pointing at may be considered a pair of posterior chin shields. I'm hardly an expert on scalation, but it seems to me that with Amphiesma stolata here, it may be considered that the ventrals are in contact with the posterior chin shields. With other species, such as Elaphe obsoleta, these are separated by gular scales. With A. stolata, it is perhaps possible to say that the only gulars are those scales located between the posterior sublabials (=infralabials) on the outside, and the ventral scales and posterior chin shields on the inside. But, again, I'm not sure: some of those "posterior chin shields" may be considered gulars anyway. To be sure, you have to find diagnostic (scale) info specific for this species (and hope that the gulars are described). On the other hand, a easier solution may be to just use a different species as your example for gular scales. --Jwinius 01:57, 12 August 2006 (UTC)

As long as you're also describing certain morphological aspects, such as the mental groove, in your article (which is fine by me), you may may as well include canthus. Like other future articles on individual scales, it would be nice if this article were eventually to include pictures and/or illustrations of strongly developed and weakly developed examples of the cathus rostralis. --Jwinius 11:30, 12 August 2006 (UTC)

Version 0.5 & 0.6

Version 0.5 comes with material added from most common govt websites which I assume are public domain. More headings and rearranged too. Version 0.6 has added images of scales of all kinds.

Please tell me what family classification to use for snakes.

Regards, AshLin 09:24, 13 August 2006 (UTC)

Brille or spectacle[3] is the angle between the flat crown of the head and the side of the head between the eye and the snout.[12]

This is incorrect. The Brille or spectacle is the transparent scale over the eye; snakes see through it and it's the reason why they don't need eyelids. The canthus (canthus rostralis) is a ridge -- more distinct in some species than others -- that runs from the supraocular area to the snout. The scales along this ridge are sometimes referred to as canthal scales or canthals. If this ridge is clearly visible, we say that the canthus is prominent or distinct. To put it another way, it's when the plane of the side of the head, between the eye and the snout, is at a clear angle (for example 90^o) in relation to the top of the head. Many vipers, such as Trimeresurus and Agkistrodon, have a distinct canthus, but also Dendroaspis and Ahaetulla. Most colubrids have a more rounded snout, so that the canthus is not distinct.

Your quote also brings up a second point regarding the way sources are cited. Unless you have direct access to a source, for example because you are reading directly from a book, a PDF or a website, it is not accurate to state that you are quoting from that source. In this case, you clam to be quoting from Mallow et al. (2003). However, I believe what you actually did was to quote my quote of Mallow, and then passed it off as if you quoted him directly. Correct? If so, this is potentially inaccurate, because you are assuming that my quote was accurate, and you know what they say about assumption...

In this case, I would expect you to simply link "canthus" to the Canthus (snake) article, where readers will find my quote of Mallow et al. (2003). That way, If it turns out later on that my quote was inaccurate, then that's my problem and not yours, because everybody can see that I was responsible for that mistake.

However, you're not the first person to make this mistake: I'm a reformed "reference citing criminal" myself, and have yet to clean up one last example of this: Daboia. In this case, the vast majority of those 36 cited references are 2nd hand: I got them from Mallow et al. (2003)! Mallow and his colleagues cited them in their book because (I must assume) they had direct access to them. Good for them for citing their sources! But, it's wrong for me to pass those sources off as my own.

Once Daboia is cleaned up, it'll look like Vipera ammodytes. The disadvantage is, of course, that afterwards everyone will see how limited my list of references for this article really was (I used just a few books for Daboia, and one of them I used over and over), but the advantage will be that I'll have been completely honest about where I really got my information. This absolute honesty is one of the cornerstones of what they call science.

By the way, if you want to modify Canthus (snake), be my guest. However, just as long as you do not disturb the essence of my statement or alter my references. You can delete my statement, and/or you can add information of your own even if it contradicts mine (although in those cases a discussion may follow), but just as long as you don't alter the meaning of my original statement, because that would render it inaccurate. --Jwinius 13:03, 13 August 2006 (UTC)

It was an error in the <ref/> tag. Simplified my canthus error as suggested. AshLin 13:21, 13 August 2006 (UTC)

Well, it looks like that error just popped up again...

As far as the rest is concerned, it's looks to be coming along pretty well. In the section "Nomenclature of scales," it would probably be a good idea to add a separate section for "Tail scalation" or something along those lines, not only because the tail is not really considered to be part of the body section, but because the scalation is different. Here, you can say things about the subcaudals (whether they are single or paired), whether these are smooth or keeled (as in Bitis arietans somalica) and about the tip. The end of the tail may simply taper into a tip, it may form a spine (as in Acanthophis), end in a bony spur (as in Lachesis), a rattle (as in Crotalus), or a rudder as seen in many sea snakes. I'm sure there are other variations as well. --Jwinius 11:46, 14 August 2006 (UTC)