straight back pronounced withers divided back (two parts)

After generatining the picture of the connection of the optical backline and 
its bones creating those appearences by means of the page "The spinal column"
we can ask the standard what he prefers to see in Afghan Hounds:
 

The breed standards regarding backlines: All four Afghan Hound illustrations (see under "The spinal column") agree in one point: the back has to be straight from the shoulders to the hip bones. The FCI-Standard demands for a level back, a straight loin and a slightly falling croup. The America standard demands for a "back line appearing practically level from the shoulders to the loin", a slightly arched loin and a falling croup.   FCI-Standard and Australian standard AKC-Standard (U.S.) Back level, moderate length, well muscled,  back falling slightly away to stern.  Loin straight, broad and rather short.  Hip bones rather prominent and wide apart.  The back line appearing practically level from the shoulders to the loin.  Strong and powerful loin and slightly arched, falling away toward the stern, with the hipbones very pronounced.

How to interpret this clear demands for a "level back"? In colloquial speech the "back" unites the thoracic vertebrae and the lumbar vertebrae,  therefore the "back" reaches from the set on of neck till the hipbones. Does the American standard mean this: the points of the shoulder blades lie close the 2. thoracic vertebrae. Straight back from this point to the hip bones?? No, because the "practically" level reduces this demand. This interpretation doesn't play a role in the reality of the breed Afghan Hound. Anatomically the "back" is the thoracic spine, the thoracic vertebrae 1 to 13, therefore the back is the whole distance of the withers (1. to 8. thoracic vertebra) till a little behind the dip. I think no standard means that the line of the withers should be a straight line and horizontal to the ground. The old formers who have set up the breed standards didn't refer to this terminology. In the past the kynologists have divided the "back line" into two parts: the withers and the rest of the back. The withers are raised because of the long thorns of the first seven or eight thoracic vertebrae.  After them the remaining vertebrae have shorter thorns and are often called the "back".  Therefore the "back" starts with the eighth or ninth thoracic vertebrae and ends at the hip bones. In this interpretation the Dip (eleventh thoracic vertebra) is a point within a level back line.  This is meant by the formers of the FCI-Standard and is valid for the Australians as well. The FCI standards demands for a straight back from the end of the high withers to the croup: that means no or very little visible dip and no disturbation of the straight line due to pronounced vertebrae. The demanded well musculation across the whole back should not allow too much of visisble spine as well. The demand for a broad loin supports the impression of much musculation covering the whole spine. The FCI standard doesn't say anything about the withers, so it's not forbidden to have them high naturally. In my opinion the FCI standard most desires back line no.1. (see below) I know that some Americans want to interpret their standard in this way, too. But does the wording "level from shoulders to the loin" allow this?  Historically this special American wording has taken the place of the above British discription. Why have the formers of the AKC standard changed the wording in this way? Wasn't they satisfied by the back line demanded by all the older British standards? Did they feel that another discription describes their dogs having in mind more exactly? I don't know, but I think the wording does allows a little different interpretation:  "practically level" is almost level and perhaps allows a slightly falling down of the withers to a visible dip   and a slightly up across the vertebrae behind the dip. Additionally it's supported a slight arch of the loin  up and down towards the croup, which could lead astray to visible lumbar vertebrae to show the demanded arch on first sight. But is such a backline the same as the most desired by the FCI standard, back line no.1? The pictures tell something else... Aditionally this standards says nothing about the musculation of the back, only loins have to be strong and powerful, which can be achieved by the musculation on the sides. The vertebrae itselves haven't to be covered by musculation. The less musculation (in comparision to the FCI standard) shows up in two points: no muscular back and no broad loin. Last but not least the "very" pronounced hip bones exclude too much musculation, which would cover this stressed feature. Surprise: Does this show how much influence does every word in the standards play? Or is it the different foundation gene pool? .

Optical appearances of back lines in photographs, 
devided into condition of musculation & food (no. 1-3) and the flexibility of tendons and ligaments (no. 4)

(I've not translated my opinion why there are those different toplines,
but I will tell You my system how I've categorized them:

Back line no. 1 has "short withers" and long back without visible dip.
Back line no. 2 shows "long withers" till the dip, which is clearly determinable due to the following visible vertebrae.
Back line no. 3 allows to count each vertebrae due to distinct visibility.
Back line no. 4 unites all previous back lines and adds the new aspect of flexibility at the dip, 
                        with allows different degrees of the slope of the wither segment.

The reasons are not transalted into Englisch, only in German (on the German page).
Maybe added in future.

Large collection of photo examples: 
Please choose for further examples the desired picture out of the following table:
 

Back line no. 1: (FCI)	Back line no. 2: (AKC)	Back line no. 3: (visible vertebrae)
"short withers" and long level back  without visible dip or arch of loin	"long withers" till the dip, which is clearly determinable due to the visible vertebrae	allows to count each vertebrae  due to distinct visibility
Back line no. 4: (Flexibility)
unites all previous back lines and adds the new aspect of flexibility at the dip for different degrees of the slope of the wither segment

If You would like to have further back lines presented on this website, please contact me and send the picture!
As well let me know Your comments.