"Narrow Skull"   We have all heard it.  In the Illustrated Guide put out by the American Lhasa Apso Club we see a photo of an apso head with the caption "Broad backskull and high set ear" (set next to an altered photo which allegedly shows a "correct" narrow head).  If we take a look at other standard illustrations such as the Havanese, it calls for a "broad" backskull.  However when we put hands on these two dogs, the heads - at least the posterior cranial portions of the heads are identical.  Yet one is called "broad" and the other "narrow"!  What is wrong here?

Well first off, we lack a clear definition of several words:  "narrow", "skull", "head", and "backskull" are the principal questionmarks.

What is "narrow".  Well one definition is "length greater than width".  Obviously that is an absolute meaning as opposed to a relative meaning, i.e. "narrow as compared to...."  Unfortunately both are applied to the apso head.  Even the broadest apso head is absolutely "narrow", since I have yet to see one that is not longer than it is wide.  So what is meant by "narrow" in our standard? "Compared to what? Could it be that at the time the standard acquired those words, the breed was just in the process of being differentiated from the Shih-Tzu? (1933-35)  For the moment, let's accept an absolute meaning (so much less ambiguous).

Head.  The head is everything north of the neck.  It is made up of the bony skull, or Cranium, and the facial bones,  along with the soft tissues associated with the bony skull and facial bones. The skull is comprised of  pairs of bones: Frontal, Parietal, part of the Temporal, Occipital,  Sphenoid, and Ethemoid.  The facial bones (everything else) include the Nasal, Palatine, Maxillary, Zygomatic, part of the Temporal, and Mandibular bones.  In the figure 1 here, you can see all the bones except the palatine, because it's inside the mouth.

Notice that the nasal bones are connected to the frontal bone which forms the upper rim of the orbit, making the nose (straight foreface) above the eye, not level with the lower eyerim as stated in the "Illustrated Guide to the Standard".

The figure at the left is an unretouched photo (except for the dashed line) which demonstrates the relative positions of the nose, the straight foreface, and the eye

Now you might ask, what is that zygomatic arch doing stuck out there on the side of the face?  Mind you it is the FACE, not the skull we are talking about.  The skull or cranium is only the bony box which is basically a brain container, everything else is face.  The importance of that fact will become evident later.  In Figure 2, you will see a large muscle which joins the side of the skull to the lower jaw.  This muscle, the Temporalis, is one of two muscles which close the jaws.  The other one, not shown, is the Masseter.  It joins the zygomatic arch to the lower jaw.  So the purpose of the zygomatic arch is closing the mouth.  If this arch is weak or missing, the animal could not live.  This refutes the notion that the zygomatic arch is flattened or as the Illustrated guide puts it, "should be only slightly curved".  It is always, in all canines, and in all predators, for that matter,  markedly curved, because without it, the animal would be an unsuccessful predator, and soon be eliminated by evolution.  Only rats and animals like other rodents or ungulates who nibble rather than slice up prey have rather flattened zygomae, but Canines, Felines, and all the other predators like the weasels and bears have strongly curved zygomae to accommodate the massive temporalis muscle they need for predation.

We have defined "narrow", "head", and "skull", so what is so-called "backskull"?  There is no anatomical name for it so we are left to sort of guess what it is.  Are the people who use that term including the large, thick temporal muscle which clothes the posterior two thirds of the skull, or just the bony "skull" itself? Since the notion of "backskull" seem to refer to the bony skull rather than the soft tissues of the head one assumes it would include the back part of the parietal bones and the occipital bones.  So, if we accept that definition, in same sized dogs, are there different widths of "backskull"?  The simple answer is NO!  Remember what the skull is: a simple brainbox. The shape of the skull is dictated by the shape of the brain because in the fetus, the skull bones begin as soft membranes surrounding the brain. Rather late in fetal development, bone is laid down in this membrane and becomes the bony cranium or skull.  Through selective breeding we have been able to deform the facial bones of the dog to produce all manner of oddities from the Borzoi to the Bulldog.  However, the canine brain is the same shape in all breeds from wolves on down.  We simply haven't had time to tinker with the brain: 40.000 years is an instant in evolutionary time.  The brain refuses to assume a different shape - it is not as genetically malleable as the facial bones.  So in all dogs of a similar size, the brain, hence the skull, retains the same shape and size.

Look at figures 3 and 4.  Here are the skulls of a  coyote (35 lbs.) and an apso (17 lbs.) photographed side by side.  At first glance, the coyote looks much larger.  But look again.  The difference is almost exclusively in the facial bones and some of the muscular attachment ridges on the skull.  The skull itself which encloses the brain is almost identical in size and is identical in shape.  The "backskull" of both are the same.  Now any canine whose backskull were truly narrow would be unable to remain upright.  Why?  Because the part of the brain located in the "backskull" would have to be underdeveloped in order to develop a deficient "backskull".  That part of the brain is the "Cerebellum" whose function is balance and motor coordination.  A canine with a truly narrow (as compared to normal canines) backskull would be non-viable because it would never have been able to walk..

So there you have it, a few myths debunked: the lower eyerim level nose, the "slightly curved" zygomatic arch, and the "narrow" backskull.  And I haven't even addressed any of the things an apso IS - only what it IS NOT and could never be .  And the reasons for these "is not" 's are well understood and universally accepted facts of canine anatomy.