There are a few characteristics of textbooks on anatomy and physiology that need to be recognised lest they go unnoticed. Recognising what is missing from teaching, why it is missing and how, despite its absence, it may still be important must be identified.
Including everything pertinent to the anatomy and physiology of the human body in one textbook is unfeasible. Thus, one reason why something is missing is lack of space. Another reason is to do with the approach textbooks habitually adopt. Textbooks on anatomy and physiology have a typical style and approach.
Firstly, these textbooks concentrate on adults. There is little or no content relating to how adults come about. There is little or no content relating to embryology, prenatal or postnatal development. If these subjects receive any attention, it is necessarily limited.
Teaching embryology comes after adult anatomy. That is not surprising. Embryology can be rather intricate. However, teaching anatomy from an embryological perspective is a potentially creative approach. It adopts a synthetic rather than analytic approach. It builds the body rather than dismantling it.
Life history is divisible into three phases (rather than the seven ages in Shakespeare's As You Like It). These can be called pre-adult, adult and post-adult. Roughly, they are the pre-reproductive, reproductive, and post-reproductive phases of our lives. Just as the pre-reproductive phase is missing, so is the post-reproductive phase. The bodily changes that occur with ageing are also largely ignored. These changes are not necessarily pathological or associated with disease. These changes are not abnormal. They are changes experienced by all.
The adult bodies in textbooks are always healthy. Significantly, textbooks on anatomy and physiology are primarily concerned with normal, non-pathological and healthy adult bodies. But what that is is not clear. There is no single simple agreed definition of what constitutes healthy. (Similarly, there is no single simple agreed definition of what constitutes diseased.) Normal and healthy are terms used loosely. They are used synonymously and even interchangeably. What a standard or 'normal' body is is never stated.
Anatomically, there is considerable scope for variation - even anomalies - without adverse effects on the individual. What textbooks represent is an accepted canon. They overlook variations and anomalies. A tradition has built up about what is considered standard. Textbooks are written based on textbooks that have preceded them. The body depicted is what is now deemed canonical.
Similarly, there is little or no reference to evolution in textbooks on anatomy and physiology. As noted elsewhere, the theory of evolution makes all of biology intelligible. Evolution accounts for how we got to be how we are. It also provides the conceptual framework for understanding all biology. Variation is a feature of evolution. Without variation, there would be no anatomical or physiological change.
I mentioned above how there is often little or no reference to certain things that still need mentioning. A passing mention or brief paragraph noting these things does not necessarily qualify as sufficient attention. It is impossible to include everything that has a bearing on the body. To reiterate, recognising what is missing from teaching, why it is missing and how, despite its absence, it may still be important must be identified. We have only a partial picture of our bodies. That must not be forgotten.
