Lower Oesophageal Sphincter

When I was first studying the anatomy and physiology of the digestive system, there was no such thing as the lower oesophageal sphincter. Now all of the textbooks seem to mention it. The prevailing view, in my student days, was that food entering the stomach was prevented from returning up the oesophagus (reflux) by the acuteness of the angle at which the oesophagus entered the stomach. Despite there being numerous sphincters associated with the alimentary canal, one place where one was not to be found was at the gastro-oesophageal junction. It was even remarked that this might seem surprising. This, of all places along the alimentary canal, was a place where a sphincter would be decidedly advantageous and might be expected to be found.

Times have changed. Now the lower oesophageal sphincter does exist—if the textbooks are to be believed. Now it is often known simply by its abbreviation, LOS.

There is a related story about an old, rather curmudgeonly professor of mine. A guest speaker would be invited to give a talk to the staff and students of his department on the first Tuesday of each month during term time. A colleague was charged with the task of sending out invitations and making all the arrangements. The speaker was left with the details of their talk—title, topic, etc. Story has it that on one occasion, the speaker’s topic strayed into the area of the lower oesophageal sphincter, which he began to describe. There being no such structure in the anatomical canon at that time, the professor apparently rose to interject. He is reported to have risen and pointed out that “We don’t teach this here” and, turning to the audience, said, “Students, please ignore what this man is saying.”

I was not witness to these events. It was a story that entered department folklore before my arrival. As reported, the story is to characterise the professor’s rather brusque personality. Having experienced it, I can certainly attest to his brusqueness. However, I find the story a little difficult to believe in the form that it is related. In the time I was in his department, Prof. was always courteous to the visiting speakers. If something like this story did happen, I suspect that he may have interjected in a more polite way than department folklore remembers. He may instead have interjected to counsel caution about what at that time was not in the textbooks or in any of the regular teaching. We must remember that we were teaching medical students and that that would have a bearing on their later careers—not to mention the lives of their patients.

Looking at the most up-to-date edition of Grey’s Anatomy available about that time shows that there was only a footnote about sphincters in the lower oesophagus having been found in a few primate species so far studied. There was no such structure accepted at that time.

The Mind of a Human Biologist

Following my ‘First Anniversary' post, this would be a good time to mention more about the mentality I bring to this blog. My undergraduate degree was in Human Biology, as studied at the University of Surrey. There the course and department flourished between the 1970s and early 1980s, but now neither exist. Its demise began in the early 1980s with university cutbacks. Deemed more economically viable, an undergraduate nursing degree program ultimately took Human Biology’s place.

Interestingly, while the course did exist, no strict definition of the course title was ever given. What ‘Human Biology’ was, or how it should be understood, was never strictly prescribed. Whether it was a deliberate decision to remain uncommitted to a strict definition of ‘Human Biology’ is unclear. However, I think that this lack of definition was ultimately a good thing. We were left as students to discover what human biology was—and what it could be—for ourselves. Furthermore, whatever it was was not necessarily the same for every student. The course had many different and quite diverse facets. Each of us was allowed to develop our specific interests to the full. Each of us was a human biologist in our own particular ways. That is not to say that some commonality did not unite us.

There was a book that might be called the ‘book of the course.’ That was Human Biology (Harrison, Weiner, Tanner, & Barnicott. Oxford: Clarendon Press, 1964). Even though that book considered many of the facets of the course, it gave only a flavour of the breadth of our course. More importantly, what it gave was a sense of the ethos of the course. Nowhere was this better set out than in the Foreword written by the Nobel Prize-winning biologist Sir Peter Medawar (1915-1987). In it he describes how he understood human biology. It is worth quoting from it extensively. Medawar suggested that...

    "Human Biology is not so much a discipline as a certain attitude of mind towards the most interesting and important of animals. Human Biology portrays mankind on a canvas that serves also for other living things. It is about men rather than man: about their origin, evolution, and geographical deployment; about the growth of human populations and their structure in space and time; about human development and all that it entails of change in size and shape. Human Biology deals with human heredity, the human genetical system, and the nature and import of the inborn differences between individuals; with human ecology and physiology, and with the devices by which men have met the challenges of enemies and of hostile environments. Human Biology deals also with human behaviour - not with its wayward variations from one individual to another, but rather with the history and significance of, for example, family life; of love, play, showing off, and real or sham aggression. Finally, and most importantly - because most distinctively human - it must expound and explain the nature, origin and development of communication between human beings and the non-genetical system of heredity founded upon it."

(NB Writing in 1964, we must allow for how he refers to ‘men’ and ‘man.’ While it does not sound inclusive, human beings in every manifestation are included. If that were not implicitly the case, then Human Biology would be worthless.)

Reading for a degree, one does not usually read books from cover to cover. One typically omits prefaces, forewords, etc. It was only some years after graduation, when studying Medawar’s philosophical thought for a Master’s dissertation, that I bothered to read that foreword. Ironically, it was only then that I read a description of what I had already found to be the case for my undergraduate course. I am particularly drawn to the sentence, “Human Biology is not so much a discipline as a certain attitude of mind towards the most interesting and important of animals.”

Human Biology then is a way of thinking about ourselves.

First Anniversary

This post marks the first anniversary of me starting this blog. I would like to thank all those who have dropped by and read my various musings.

The turn of the year also offers me a good opportunity to remind myself about what I am doing… or think I am doing. Fortunately, I have a ‘What to expect’ statement of intent in my first post. My intentions remain largely unaltered, but I do not rule out development in unexpected directions. (Even directions as yet unknown to me!) I find that as I go along, there are certain things I’d like to share that are well suited to the blog format and other things that are not. Fortunately, I appear to have plenty of the former to be going on with.

The aim of this blog is to share things from my former academic life that cannot be shared in any other way. Otherwise they would vanish. I wonder what would have happened to these musings were it not for the invention of the blog and the blog format. I wonder how much has been lost of the musings of our forebears because they lacked such a vehicle. Even if some of the things I share are of minimal (possibly no!) value, I hope they are worth a quick read and a wry smile before they are forgotten.

Some might be worth remembering, though. At the end of a lecture many years ago, a student approached me and asked if I’d taught a girl called Sarah. I said that I had and that I remembered her very well. ‘I thought so,’ the student replied. ‘She taught me this subject on an access course I did before coming here. All the interesting and funny stories you’ve been telling, she now tells!’ I was deeply flattered.

If you, the reader, can use anything from these blogs, then please do so. I would be delighted if they were to find a new lease of life elsewhere.

Reminder: I continue to post on the 3rd, 11th, 19th, and 27th days of each month. This was an additional anniversary post.

What sort of science?

Is science only about finding things out? Or are there problems or puzzles that we are trying to solve? How often do we stop to wonder at what sort of enterprise we are engaged in? We imbibe how to do science over a long period of time beginning at school and going on to various levels at university. After university, it may take other particularly practical forms. If we are involved in a problem or puzzle solving version of science, exactly what is it that we are trying to solve? Engrossed in the practical elements of research, we may sometimes overlook our precise goals.

Consider the puzzles in newspapers or magazines or those in the apps on our smartphones. Some people naturally gravitate towards number puzzles, some to word puzzles others to more strategic puzzles like chess. The variety of considerable. As a species we are ‘solvers’. It is is sometimes suggested that our inquisitiveness is what gave rise to science. I suggest that our desire to ‘solve’ played a large part too.

I have used the words ‘problem’ and ‘puzzle’. In philosophy there is a distinction to be made between them. Problems are substantive by nature and, as a result, carry a certain importance. Puzzles are primarily linguistic by nature and rely on how words are used. (This is further complicated by the fact that a word’s meaning may shift over time.)

Ludwig Wittgenstein (1889-1951) claimed that in philosophy there were only linguistic puzzles. Sir Karl Popper (1902-1994) did not hold that opinion. Popper was asked to address the matter in a paper entitled "Are There Philosophical Problems?" at a meeting of the Cambridge University Moral Sciences Club on 25 October 1946.

At that meeting, he appears to have applied thinking akin to that characteristic of that for which many scientists know him. It may be expressed as follows:

• The question "Are There Philosophical Problems?" is itself a philosophical problem (it is clearly not a linguistic puzzle).
• Thus, there is at least one philosophical problem.
• Therefore, philosophy does not consist of linguistic puzzles alone.

This is a key theme in Edmonds and Eidinow’s book ‘Wittgenstein’s Poker’ first published in 2001 (and which I can highly recommend reading). 

Some puzzles are solved by putting the pieces together. A jigsaw puzzle is an obvious example. All the king’s horses and all the king’s men set out to do something akin to a jigsaw puzzle when trying to put Humpty together again. Since it did not work, that approach was clearly the wrong one. Reconstructing Humpty is problem not a puzzle. 

When trying to understand the human body scientifically, we are engaged in a process of taking the body apart and then not even trying to put the pieces together again. This deconstruction is, of course, done conceptually. Even if we were allowed, we could not take a living organism apart and it put it back together again alive. An organ may be surgically exposed and experimented upon. It is technically possible to remove an organ from the body and return it at another time. But we cannot expect to do this to several organs at once.

If we are going to deconstruct the body conceptually, we must find a way to reconstruct it conceptually, too. One way of doing this may be to move away from simply seeing organs as separate components of specific physiological systems and looking at how they work together with others organs - not least those in other systems.

A simple example is that of the heart and lungs and the way in which they work together. Typically they are addressed quite separately: the heart is described as part of the cardiovascular system and the lungs as part of the respiratory system. A textbook may describe them many pages apart and yet anatomically they are side-by-side and physiologically they have complementary roles with regard to respiratory gas transport. A conceptual linkage of the two is already done by teacher and student in and out of the classroom. There are other possibilities and there is scope for a more formal recognition of this type of thinking by textbooks.

Another diagram of the same - but different

Continuing my theme of diagrams of the circulatory (or cardiovascular) system and how they differ while representing the same thing, here is a picture from an old edition of Grant’s Method of Anatomy. (I think it is the 7th edition from 1965.) This book is still in print - although some diagrams have been modernised. I do not know how this diagram is currently being presented but there is sure to be one. A diagram of the course taken by the blood around the body is (that is, has become at some point) obligatory for textbooks.

To access other pages in this series, click ‘The Circulation’ (or the label of the same name) for the list so far.

As always, observe the similarities and the differences. In short, ‘compare and contrast’ each diagram with the others. You might also like to ask ‘Which diagram best suits my interests or requirements?’ Diagrams must provide sufficient information and not too much.

Improving upon Humpty

Humpty, having fallen from his wall could not be put back together again. Neither, for that matter, could his fragmented parts be reassembled into an alternative, viable Humpty. This is something that the nursery rhyme did not explore. Perhaps it is something nursery cannot do. However, we can at least raise the idea.

This leads, in turn, to the question of whether a new and improved Humpty might be made from his fragments? In some respects, this was the premise behind the 1970s television series ‘The Six Million Dollar Man’ and its sequel ‘The Bionic Woman’. To make such a Humpty requires not only what is left of his original parts but additional artificial parts engineered to exceed ordinary levels of human performance.

Prior to his accident, might we have been able to turn Humpty into a bionic Humpty 2.0? And, if we could, could we do this without removing any of his healthy parts? To remove healthy body parts, even for purposes of personal improvement raises ethical problems.

Organisms have two named aspects: their genotype and their phenotype. Genes get a lot of attention for a range of understandable reasons. We frequently hear of genes if not of genotypes. We almost nothing of phenotype but we are more accustomed to them than to genes. This is because these are what we see of people. We never see a genotype as such but a phenotype is how people are. Phenotype is derived from the Greek φαίνω (phaínō) meaning 'to appear, show'. Our phenotype is how we appear. It is what our bodies look like.

However, as humans our phenotype is not confined or restricted to just our bodily form. Phenotypes are extendable in a variety of ways. Richard Dawkins’ book ‘The Extended Phenotype’, first published in 1982, popularised the idea that phenotypes were more than just bodies. He gave a number of examples from the wild. When trying to attract mates, many animals do not rely on their bodily appearance alone. One classic example was that of the bowerbird and the elaborate habitats it creates. In essence, a bird able to make such an attractive construction must be worth mating with as it will contribute good quality genes to our potential offspring. Genotypes are reflected in the phenotypes they produce. The better the genes, the better the phenotypes. This also applies to the extensions those phenotypes give to themselves.

We are able to extend our phenotypes in other ways - and for reasons unconnected with mate choice. For example, using a walking stick to make up for injury or frailty is a phenotypic extension. Tools are phenotypic extensions. The more one looks the more one finds. Every aid to modern living is a phenotypic extension. Depending upon how we use them, they may indeed improve upon what or how we are.

Typically these are extensions to our phenotypes not replacements for parts of our phenotype. Where joints are replaced surgically the usual aim is restore the function previously enjoyed. It does not seek to exceed it. But why not?

Prosthetic limbs are also engineered primarily to restore lost function although it is possible to include an extended range and style of movement. For example, the wrist joint for a prosthetic hand might be given the ability to rotate a full 360 degrees. Even so, the desire to remove an uninjured hand simply to obtain this functionality is hard to imagine.

Whether this will always be the case is a moot point. If prosthetic hands could be engineered to have all the current functionality of a natural hand and more, might people of the future be tempted?

One way in which Humpty might have been improved upon - that is, guarded against the devastating injuries he suffered in his fall - might be to have given him a 'zorb'-like protective suit.

A Poor Question?

When biology emerged as a distinct science in the early nineteenth century there was a change of focus. Previously the study of living things was undertaken alongside the study of everything to be found in the natural world. This formed the field of natural history.

The phrase is continued in the name of a number of venerable museums. To this day, the displays in museums of natural history encompass things from the whole of the natural environment and sometimes beyond. Meteorites, for example, can also be seen in these museums. Although they have come from outer space, they landed on the Earth and, having entered our natural world, belong to the purview natural historian.

Here the name ‘historian’ should clarified. It does not refer somebody who has studied past events. Many of the exhibits in museums of natural history are about things from the past. Fossil skeletons are popular exhibits. This may give the impression that the ‘history’ in natural history relates to the past. Instead, the word ‘history’ has its origins in the Greek word ‘historia’, which means "inquiry, or knowledge gained from inquiry".

One of the scientific questions that early biologists thought they would be able to resolve was ‘What is Life?’ Attempting to answer this question has yielded a variety of answers and limited dividends as far as that specific question goes. What we have learned from the attempt has been how difficult it is to define. Faced with such a difficulty, the focus of biologists has become directed towards the characteristics and features demonstrated by living things rather than life itself.

But, is the difficulty the question itself? ‘What is life?’ may be a hard question to answer but it may also be a poor question to ask. When asking questions, it is advisable to ask what those questions mean? And to ask, whether they even make any sense? Importantly, we should have a notion of how the question might at least be addressed and where the answer may lie.

At a museum of natural history we can look at exhibits and tell immediately which were once living and which - like meteorites - never were. Yet we cannot provide a formal definition of life. This may also be the fault of what we require of a formal definition.

One may change to more meaningful questions like ‘What is life like?’, ‘What are the common characteristics demonstrated by living things?’ etc. Questions like ‘What is life about?’ do not, on the surface, seem very scientific. However, upon careful consideration may be more scientific than ‘What is life?’

We may address the question ‘What is life about?’ in a materialistic way by suggesting that life is about, what may be called, the Darwinian imperatives: Survival and Reproduction. Organisms strive to survive at least until they have performed a reproductive act. (For some insects, of course, the male is eaten in the act!) This opens up a rich field of intellectual inquiry. How one understands the organism and its component structures is then seen in the light of these twin imperatives and the parts played in survival and reproduction.

There are, of course, other ways of addressing the question ‘What is life about?’ I think of these as complementary, rather than alternative, ways of addressing the question. There is no single way of addressing this question to the exclusion of all others.