Saturday being a beautiful day of high summer, and faced with the choice of either writing this blog, or getting some fresh air and exercise, I decided to do both simultaneously, and walked the seven hills of Edinburgh while letting my mind roam free. On the way in, the traffic signs said, “Yellow warning: heavy rain expected”, but I hoped to get round before the deluge.
Depending on your choice of route, it’s a twelve mile walk with about 3,500 feet of ascent -something like a Munro with a long walk in. I like to start in the north-west with Corstorphine Hill which is a bit of an outlier. It’s sufficiently far out from the city centre that you can park your car without paying an exorbitant parking fee. Then I take in the seven, anticlock, in a broad circle: Corstorphine, Craiglockhart, Braid, Blackford, Arthur’s Seat, Calton, and Castle Hill. I walked west up Ravelston Dykes past Mary Erskine’s, the school rumoured to be the model for Muriel Spark’s The Prime of Miss Jean Brodie, took the lane that bisects Murrayfield Golf Course, and half an hour after starting I reached the radio mast, abeam Clermiston Tower, atop Corstorphine Hill, or, because it is fenced off, as near to it as I could attain. Then I left the hill in a southerly direction to cross Edinburgh’s main drag at Balgreen and head for Craiglockhart. I thought, what shall I write about? Write about something that nobody is talking about; write about the Mastodon in the Auditorium.
Last week, while clearing out a drawer in the never-ending struggle to offload junk, I came across an ancient essay I wrote under exam conditions in the fair city of Edinburgh, in First MB. Bacteria and Bacteriophage.
Bacteria are unicellular, prokaryotic, haploid organisms which replicate as quickly as once every twenty minutes. Thus they are potentially able to produce a vast number of progeny in a very short time. What happens in fact is that they very soon exhaust the medium in which they find themselves – in the lab, this might be a petri dish with a layer of nutrient agar on which the bacteria is (sic) initially placed, perhaps in colonies, or as a lawn across the total surface of the agar. Before all nourishment has been extorted from this medium, the bacteria will pollute their own surroundings by excreting poisons – say, alcohol – by diffusion. Thus the typical bacterial life-cycle is as follows…
(hand-drawn graphs follow)…
Poison enters the medium, growth stops, and often an equilibrium is attained, or the vast majority of cells die.
It occurs to me: here is the Mastodon in the Auditorium. We know it’s there; yet we pretend we don’t see it. Here is our essential predicament. Aside from the fact that a bacterium is unicellular and homo sapiens is multicellular, we are all inhabiting a petri dish of finite dimensions and finite resources.
(I took Balgreen Road and hung a right on to Gorgie. This is where you can get lost in the suburbs in a maze of streets and lose time. I took Chessar Avenue to Slateford Road thereby negotiating both Slateford Rail Junction and the Union Canal. Then I turned southeast at Craiglockhart Avenue and headed for Napier University. I crossed Colinton Road and passed the old Craiglockhart Hospital building, its frontage unchanged, where Wilfred Owen met Siegfried Sassoon during the Great War. Once again I left the hustle and bustle of the city traffic for the peace and tranquillity of parkland. It seemed that out of battle I escaped…) I went round the back of the Craiglockhart University Campus, found a gap in a hedge, accessed the path, and then abruptly turned left up a steep grass slope toward summit number two at Wester Craiglockhart.)
The Mastodon in the Auditorium is overpopulation. The petri dish is planet earth, and the bacteria, are us. Last month, the human population of the world was estimated to be about 7.62 billion. The population of the world is projected to increase in 2018 by 92,157,695. This means that the world needs to create a city of London, with all its amenities, goods and services, once a month. This is pretty startling, yet, so far as I can see, it is completely off the political agenda. You can see why. It’s dynamite.
(Next stop, Braid Hills. More subtle route planning. I cut down through the Merchants of Edinburgh Golf Course and emerged on to Greenbank Drive. It doesn’t look promising on the map, but there is a pedestrian pathway that allows you to cut through to Greenbank Road, then if you take Greenbank Park you can access another path that lets you cut through Braidburn Valley and up on to Comiston Road. Don’t be tempted to take Riselaw Road or Place, take the Crescent up onto Braid, cross over and enter Braid Hills via a bridle path that will take you up on to the golf course. There’s a trig point, which I touched, but I also went on to the radio mast which is the truer summit.)
Population Studies, for example from the United Nations Department of Economic and Social Affairs’ Population Division, boast a considerable literature, which is seldom reported. I’ve been listening to epidemiologists and public health gurus of one sort or another for a lifetime, but I can only recall one on the lecture circuit who made an impact with respect to overpopulation – John Guillebaud, the Emeritus Professor of Family Planning and Reproductive Health at UCL. That he holds the only chair in the UK in his chosen discipline suggests that Prof Guillebaud is out on a limb, perhaps something of a maverick. He spends a lot of time giving lectures on sexual and reproductive health to health professionals. He is an expert on contraception. He believes in contraception as a force for public good. I have seen him in a lecture contrasting two slides – one showing an array of contraceptive devices, the other showing an array of weapons, and asking which one is the more palatable way of keeping the population at a reasonable level. He thinks of contraception as a potential means of tackling the problem of the Mastodon in the Auditorium. I nearly said “controlling the population”, but Prof Guillebaud specifically asks us not to juxtapose the words “population” and “control”. To the western liberal democracies, any kind of state intervention in this regard is anathema. Article 16 of the Universal Declaration of Human Rights states that “men and women of full age, without any limitation due to race, nationality or religion, have the right to marry and to found a family.”
Prof Guillebaud is a patron of Population Matters, formerly the Optimum Population Trust. Other patrons include the broadcaster Sir David Attenborough, economist Sir Partha Dasgupta, biologist Prof Paul Ehrlich, and primatologist Dr Jane Goodall. Population Matters has called upon government to develop a sustainable population policy. In 2013, controversially, this body called for a UK zero-net migration policy, and the curtailing of child benefits to families of more than two offspring. These policies were abandoned in 2017. Here, tax relief benefits are available to parents. The Scottish Government has a flagship policy of doubling free childcare hours by 2020. Presumably this is so that both parents can go out to work.
(Blackford Hill lies to the north east of Braid but it is best to resist the temptation to make a beeline towards it straight across the golf course. You only get tangled up in a welter of broom. You can head for the club house and get back on the bridle path to a suitable point to cross Braid Hills Drive. Or, as I did on Saturday, take a slalom of paths through the Braid golf course with a more direct route on to Hermitage Golf Course. Now you need to cross the stream running through the wooded gully of Blackford Glen. Left, right, left, right, left over a footbridge, left again, right and upwards, and you’re into the skirts of Blackford Hill. Cross a meadow, through a gate, turn left and right, and ascend via wooden steps towards the Royal Observatory, round the shoulder of the hill to access the trig point from the south east.)
We might see ourselves as bacteria on the petri dish reproducing in vast numbers and polluting our environment so extensively that we can no longer exist in a toxic environment, and the environment becomes sterile. But of course it is not as simple as that. Even on the petri dish, it’s complicated.
Nonetheless, there may be in the culture of bacteria a single mutant which has immunity from the particular poison being excreted into the medium, and this mutant will continue to replicate and produce its own strain. If we think of the “poison” of the medium as being, not alcohol, but phage particles parasitic on the bacteria, then the same result is apparent. A culture containing, say, a billion bacteria, infected by five or six times as many phages, will be almost totally destroyed, but a handful of individual mutants may survive, unaffected by the phage.
Ah. The survival of the fittest. The strong over the weak. What a grim business.
This mutation was shown by Delbruke and Luria not to arise as a result of contact with phage, but to be the result of a random event which may happen in the absence of phage. Their proof of this fact – a demonstration by an indirect approach – has been verified by experiments involving replica plating. A mutation along the length of the single bacterial chromosome, happens to give immunity. Such an event can happen with probability of perhaps one millionth to one billionth, for a mutation at any particular gene location. If such a mutation does occur, the phage are somehow prevented from penetrating the bacterium and directing the DNA of the cell in the production of replica phage. In the more usual event however, a phage particle alights on the surface of the bacterium, the phage cylinder contracts and injects its DNA complement into the bacterium. Here, the phage DNA takes over control of the replicating processes of the bacterium, somehow overseeing its own replication. Several phage generations are reproduced, the cell lyses, and phage disappear out into the medium ready to attack more bacteria.
(Now run past the observatory and down to the bottom of Observatory Road and then – and this is important – don’t turn left, turn right. That’s the trick; then take first left on to Lussielaw Road, then it’s just a little jink across Mayfield on to Suffolk Road and Craigmillar Park Road. When Craigmillar Park Road changes its name to Minto Street turn right on to Salisbury Road and head for the Royal Commonwealth Pool.
I stopped for a diet Coke.)
So we have this scenario. A vast human population is running out of sustenance. The environment is being turned into a huge rubbish tip (Mr Trump is the only person in the world who doesn’t think so). Sea water levels are rising and land masses are diminishing. Vast numbers of people are on the move because the land is shrinking and because they are so impoverished anyway that their homeland holds nothing for them. The wealthy countries of the world see this emerging threat and are fast pulling up the drawbridges and dropping the portcullises, terrified that the defences are going to be broached by the teeming, marauding millions. In terms of political manifestos, drawbridges and portcullises seem to be the only options.
(Now for the biggest hill, Arthur’s Seat. From the Commonwealth Pool I crossed Powderhouse Corner and steered a course straight for the summit, crossing Queens Drive and leaving it at the Hawse, choosing a rough path above Hunter’s Bog. This took me to the path rising above Haggis Knowe and the remains of St Anthony’s Chapel. Then I had to dig deep for a steeper climb, to access the twin peaks of Arthur’s Seat from the North. Lots of tourists atop, with lots of languages in different accents. And what a view!)
I have a notion that the people holding the levers in charge of the drawbridges and portcullises think they have things under control. Yet the race does not always fall to the swift, nor the battle to the strong, but that time and chance happeneth to them all. How far can I push the metaphor of the petri dish?
(From Arthur’s Seat I headed north over to Calton Hill, dodging the tourists round Holyrood Palace and the Scottish Parliament, and instead slipping past Holyrood Abbey and Croft-an-Righ to Regent Park, Regent Terrace by the old Royal High School, St Andrews House, and thus on to the hill. I headed for the summit at Nelson Monument. Six down.
Sometimes, however, a phage enters a bacterium and does not kill the organism. But another sort of life cycle ensues. The genetic complement of the phage this time becomes attached to, and indistinguishable from, the genetic complement of the bacterium. Now the bacterium replicates as usual and a new strain is produced. Cell lysis can at this stage be induced, for example, by action of ultraviolet light. Phage within the bacterium acting in this way are known as prophage, and the phenomenon is called lysogeny.
So perhaps we can survive the cataclysm after all, but only if we are prepared to change, and to accommodate. I think I’ve stretched this metaphor to breaking point.
Back down off Calton I reached the east end of Princes Street and turned south on to North Bridge. I stopped at a Prêt for a Smoothie, and I couldn’t resist popping into Blackwell’s opposite Old College, but I didn’t buy a book. Then I retraced my steps to the Royal Mile and headed up past St Giles towards the castle. Outside the Camera Obscura there was a guy floating in mid-air. He was dressed in saffron robes and his only contact with the ground was through a slender stick held in a wizened hand. How do they do that? I’m a pushover for magic. The Castle Esplanade was fairly heaving but I slipped up the left side under the stanchions of the temporary seating for the International Military Tattoo, reached the castle moat, touched the wall, and thereby knocked off the seven.
Then the heavens opened. And I’ve still got a blog to write.