Thursday, 13 December 2012

Ammarnäs and Renforsen




         West of Ammarnäs (from obj.utsida.se)



In his brilliant book Fishing in Utopia: Sweden and the Future that Disappeared, Andrew Brown writes: “......where the mountains rise out of the forests towards Ammarnäs”. It must be one of the few references in an English book to the village of Ammarnäs in Swedish Lapland. I lived there for several weeks in the summer of 1975 and it was one of those places to which I felt I must return. Fortunately, I did the following year.

They were working trips, as I had been invited to join a group of Biologists from the University of Lund in an investigation of rivers draining from lakes, trying to find out why these habitats support huge numbers of insect larvae that capture tiny particles from the water flowing over them. Those Biologists were wonderful people to work with and we enjoyed spirited conversations, and spirits, but also worked hard on the field work. They were good times, but that wasn’t the pull of Lapland for me. It was the sense that one could find areas that very few people had visited and no-one could dispute that the region has great natural beauty. If you can fall in love with a place, that’s what I did.

Bordering Ammarnäs to the east is the Vindel River, un-regulated along its length, and with some dramatic cascades. It was to the Vindel River that I returned in the late 1990s to work with Björn Malmqvist, one of my friends from the Lund group of fifteen years earlier, who was now at the University of Umeå. We were still both interested in insect larvae and travelled much of the length of the Vindel on occasions, although our main interest was in the lower reaches and in cascades and in runs between the regions of white water. So many of the locations for our work were beautiful and I developed a special fondness for one of the cascades – Renforsen.

       Renforsen (from www8.tfe.umu.se)



When winter snow and ice melts in the mountains, Renforsen is a magnificent sight and the river sometimes goes over its banks here – even carving a new channel through the forest on one occasion. It is awe-inspiring and it’s impossible not to be impressed. I found it another place to which I had to return and was fortunate that I did many times. I never tired of visiting Renforsen and always looked forward to my first trip of the year with great enthusiasm. 

After working on the river, Björn and I would buy a cup of coffee in the cafe nearby, listen to the roar of the cascade and not say very much. Very sadly, those times will never be repeated, as tragedy struck when Björn developed a brain tumour and died two years ago. So now I have memories of a very special place and a very special friend and colleague with whom I spent time there. I don’t believe in souls but, if I had one, a part would contain the powerful and emotive effects of Renforsen.

Thursday, 6 December 2012

Rotifers, Henry Gosse and me




This image by Charles Krebs of Floscularia ringens was posted yesterday on the “Walking with Gosse” Facebook page by Dr Susan England of Clio Publishing. It is of a rotifer that lives in fresh water and builds a tube that acts as protection, support and a means of attachment. Looking closely at the image we can see the groups of cilia which it uses to produce a feeding current. The tube is composed of balls largely of detritus, which are stuck together and the balls maintain their integrity for weeks, Floscularia extending the tube to take it further out into the water as the individual rotifer grows. The whole is approximately 1 mm in length and we see only a small portion here.

Henry Gosse, the great Natural Historian and illustrator, was fascinated by rotifers and assisted C.T.Hudson in a two-volume monograph on the animals. Despite Hudson’s protests, Gosse insisted on his attribution as assistant and this was typical of the man. The two enthusiasts were really co-authors and Gosse contributed much of his own detailed research to the volumes. In looking at rotifers, as with other living creatures, Henry Gosse saw evidence of the power of God and His Creation and it filled him with a sense of wonder.

As an evolutionist, I have several points to consider:

Why are the cilia used for feeding arranged in bundles?

Rotifers have many cells but had single-celled ancestors which used cilia for locomotion and feeding. Through evolution, cilia of some organisms became more complex and the bundles seen in Floscularia may promote increased feeding efficiency. The pattern of bundles seems very similar in form across the corona (the transparent lobes), so what caused their development in the first place? Did all the bundles appear simultaneously?

Building the tube

Several groups of rotifers build tubes and the tube of Floscularia is unusual in being made up of balls, primarily of detritus. The photograph shows the location of the “ball-forming device” in the cuticle of the rotifer and its constituent tiny particles will be collected readily from the water by the feeding current. We often ignore the presence of organic particles in water, yet they are found in vast numbers and have many important roles in the functioning of aquatic systems. Once a ball is formed, and compressed to a certain size, the rotifer can then locate it on the tube and having a tube with a wall of spherical balls is a very efficient use of materials. How did the “ball-forming device” and tube-building evolve?

Why do the balls in the tube maintain their shape and how do the balls stick together?

As mentioned, rotifers collect small particles of detritus and other organic matter. Detritus results from the breakdown of the bodies of living things and also consists of material that passes from living things as waste products or exudates. There will also be many different kinds of microorganisms (bacteria, etc.) that are attached to the fragments of detritus and are important in breaking them down into smaller and smaller pieces. To attach, microorganisms exude polymers and these are “Nature’s glue”, often becoming free from the microbes which produce them. It is these polymers which keep the balls intact as they are difficult to decompose and there are many "sticky" contact points when the ball is compressed. The exudates are in the form of minute fibrils and the rotifer could not make balls without the previous evolution of exudates by bacteria.

Amazing, isn’t it? 

Do I have any idea how Floscularia developed all these modifications? – No. Do I believe that they evolved by changes in genes occurring over huge numbers of generations? – Yes. Is a God responsible? – I don’t know, but do not think so. Evolution generates such a sense of wonder. I’m right with Henry Gosse in having that feeling when looking at living organisms, but we would not agree on the reasons why we felt that way.

Thursday, 29 November 2012

Looking back on Academic Life



I was very proud to be made an Emeritus Professor of Biology at UCL after spending the last 23 years of my career there.

Those years were not all spent in one location, as there were several moves to different buildings within the campus, resulting from amalgamations and re-organisations. My last year was spent in a building away from the main campus as no rooms were available in the refurbished building occupied by my latest Department. That was rather good in a way as, although I missed chatting to some of my colleagues, I didn’t feel that I fitted in with the contemporary focus of Universities. My interests had always been in research and teaching, but with each on an equal footing; research fascinated me and enabled me to follow my muse, while teaching gave the chance to pass on my fascination. That approach to academic life is now old-fashioned and, to have been more successful, I should have dedicated myself more to writing grant proposals and networking with those who could help me in my career. Maybe that sounds like the thinking of someone who didn’t have the necessary drive and ability to succeed and there is some truth in that. I was never going to be a high flier in research, even though the citation for the DSc degree I was awarded in 2008 stated that I had “distinguished myself by research and learning”. My interest in research was much more in having fun with ideas and then testing them out.

I loved teaching. Each year there would be a new group of students and we could work together on various subjects. The students mostly seemed to like me letting all my enthusiasms show, and were even accepting of some of my rather eccentric impersonations of animal locomotion and behaviour. Having had no pedagogical training, I was free to use my own approaches in teaching, so the end-product was the result of a certain amount of trial and error. As Biology is to me a wonderful, wide-ranging discipline it was easy to be motivated and to motivate students. Even more highly valued that the DSc are the three Teaching Awards which I received from UCL (a record, I think).

While very few colleagues had any wish to attend Graduation, for me it was one of the highlights of the year. Not the dressing-up, as parading in academic dress was never one of my favourite activities, but the chance to say goodbye to a year group of students and to meet with their families. What a difference between their first few days at University and the polished products that were now in the “outside world”. What a pleasure it was to work with most of them, even those who didn’t much care for the subject in that way that I did.

Few parts of academic life brought more ups-and-downs than the behind-the-scenes job of tutoring. It was always something that I felt was important and I did what I could to support students who were not having the best of times. Sometimes there were failures, and I regret that I may have made some bad decisions or given poor advice, but there were a lot more successes. Not successes for me, as I was just a sounding board, but for the students who were able to fight through their difficulties. Whatever the rewards of research and teaching, it was the pleasure of seeing these students graduate that provided some of the best times of my career as an academic. It sounds mawkish, but it happens to be true.

Thursday, 22 November 2012

Looking at gulls – evidence of a God, or not?




                                         
                                                                                                                      [Image from thepokerbird.com]



Take a look at this picture of a gull. What comes to mind? Being “bombed” with faecal matter while walking along a promenade at the seaside, or putting up with loud and raucous calling when gulls squabble over discarded refuse? Or perhaps one is taken by its elegant colour scheme?

As I spent several years teaching animal locomotion, what I see in the picture is a near-perfect flying machine. The wings are aerofoils and, as long as air flows over them in gliding flight, they generate lift. This is because the wings have a convex upper surface and a slightly concave under side, so air has to travel faster over the upper surface causing a lower pressure. The gull is thus “sucked” upwards – just like aircraft wings operate, although birds were first in having this feature by quite a few years. Of course, the wings are also used in flapping flight, requiring powerful muscles, especially those used to depress the wing. When sufficient airspeed has been achieved, the gull propels itself using oscillations of the outer part of the wing, while holding the inner section relatively still, so that its aerofoil section is used efficiently. Explaining oscillation would require me to go into too much detail for this blog and, for that matter, so would explaining the mechanism of flapping flight.

Then there’s the shape of the body. The picture shows that the gull has a near-perfect streamlined shape thanks to its covering of feathers – but feathers of a different type to those of the outer part of the wing. The profile feathers allow the smooth flow of air over the body, so that turbulence behind the gull is very much reduced. This, in turn, reduces drag and thus conserves energy needed for propulsion. It means that the tail feathers can be used to deflect air and function as a rudder; and note the position of the feet – tucked up to ensure the smooth air flow is not badly disrupted. Profile feathers also create the shape of the wing and feathers of a third type down ensure that the gull’s high body temperature is maintained by acting as efficient insulators.

I could go on and on like this – and did during lectures but no-one can look at a gull without thinking that it is extraordinarily well adapted to moving through the air. For those who believe in Creation, all the features of the gull (and I’ve only mentioned a few here) are evidence of the power of God. For those who believe in evolution, there is the puzzle of how all the small stages that occurred in the transformation of a scaled reptile into the gull came about through mutations in genes. For atheists, it is a matter of chance; for theists, a result of something designed, just as for believers in Creation. Both theists and atheists are swept up in a sense of wonder at what they see. So, now comes a question. Is this sense of wonder identical in those that believe in a God and those that do not? If the answer is “yes” doesn’t that invalidate the argument of those, like Henry Gosse, who use such feelings as evidence of their God? Does anyone out there have any views on this?