If I were you, I wouldn’t start from here …

How on earth did I end up writing a blog about algae and the generally unfashionable end of biodiversity?   Of all the possible trajectories my career could have taken, how did I end up here?   I was recently asked to put together a career timeline for a British Phycological Society meeting. The idea was that if several experienced phycologists (e.g. the BPS Council) did this, then student members would have a better idea of what makes a successful career in algal research.

I fear that my career timeline does anything but set a good example to a novice phycologist. I showed the draft to one colleague who commented that the meandering nature of the timeline seemed wholly appropriate. I cannot disagree.   My PhD is on mosses, not algae; I did a spell of postdoctoral work on Mediterranean palaeoecology and I spent two years in Nigeria which was a fascinating place to work but definitely not the place to develop the strong publication list necessary to get an academic job in the UK.   My period of self-employment (the past 19 years) started with a series of fortunate coincidences rather than any decisive planning on my part.   I was reminded of the old joke about a tourist asking for directions to a particular town and a local scratching his head and replying: “well, sir, I wouldn’t start from here.”

Career_timeline_MKelly

My career “timeline” produced for the British Phycological Society meeting in Galway, June 2014.   A larger version is available here.

I was not at the meeting where these posters were displayed, which is a shame as I would like to have compared experiences. My guess is that the relationship between the early and late stages of an academic career is not something that can be predicted with any great degree of certainty.   The choice of supervisor and topic for a PhD, subsequent steps into postdoctoral work (is there a vacancy directly relevant to your PhD? Is, indeed, a sideways step to broaden experience more useful?), life choices (what if your partner has a stable career some way from the lab where you would like to work?) will all determine outcomes.   If this was a study on algae rather than on people who study algae, I suspect that most of us would be worried that there are too many variables that we cannot control to allow us to distinguish “signal” from “noise”.

One point about my career that had not fully sunk in until I prepared the timeline was that for two spells over the past decade I have been a part-time carer as well as a scientist. Two of my children have had ME/CFS-type conditions.   Each was at a different age when the illness started and symptoms in each case were very different. However, the consequences have been the same: much missed school, struggles to get qualifications, frequent hospital visits and, often, re-arrangement of family life and social commitments to fit around their needs. I have never kept notes on how much time my care commitments amounted to, but guess it to be between 10% and a third of my week, depending on the extent to which I can “cox-and-box” with Heather. Care, in both cases, would have been much more difficult if we both had conventional full-time jobs.

If I had to distil my timeline into a couple of sentences of pithy advice for aspiring phycologists, it would be this: plan as much as you like so long as you are prepared to tear up your plan every two or three years. If that sounds too negative, be assured that the life-changing event that you did not anticipate is more likely to be the making of you than any careers guidance you may be offered.   And my last word of advice: ignore unsolicited advice.

In praise of the Olympus TG2

A brief diversion to terrestrial habitats in order to praise my Olympus TG2 camera (see “Getting close to pearl mussels with my underwater camera…”).

The photograph below shows Orange Hawkweed (Pilosella aurantiaca) photographed by Heather on a recent visit to the North Yorkshire coast near Skinningrove.   The left hand image shows the flower head whilst the right-hand image is an enlargement of the same photograph showing individual stigmas on which you can see pollen grains. That’s a huge amount of detail for a single photograph, particularly as the depth of field available to the macro photographer is usually very small.

Pilosella_aurantiaca

Philosella aurantiaca, photographed on the North Yorkshire coast in June 2014.

Incidentally, what is the correct plural for “stigma”?   My trusty Wild Flower Key (Rose, 1981) says “stigmas” but diatomists use the same term to refer to isolated pore on the surface of a valve, and the plural for these is “stigmata”. This is also the usage amongst Catholics when referring to the crucifixion wounds of Christ. My Shorter Oxford Dictionary offers both “stigmas” and “stigmata” as legitimate plurals for six different definitions of stigma.   “Stigmas” grates on my ears, as my sub-discipline prefers “stigmata”.   However, as it is a very widely used botanical term, understood by many non-specialists, “stigma” is a de facto English word, rather than just a technical Latin term. As such, it earns an English, rather than a Latin, plural. That’s why BBC correspondents say “stadiums” not “stadia” and “referendums” not “referenda”. I guess, following that logic, “de facto” is a de facto English term as well? Oh, the joys of etymology …

An England fan in Vilnius …

Blogging has just got a whole lot more difficult as the laptop on which I usually write is also our principal means of viewing the World Cup.   Watching the matches has, however, sparked memories of previous world cups, some of which are vaguely related to the topics about which I write on this blog.

The last World Cup, in South Africa, doesn’t really fall into this category. My most substantial memory is, ironically, not watching a match.   We were at the Glastonbury Festival and chose (wisely, as it turned out) to see Ray Davies perform on the Pyramid Stage rather than go to the big screen to watch England v Germany. We were cheerfully singing along to “Sunny Afternoon” as England fans were converting en masse to become enthusiasts for goal-line technology and David James was picking balls forlornly out of his net

The 2006 World Cup coincided with a very busy period in the EU’s intercalibration exercise, which I have written about before (see “Still travelling, still thinking…”, “Remembering Jean-Gabriel”). I have my mobile telephone bill for June/July 2006 as a strange memento of that period, as it records calls from no less than seven different countries as I criss-crossed Europe (two, to be honest, were for calls from airport transit lounge and our visit to Portugal was no more than a quick hop across the border from nearby Vigo one evening for some sightseeing and a drink).

I was in Vilnius, Latvia, for a large meeting of national representatives involved in the intercalibration of rivers from across northern and central Europe. Each evening, small groups would peel off from the post-dinner gatherings in the hotel bar to go and watch their country play. On the second evening, it was England v Trinidad and Tobago and I headed into the old town of Vilnius with a colleague to find a sports bar showing the match.   The final 2-0 score line, as I remember, flattered England whose opponents that day included a player who I had seen a few weeks earlier turning out in a League One match against Hartlepool.

En route home from one of these trips I visited the Baltic Centre for Contemporary Art in Gateshead where there was an installation that consisted of a tunnel lined with TVs each tuned to stations from around the world.   The idea was that the dark tunnel full of these flickering images would provide a dislocating experience that emphasized the world’s cultural diversity. They had, unfortunately, chosen a bad time to display the installation as about three quarters of the television stations were showing the World Cup in one form or another. Instead of highlighting our differences, it had the opposite effect showing how, for that short period, the world was remarkably united in its preoccupations.

The perplexing case of the celibate alga …

Oedogonium presents a real challenge to an ecologist.   As I mentioned in my previous post, there are many species and these are found in a wide variety of conditions. In order to identify the species we need the reproductive organs but, as is the case for several filamentous freshwater algae, these are rarely seen in the wild. I did consult two colleagues on whether it was possible to induce Oedogonium filaments to grow these in the laboratory, but both told me that this was difficult. The theory is that you are more likely to find reproductive organs in situations where the alga has been allowed to dry slowly.   This is a useful survival strategy as the spores are usually very resistant to desiccation and can survive long periods out of water. However, converting theory to practice is not straightforward.

But how, I wondered, was the section on Oedogonium in the Freshwater Algal Flora produced?   ‘From secondary sources’, came back the reply. In other words, the author of this part of the Flora had relied descriptions and illustrations in earlier publications. As the most thorough work on Oedogonium in the UK was performed by the Wests, father and son, in the late nineteenth and early 20th centuries, this means that there has been no thorough overview of Oedogonium here for over 100 years.   I searched the database Web of Science and found just 14 papers that reported studies on the taxonomy of Oedogonium in the intervening years.   Just two of these were from European laboratories: one in 1991 in Czechoslovakia and a Polish study from 1979.   That’s not very much, considering the large number of species and their very broad distribution.

Just as we can identify some flowering plants from their vegetative characteristics alone, so some people have tried to identify Oedogonium using just the properties of the filaments. However, there is not very much to go on, apart from the length and width of the cells. The best attempt is that by my colleague Susi Schneider in Norway (see “A brief excursion to Norway”).   She differentiated eight types of Oedogonium in Norwegian rivers based on cell dimensions and noted a significant relationship between these types and phosphorus concentrations in the rivers where they grew.   Interestingly, the narrow forms were associated with low nutrients whilst the broader ones were found in more nutrient rich conditions. The population I found in Stockerley Burn was relatively broad which suggests, using Susi’s criteria from Norway, that this is a nutrient-rich stream. I am, however, reluctant to import Susi’s categories directly to the UK because our rivers are very different from those in Norway. However, I think it would be interesting to see whether the broad principles could be used here, even if we needed a slightly different calibration.

These struggles with Oedogonium also suggest that this is a genus that would benefit from a molecular genetic study, which would be a much more powerful means of differentiating between forms of Oedogonium although, unless we cracked the secret of either finding or culturing fertile Oedogonium it will be difficult to reconcile the DNA results with classical taxonomy. Until then, I fear, Oedogonium, represents yet another case of the “trailing edge” of science, where we may be in danger of forgetting faster than we learn.

Reference

Schneider, S.C. & Lindstrøm, E.-A. (2011). The periphyton index of trophic status PIT: a new eutrophication metric based on non-diatomaceous benthic algae in Nordic rivers. Hydrobiologia 665: 143-155.

A case of mistaken identity?

Imagine, just for a moment, that someone makes a list of the plants growing in a river or any other aquatic habitat and includes a category called “unidentified dicotyledon”.   Most botanists would throw up their hands in horror. Yet they probably have a category on their field record sheets for “filamentous green algae” which they use on a regular basis. It takes time, after all, to take a specimen back to the laboratory to check under the microscope and, let’s face it, the identification guides that are available are not very user-friendly and are full of unfamiliar terminology.

A slight variant on this particular sin is to record all the filamentous green algae that you encounter as Cladophora glomerata.  You are on a fairly safe bet here because a) it is a very common alga; and, b) no-one is likely to check.   However, there are a few algae that can be easily mistaken for Cladophora, especially if you are not paying close attention.

Last week, I did a survey of some streams draining into the River Browney, a tributary of the River Wear in County Durham.   Most showed evidence of enrichment which was not surprising as there were small sewage works, arable cultivation and a fish farm within these catchments.   And, as a result, it was no surprise to find that Cladophora dominated the stream beds at several sites.   One site, however, had thick wefts of filaments which looked and felt like Cladophora but, when viewed under the microscope, were quite different.

StockerleyBurn_BogleHole

Stockerley Burn at Bogle Hole,   About half the river bed is covered by thick wefts of filamentous green algae up to about 30 cm in length.

I found three different species of green alga entangled in these wefts. There was some Cladophora glomerata but the most abundant of the three was a species of Oedogonium (see “The River Wear in summer”), characterised by unbranched filaments and cap cells.   66 species of Oedogonium have been recorded from Britain and Ireland but we know little of their ecology. Whilst some forms are common in lowland, nutrient rich rivers and streams such as this one, I have also found Oedogonium in remote, low-nutrient environments such as the River Ehen in Cumbria.   It pays to be careful, in other words, and to make sure that your “Cladophora” really is Cladophora. The easiest way to do this is to check for branching using a hand-lens. If you can’t see branching in the field, take a specimen back to the laboratory and check it under a microscope. Some populations of Cladophora are much more sparsely branched than others, so you may simply confirm your original suspicions. Oedogonium is, in fact, a very distant relation of Cladophora, despite their similarity when viewed with the naked eye. Mistaking Oedogonium and Cladophora is equivalent to  confusing your best friend with a sea squirt (see “Who do you think you are?”).

More about Oedogonium in the next post.

Oedogonium_StockerleyBurn

Filamentous algae in Stockerley Burn: main picture shows the wefts of (mostly) Oedogonium; inset shows cells from a single filament with the cap cells arrowed (scale bar: 10 micrometres, 1/100th of a millimetre).

News about Batrachospermum … hot off the press

Two developments since I wrote my post on Batrachospermum (“Algae … cunningly disguised as frog spawn”): first, two of the images (my field view and Chris Carter’s microscopic shot) are going to appear in a book “Freshwater Life in South Africa” and, second, the genus Batrachospermum has been split into two.   This presents a slight problem as I no longer have the field material and so cannot determine whether the images are of true Batrachospermum or of the new genus Sheathia. However, as the book is intended for a lay audience, the nuances of red algae taxonomy can be sidestepped and, in any case, the key ecological “message” in this case is mostly obtained by recognising the genus (or, as we should now say, genera).

The paper is Molecular and morphological evidence for Sheathia gen. nov. (Batrachospermales, Rhodophyta) and three new species by Eric Salomaki and colleagues and it can be found in the latest issue of the Journal of Phycology (volume 50, pages 526-542).   It is a very neat study, collecting specimens of Batrachospermum from all over the world and subjecting these to molecular analyses. The outcome was a molecular “tree” that indicated quite clearly that one group of taxa within the genus was genetically quite distinct from the others.   So far, so good, but do these genera have any characteristics other than just different DNA?   The answer turns out to be that the main axis of cells in Batrachospermum is composed of cylindrical cells whilst that of Sheathia is a mixture of cylindrical and bulbous cells. Although red algal taxonomists already knew that there was a group of Batrachospermum species with this property, it was only when the morphological and molecular evidence was combined that there was a strong case for splitting these off into a new genus.

Seven species of Batrachospermum are listed in the Freshwater Algal Flora of the British Isles. Of these, three have now been transferred to Sheathia.   As I said in my earlier post, genus level identification is usually adequate for the purposes of general ecological assessment, so most of our current records will not allow us to differentiate between these two genera. The ecological notes in the Flora are not particularly helpful but do suggest that there is quite a lot of overlap in the preferences of the various species, so I doubt whether this split will result in a change in the way we interpret data. On the other hand, as we re-organise our synapses to accommodate this change, maybe someone will have a flash of inspiration to prove me wrong.

Oh yes, and I will need to update my lecture notes too.

A peer review of peer review

I had a paper published last week which was notable for two reasons: first, it was the culmination of about three years work on a project to ensure consistent application of a European Directive across the EU, and second because it was the first time that I had complained to an editor about the quality of a peer review.   The paper was entitled Comparing aspirations: intercalibration of ecological status concepts across European lakes for benthic diatoms and had a total of twenty co-authors representing twelve different countries. I do not pretend that it was a perfect manuscript and, indeed, hammering out a consensus with so many points of view on offer inevitably leads to loose ends that are hard to tuck out of sight. But one of the two referees appeared to me to have an agenda that went beyond an impartial evaluation of the paper.

Now I have recently had the task of finding peer reviewers for a special issue of Freshwater Science that I co-edited and I know that it is a thankless task.   People who I thought were the best suited to evaluate papers turned out to be busy, ill or otherwise unavailable. I had to cast the net wider to find individuals with enough specialist knowledge to assess the work and, in many cases, send out reminder emails to make sure that they completed their reviews within a reasonable period.   My own experience of having papers peer reviewed is that the process nearly always results in a better paper, simply by having two or three dispassionate readers commenting on it, but it is not perfect. I also read enough papers that seem to have slipped through the peer review process with serious flaws to make me wonder if peer-review really is giving us the gold standard of papers that is often claimed.

One big conceptual flaw lies at the heart of peer review: Thomas Kuhn outlined it in The Structure of Scientific Revolutions in 1962 when he argued that science advances by episodic leaps that he described as “paradigm shifts” rather than by the gradual accumulation of facts and evidence. He used the replacement of Ptolemaic astronomy by the new ideas of Copernicus and others as a case study, noting how the flaws in the old theory of the sun and planets orbiting the earth had been accommodated by making the calculations of planetary motion more and more complicated and it needed the radical thinking of Copernicus to provide the paradigm shift which, coincidentally, resulted in a much more straightforward set of calculations.

My concern is that, for a very conservative discipline such as that within which I work, the likelihood of getting a referee, or even two, steeped in “Ptolemaic” thinking is greater than getting a Copernicus.   Indeed, most of the mid-career onwards scientists who form the backbone of the peer reviewer community will have made their careers within the “Ptolemaic” paradigm. Of course, for every Copernicus there were probably a dozen wannabe paradigm busters whose work deserved to be rejected and it is probably better that peer reviews default to the conservative option. But, at the same time, peer review can also serve to reinforce the conservative position.

In my case, the editor reached her own opinion which was favourable to our paper.   The rogue reviewer’s comments were rambling and poorly reasoned and, indeed, many of his (or her) criticisms were, in fact, already answered elsewhere in the paper. So I guess that the system worked in the end. In any case, for all its faults, I cannot think of a workable alternative to peer review so I guess that we are stuck with it for the moment. I do sometimes wonder, however, how Copernicus would have fared if the publication of his treatise depended on a favorable judgement by two or three reviewers steeped in Ptolemaic thinking.