Category Archives: Pollination

A (bird) book for bedtime (and a bit about bees besides)

Biodiversity as it’s generally defined and conceived includes not only diversity of species and habitats, but also diversity within species, often (but not always) genetic in origin. Eddie Izzard’s new two-part television series Meet the Izzards neatly captures the idea of genetic diversity, and how it informs our understanding of the past evolution and prehistorical dispersal of a large, bipedal mammalian omnivore. “Cultural biodiversity” in Homo sapiens is less easy to define in this way as it has probably only a limited genetic component and is passed from individual to individual by copying and refining. Other species have “culture”, for example New Caledonian crows and chimpanzees, but human cultural diversity is more varied than that of any other species.

Take book reading as an example. Some individuals of our species never read. Others read only one book. Incessantly. And then argue about what it means with others who read the same book. Other individuals gorge on a book a day or snack on one a month, or manage on a starvation diet of one per year. I’m a two book nibbler. Normally I always have a novel and a volume of non-fiction on the go. The novel is for last thing at night when I need to turn off my mind and do some easy reading; a few pages then it’s time to sleep. Nibble, nibble. The non-fiction is for the morning, if I wake up early enough, or weekends if they are free; or train journeys. Still nibbling, but this time on more solid fare.

As with all cultural diversity, none of this is inflexible and at the moment I’m also reading a non-fiction book at night: Fighting for Birds: 25 years. in nature conservation by Mark Avery, former Conservation Director of the RSPB. Mark kindly came to give a talk at the university recently and brought copies of his book to sign and sell. It was a stimulating lecture and feedback from the students who attended was very positive. For those students who didn’t make it (and there were a lot) I have to ask: why are you paying thousands of pounds a year to not turn up to events that will inspire, educate and develop you? You had the chance of bending the ear of a very prominent British conservationist. At the very least you could have asked: “How do I get to do the job that you do?” You’re currently investing a LOT of money in your future and, frankly, wasted opportunities such as this are the equivalent of failing to claim a share dividend.

Back to the book. Although Mark claims Fighting for Birds is not an autobiography, it is very autobiographical in scope and provides some great personal insights into the RSPB and the development of bird (and broader) conservation in the UK and the EU. His description of the battles fought over the fate of the Flow Country brought back memories of writing an essay on that topic during my undergraduate years in the late 1980s. I’ve still not visited that part of Scotland but I have in mind a road trip this summer that may take it in. The RSPB is one of our partners on the Nene Valley Nature Improvement Area project so I was particularly interested in finding out more about what makes our most important wildlife charity tick. Mark is an engaging and candid writer, forthright in his opinions political and ecological (and their interactions) as you can see from his blog.

By pure coincidence, this week Mark hosted a guest blogger in the shape of Matt Shardlow, Chief Executive of Buglife, talking about the current controversies over banning the group of pesticides known as neonicotinoids. Matt puts forward a compelling case for withdrawing these chemicals from general use. I don’t dispute anything he says about the role of neonicotinoids in bee deaths (though there is some debate about dosage levels used in some of the published studies and how this might translate into effects in the field). But it does concern me that this new focus on pesticides is taking the spotlight off habitat loss, particularly grasslands, which is a far more important threat to pollinator populations. There is a real danger that this single issue will be seen as an easy fix by government when a broader reform of farming practices is what’s really required. The decline of wild bees and other pollinators can be tracked back to long before the introduction of neonicotinoids. There were some silly comments on the blog about neonics currently being the single most important conservation issue. This is short sighted hyperbole and (again coincidently) Lynn Dicks has written an interesting piece on the subject of rhetoric, lies and over-the-top claims in the journal Nature.

The decline and extinction of pollinators in the UK has been an ongoing process since the 19th century. I’d hate to see the government think that it’s “fixed” the pollinator problem by banning some pesticides, a much simpler task than protecting and restoring habitats, and encouraging farmers to manage their land more sensitively. With 70% of the UK’s land dedicated to farming, human (agri)culture has got to be a key element in conserving biodiversity.

Waxwing winter

2 Replies

January has been a month of biodiversity firsts for me.

First New Year celebrated with Karin in our new home, quietly with friends and kids, plus the cats and chickens that are part of our personal biodiversity. I’m going to write a lot more about this notion of “personal biodiversity” later this year, but in short, we’re all of us directly connected to biodiversity physically and in the space we inhabit at home and work. Think about that next time you’re devouring a pot of Activia or watering the spider plant in your office.

The first paper (hopefully of several) from Sam Tarrant’s PhD thesis has finally been published in the journal Restoration Ecology online ahead of the print version. In this paper Sam compares the pollinator communities and available floral resources on restored landfill sites to those on nearby nature reserves. The landfill sites are just as good for pollinators as the reserves, a surprising finding that parallel’s Lutfor Rahman’s results in relation to bird communities on restored landfill sites . All of which has implications for how landfill sites might be managed after they have fulfilled their primary function. Opportunities for biodiversity conservation sometimes come from unexpected sources.

Another first was discovering some of our research cited in the recent United Nations Convention on Biological Diversity’s progress report on the International Initiative for the Conservation and Sustainable Use of Pollinators. We were very pleased to see our work getting that kind of exposure on the international stage, regardless of what one may think of the Convention on Biological Diversity. The CBD is not without its critics as I recounted the first time I blogged, live from a CBD-associated scientific conference in Germany. This was later published in Bulletin of the British Ecological Society as “Blogging from Bonn“.

And I achieved a first by finally (after several years of trying) seeing a flock of waxwings (Bombycilla garrulus) a bird that, whilst not uncommon, is one which you really have to be in the right place at the right time to observe. They are highly mobile and never in one spot for very long. A friend of mine who is a very keen birder and has been trying for 25 years to see them and only achieved that birding tick this year. One of our graduates, who blogs by the pseudonym of the Hooded Birder, has some great images of waxwings – take a look and you’ll see just what a beautiful bird this is, very exotic looking for a winter visitor to Britain.

At this time of year waxwings fly down from Scandinavia like avian vikings, marauding through the countryside devouring fruit from trees and shrubs such as rowan, hawthorn, apple, rose and any many others. It’s quite a sight to see a bird the size of a starling eating large rose hips in a single swallow. They are very approachable birds and we got quite close to them. Some years are marked by massive irruptions of these birds and are termed “waxwing winters”. The latest data from the British Trust for Ornithology suggest that this is one such year and the Northants Birds site has regular reports of their appearance around the county.

Although I’m not by any means a serious birder, bird watching falls into the category of cultural/spiritual ecosystem services that is clearly supported by biodiversity. Birding organisations are popular: the Royal Society for the Protection of Birds has over one million members and financial resources of almost £100 million, for example.

This weekend the RSPB will be running its regular Big Garden Birdwatch, a great example of citizen science in support of biodiversity monitoring. I’ll do my hour of watching on Sunday morning; the current cold winter weather has brought birds into the garden that are normally found out in the wider countryside. No waxwings yet but I live in hope.

Thank the insects for Christmas (reduce, reuse, recycle part 2)

1 Reply

The university term has drawn to a close in a flurry of activity as we complete our pre-Christmas teaching and assessments, and the Department of Environmental and Geographical Sciences conducted a successful five-yearly Periodic Subject Review of its degree programmes. I’m conscious that some of the things I wanted to write about since my last blog entry have slipped past without action, including a week that was bookended by visits with students to iconic localities on the biodiversity and conservation map. These were a Monday trip to the Darwin Centre of the Natural History Museum in London with students on my final year Biodiversity and Conservation module; followed by a Friday visit to Wicken Fen, arranged by my colleague Janet Jackson for second year students on her Habitat Ecology and Management module. Both great days away from the lecture room, if for different reasons.

At the Natural History Museum we looked at the insect research collections, behind the scenes where the public does not normally venture. Wicken Fen, on the other hand, is open to all and we met birders and walkers as we toured the site. I kept a tally of the number of bird species we identified and the final count was 29 (30 if you include the chickens being kept in a back garden close to the visitor centre). It would have been impossible to make a meaningful species count at the Musuem as we were overwhelmed by the statistics presented by the curators: 85,000 butterfly and moth specimens in the Lepidoptera section, 3 to 4 million specimens of true flies (Diptera). On it went; wonderful diversity and an incredible scientific resource.

Which brings me neatly to the main topic of this entry: the importance of insects at Christmas! I’ve mentioned before that one of the intentions of this blog was to reuse some of the writing I’ve done over the years in various fora, sometimes updating and re-casting it ro reflect recent activities or events (hence the “reduce, reuse, recycle” epithet). The publication this month of the final report of the Government-sponsored workshop Insect Pollinators: Linking Research and Policy in which I was involved has prompted me to modify and re-post an entry that first appeared on the University of Northampton’s blog at this time last year.

The social and economic news is not great, global poverty is on the increase even in the richest countries and the range of human-influenced assaults on the natural environment seems to be escalating on a weekly basis. But at least it’s Christmas! A time to relax and enjoy ourselves, to share time with family and friends, and to unwind during the cold and gloom of winter. Whatever your faith, or lack of it, Christmas should be about taking a break and reflecting on the year that has passed. We’re helped in that respect by the ceremonial seasonal trimmings: the Christmas tree, strings of flashing lights, baubles and tinsel. So while you’re kissing a loved one under the mistletoe, admiring that glossy holly wreath, or tucking into your Christmas dinner, spare a thought for the insects.

“What in Saint Nicholas’s name” you are asking ”have insects got to do with Christmas?!” Well, like the turkey, we’d be stuffed without them: they play an essential part in providing us with the things we associate with the Christmas. If we had no flies, wasps, bees and other bugs acting as pollinators there’d be no berries on your mistletoe or your holly. Kissing and admiring would be a less festive affair and that’s just for starters. These insects also pollinate many of the vegetables, herbs and spices on your plate, as well as some of the forage that went to fatten your roast bird or tender joint of meat. Not to forget much of what went into the nut roast that’s feeding the vegetarian relatives.

The economic value of insect pollination in the UK was estimated by the recent National Ecosystem Assessment to be about £430 million per year . In fact this is a huge under valuation because the labour costs alone of paying people to hand pollinate those crops would run into billions of pounds. This sounds far fetched but it’s already happening to fruit crops in parts of China. The answer is to encourage wild insects, not artificially managed honey bees, because collectively the former are far more abundant, and often more effective, as pollinators. Their diversity is an insurance against losing any one species in the future.

The NEA’s valuation is also too low because it only deals with edible crops. Mistletoe and holly are both dioecious species, which is to say that individual plants are either male or female, as is the case with most animals. This means that the plants cannot self pollinate and insects are absolutely vital to their reproduction and to the production of the decorative berries we so value (a holly wreath without berries is just a big spiky doughnut, in my opinion). Whilst researching the economic value of the annual mistletoe and holly crops for this blog posting I’ve been having a conversation with Jonathan Briggs over at Mistletoe Matters and he tells me that “the mistletoe trade in Britain is entirely unregulated and not documented in any tangible way” and the same is true of holly. We therefore have no idea what the economic value actually is. But some back-of-the-red-and-gold-Christmas-lunch-napkin calculations can at least give us an insight. Auction reports this year show that on average the best quality berried holly was selling for £2.50 per kg whilst equivalent quality holly without berries cost only 75p per kg. In other words, pollination by insects increases the value of that crop by over 300%. Similarly the high quality mistletoe averaged 80p per kg, whilst the second grade stuff was only 20p per kg. And the best holly wreaths (presumably with berries!) were averaging £3.40 each. These are wholesale prices, of course; retail cost to the customer is much greater. A decent holly wreath will set you back between £15 and £30 whilst online shopping for mistletoe is in the £5 to £15 bracket. The national census of 2011 shows us that there are 23.4 million households in England and Wales, plus there are 2.36 million in Scotland and 0.70 million in Northern Ireland. Let’s round it down and say there’s 26 million households in the whole of the UK. Let’s also be very conservative and estimate that only 5% of those households bought one holly wreath and some mistletoe at a total cost of £20. Multiply that by the small proportion of households buying these festive crops and you arrive at a figure of about £26.5 million! And that doesn’t include non-household use in shops, offices and businesses. So there you have it: an industry worth a few 10s of millions (at least) all being ultimately supported by insects.

With pollination, timing is everything, and Jonathan also made the point that spring flowering mistletoe and holly can be important early nectar sources for insects. Therefore despite the poor summer weather, this year has been a good one for mistletoe berries because the pollination happened before the heavy rains began. Despite being quite common plants, rather little research has been done on either holly or mistletoe pollination in the UK and it would make for an interesting student project.

The Landscape and Biodiversity Research Group here at the university is playing its part by working to understand the ecology of plants and pollinators, and how to best conserve them. In this blog I’ve referred a few times to some ongoing projects researching how the wider landscape is supporting pollinators in habitats such as country house gardens (Hilary Erenler’s PhD work which she’s currently writing up) and urban centres (ongoing PhD work by Muzafar Hussain). There’s also the recently completed work by Sam Tarrant and Lutfor Rahman on pollinator (and other) biodiversity on restored landfill sites. Plus work that’s only just started by Kat Harrold on how whole landscapes support pollinators in the Nene Valley Nature Improvement Area. This is all part of a broader programme of research into the conservation of biodiversity in our region and beyond, including a contribution to the Shared Enterprise Empowering Delivery (SEED) sustainability project. Biodiversity matters and its importance to our society is being increasingly recognised by government, business and the public.

So if you make one New Year’s resolution on the 31st December, let it be that you will put away your bug sprays for 2013 and learn to love the insects (even wasps!) who give us so much and help to support our economy in a very real way. It costs us nothing; all we need to give them is well managed, diverse, unpolluted habitats in which to live.

Have a great Christmas everyone!

When is a yucca not a Yucca?

9 Replies

Notice the difference? The italicisation and capital initial of the second Yucca. That’s how the genus name of a species should be formally presented in a scientific paper, or in a newspaper article, or wherever. Like Homo – the genus in which our own species (Homo sapiens) sits.

It might seem like a narrow and pedantic point, but it’s important. Accurate and descriptive naming of species, genera, families and other taxonomic ranks is crucial to those of us who study biodiversity and is at the core of our science: without names for species, for example, we cannot make informed conservation judgements or comparisons between habitats in relation to which species are present or absent. Names matter.

But it’s not just the names themselves, it’s also how they are presented which is important: when I see the words yucca and Yucca in print, they signify two different things to me. The word “yucca” is an informal name for a group of plants that is widely applied by gardeners and has no formal scientific status. Yucca on the other hand refers to a very specific group of plants and has a clear meaning to a biologist.

To give you an example of this I’ll first have to introduce you to the Northamptonshire Natural History Society (NNHS) which was founded in 1876 and must be one of the oldest surviving local natural history societies in the country. Some important 19th Century scientists were honorary members, including Charles Darwin, Thomas Huxley and Joseph Hooker. This perhaps reflects Northampton’s proximity to London though there may be other factors: one could compile quite a long list of scientists with links to Northamptonshire.

The Journal of the Northamptonshire Natural History Society was first published in 1880 and continues to the present day. Which brings us back to yuccas. Last year a short article by a NNHS member summarised the local weather conditions in Northampton for each month of 2010 (J. Northants Nat. Hist. Soc. vol. 45, no. 1). December of that year was a particularly cold month and the author notes that “the species of Yucca trees planted in Northampton, which although thriving in recent years, were killed by the cold period”.

Strictly speaking Yucca refers to plants of a particular group which are endemic (i.e. only naturally occurring) to the New World. The genus Yucca is a member of the asparagus family (Asparagaceae), subfamily Agavoideae. The plants which suffered so much in the cold winter of 2010 are in fact New Zealand Cabbage Trees (Cordyline australis) which, as the name suggests, are endemic to New Zealand. The genus Cordyline is also a member of the family Asparagaceae but belongs to the subfamily Lomandroideae and is therefore only distantly related to Yucca.

The leaves and stems of Cordyline and Yucca do look very similar, hence gardeners tend to use yucca as an informal name for both. However when these plants flower it is clear that they are very different. Flowers of the various species of Yucca are typically quite large and are adapted to pollination by a very specialised group of moths which lay their eggs within the flowers. The reward for these moth pollinators is a brood site for their caterpillars, which feed on a proportion of the developing seeds of the Yucca plant. In contrast the flowers of Cordyline australis are small and produced in very large numbers in dense inflorescences. They are also highly fragrant, to which anyone who has grown one of these plants to maturity in their garden can testify. The fragrance attracts a range of insects which feed on the nectar produced by the flowers and so pollinate them in the process. It is these differences in flower structure, more than characters of stems and leaves, which taxonomists use to classify such plants.

Until recently large New Zealand Cabbage Trees were a feature of many front gardens across Northampton. Some particularly fine examples were to be found along the Kingsthorpe Road between Osborne Road and Balmoral Road. I suspect that the largest Northampton specimens were planted in the 1970s, perhaps because people wished to recreate something of the exotic feel of package holidays to Spain and Portugal. Following the freezing weather of December 2010, the growing tips of most of Northampton’s New Zealand Cabbage Trees were killed and the top growth gradually withered and died. I was sad to see this happen to my own plant, a medium-sized specimen that I had rescued from a skip at the University several years ago, and which had become well established in my garden. However later in 2011 my plant, and those in neighbouring gardens, re-sprouted from its deep tap root and started to produce multiple rosettes of leaves around the base of its dead trunk. Give it a few years and Northampton gardens will once again be crowned by these exotic imports from the Southern Hemisphere. I moved house in early 2012 and wasn’t able to take my rescued plant with me, but I have a feeling it will survive many more cold winters to come.

Names matter to biologists, indeed to scientists of all types. They signify and tell us things beyond just the words themselves. To give a very personal example, a few people have asked me why I chose the title “Professor of Biodiversity” rather than “Ecology” (my main area of training, though confused in some peoples’ minds with New Age philosophies); or “Biology” (a much broader designation than I feel comfortable with); or even “Pollination Ecology” (narrow, to the point, but too restrictive). After a LOT of thought I chose “Biodiversity” because it very broadly reflects my interests in the whole of Earth’s life forms, the interactions between these species, and how they come together as assemblages, communities and ecosystems. But I’m also interested in the history of our understanding of biological diversity and this title gives me scope to pursue those interests too.

It’s all in the name.

The Great eSCAPE

7 Replies

As I begin to write this blog entry, there’s a buzz of voices around me, excitedly discussing future research or past results, or saying goodbye to friends and colleagues, old and new. It is the last day of SCAPE 2012, the annual meeting of the Scandinavian Association of Pollination Ecologists (or “for Pollination Ecology” or “for Pollination Ecologists” – the name seems to have drifted over the years). SCAPE was the first overseas conference I attended, as a young and enthusiastic PhD student, in 1991. Older but no less enthusiastic, SCAPE is for me a regular fixture in the calendar. Even if I can’t always attend, I try to send my good wishes to the organisers, with a promise to be there the following year.

SCAPE was founded in 1986 as an informal get together of Swedish research students who were all broadly interested in questions of pollination ecology. Since then it has been held every year, maintaining the informal organisation and circulating between Sweden, Denmark, Finland and Norway, which is the venue for this year’s meeting in Skjærhalden in the beautiful Ytre Hvaler National Park. Attendance in recent years has varied between 50 and 80 participants, peaking when it’s one of the 5 yearly anniversary specials. One of the many great things about SCAPE is that it’s a very friendly, open hearted conference at which new research students rub shoulders with established researchers, and can present their provisional research findings safe in the knowledge that they will receive constructively critical feedback. Those established researchers can expect to have their conclusions challenged, as good scientists should, but it’s never done with malice.

The talks this year have spanned the usual wide range of geographical localities (Brazil, Israel, Spain, Ireland, as well as Scandinavia), scales of research focus (from the genetics of self incompatibility to landscape scale assessments of pollinator diversity), and quality of presentations (overuse of laser pointer on text-dense slides to textbook examples of how to deliver a message in 15 minutes).

Although I enjoyed the whole meeting and gained new knowledge from every presentation, there have been some talks which really stood out for me because I appreciated the overall approach, the message that was being delivered, or the insights it gave into questions I’d not previously considered. These include Dara Stanley’s estimate that bumblebees from 800 different nests were foraging on a single field of oil seed rape; Achik Dorchin’s account of the staggering number of bee species in small habitat fragments in Israel (totalling more than in the whole of Britain); a dissection of the question of when pollination can be a limiting ecosystem service for crops by Ignasi Bartomeus; and Robert Junker’s initial account of the huge diversity of bacteria associated with different flower organs. There were many others I enjoyed, of course, but that gives a taste of how diverse the subjects were.

Although I wasn’t speaking this year, two members of my research group were: André Rodrigo Rech talked about his PhD work on pollination of Curatella americana in Brazilian savannahs; and Stella Watts presented some of her postdoctoral work on honey bee versus unmanaged bee pollination in an endemic Iris species in Israel. This last work was undertaken with Amots Dafni, one of the doyens of pollination ecology. Amots attended the conference and told us he’d finally decided, in his 68th year, to retire from formal university teaching, administration and supervising research students – and begin a new project! Enjoy your “retirement” Amots!

Karin attended SCAPE with me and enjoyed scientist-watching, a hobby that gives me frequent insights into how we work as a community, and gives her insights into what makes me tick. Half a day of travel saw us back home at 2am Monday morning; I then had to be in university for a 9am seminar with students on my final year Biodiversity & Conservation module. Despite being tired the seminar went well, perhaps fuelled by the post-conference buzz I usually feel after these events. The seminar finished early to enable me to drive up to Park Campus, the university’s other site, for a brief meet-and-greet with the head of Sandtander Universities and his team. Banco Santander’s higher education arm has been funding scholarships and research activities at the university for several years now and it was a small grant from them that enabled André to attend SCAPE. Seemed only polite to say thank you.

A highlight later that week was Thursday, which was taken up with our annual first year undergraduate trip to Oxford Botanic Garden, part of my module Biodiversity: an Introduction. I also wrote about this in March but for the current academic year we have brought the trip forward. Our visit was hosted by the superintendent, Timothy Walker, who engaged the students for an hour as we walked the gardens, covering everything from the medical importance of plants such yew trees (Taxus spp.) in providing treatments for cancer, to the importance of specific trees for two Oxford writers, JRR Tolkien and Phillip Pullman. Timothy also described how much of the planting is laid out in beds according to plant families as defined by the latest phylogenetic research the (APG III system) stressing the importance of modern systematics to understanding biodiversity. If you want to know more about this, Timothy wrote and presented a recent television series called Botany: A Blooming History which remains the best account I’ve seen of the history of plant taxonomy and why it is relevant to modern plant sciences.

That evening Karin and I attended the opening of a show at the university’s gallery called “Encounters with Drawing” by artist Angela Rogers. There’s some very thought provoking material in the show and I recommend a visit if you are local and have time – it runs until 30th November. We chatted with Angela about the “drawing conversations” she has with people and some of her comments about “how much space do individuals need” chimed with familiar ideas from ecology about intra- and inter-specific competition in organisms and niche theory.

I’m going to end this entry with a link to a video post by my friend K.-D. Dijkstra (who I introduced in an earlier blog). It’s not often that the actual moment that a species new to science is discovered gets captured for everyone to see, but here’s K.-D. doing just that!

Lend us a Darwin?

Scientists Must Write (and Speak and Listen and Review and Edit)

4 Replies

“Scientists Must Write” was the title of a book published back in the late 1970s by a former tutor of mine, Robert Barrass, at what was then Sunderland Polytechnic (now the University of Sunderland). I had assumed the book was now a long gone publishing memory and no longer available. But it turns out that Robert updated it in the early 2000s and it’s still in print. Almost 30 years (30!) later I can clearly remember Robert impressing upon us the importance of good writing skills for scientists-in-training. At the time I was as far from being a professional scientist as it’s possible to be and so didn’t fully grasp this, but nonetheless what he said chimed with my own notions that writing was important, even for a scientist.

Nowadays I realise that it’s not just the writing of standard, academic papers, book chapters and books which is essential: writing of all kinds is a necessary facet of the life of a research active scientist. This June sees the publication of two contrasting articles that illustrate this point. The Royal Horticultural Society’s journal The Plantsman has published a piece entitled “The Importance of Native Pollinators“, whilst the historical journal Notes and Records of the Royal Society has published my paper on “John Tweedie and Charles Darwin in Buenos Aires“. Neither of these is standard academic fare, at least for me. The first is a popular article aimed largely at gardeners and others interested in understanding more about pollinator conservation. The second, whilst academic and rigourously peer reviewed, is primarily historical rather than scientific.

Why am I writing popular conservation articles and historical papers? Largely for different reasons, though they are linked by my overall fascination with biodiversity. The Plantsman article is an example of taking ideas and findings from the LBRG‘s research and presenting it to a wider audience who might, at the least, find it interesting and hopefully useful. One might describe it as “popular science” though I don’t really like the term: it suggests that it’s somehow different to “real” science, which is not the case: it’s really only the format of the presentation which is different.

The John Tweedie/Charles Darwin paper reflects my desire to understand where our scientific knowledge of biodiversity comes from. As scientists and conservationists, we draw conclusions about species’ distributions, conservation threats, extinctions, and so forth, based on information from specimens that have been collected by people like Tweedie and Darwin, and curated at places such as Kew and the Natural History Museum. By its nature it’s a historical process and historical research helps us to understand how we arrived at our current understanding. The only reason we know that 23 species of bee have gone extinct in England since about 1800 for example, as I cite in my Plantsman article, is that over the past two centuries specimens and observations have been recorded and analysed. This is an ongoing process, exemplified by the BWARS project mapping the spread of Bombus hypnorum the most recent addition to the UK’s native bee list.

As well as writing we scientists gain much from listening to what others in our field have to say and a well attended, and very interesting, meeting in London last week launched the British Ecological Society’s Macroecology Special Interest Group . The range of talks spanned community structure, interaction networks, ecosystem services, latitudinal gradients and disease biology, all at the large spatial and temporal macroecological scales covered by this subdiscipline of ecology. Or is it really a multidisciplinary field, a merging of old fashioned biogeography with more modern ecological approaches? Who knows, perhaps this is sterile semantics; as I mentioned to one of the organisers in the pub afterwards, “macroecology” seems to me to be more about a philosophy of approach rather than a field in itself.

Formal teaching has largely finished for the time being, so in addition to research activities and university administrative work, much of the remainder of the last couple of weeks seems to have been taken up with editorial and peer reviewing duties for journals, including PLoS ONE, for which I’m an academic editor. This can be time consuming and thankless, but is absolutely vital if the whole system of scientific publishing is not to grind to a halt. Scientists must write, but that writing is supported by a body of individuals who act as peer reviewers, editors, proof readers, and so forth. Collectively that eats up a lot of scientist-hours and is something we should never take for granted.

The Roof Tiles of Chirche (Darwin’s Unrequited Isle part 3)

4 Replies

Architectural analogies in evolution are not new. The most famous (and, in its time, controversial) is perhaps Gould and Lewontin’s “Spandrels of San Marcos and the Panglossian Paradigm” in which these prominent evolutionary biologists suggested that some features of the biology of species were secondary “emergent” structures which formed from the conjunction of other, evolved characteristics. That is to say these features are not evolved in their own right, they are simply by-products of the evolution of other factors. In this respect they are like “spandrels” – the ornamented space between two structurally significant elements, for example the arches and the domed roof they uphold in the Basilica di San Marco in Rome. Gould and Lewontin were following a metaphorical path that had been traversed by many major figures in evolutionary biology. Most notably, Darwin used the notion of the architect, contrasting natural with artificial selection, in a number of his books, including “The variation of animals and plants under domestication”.

Another architectural analogy occurred to me over the past couple of weeks, time Karin and I have spent back in Tenerife pursuing field work funded by a small grant from the British Ecological Society. We are staying in a cottage in the pretty village of Chirche in the west of the island. The older properties, our rented castita included, are roofed with traditional, hand made rough clay tiles that are slim, curved and tapering towards one end. Tiles are carefully laid curve up and curve downwards in alternating rows so as to both shield the building from the weather and to shed the rain from the roof in the channels formed by the up-curved rows. These same tiles are used along the ridges of the roof, in contrast to roofing back in the UK where differently shaped tiles would serve for roof and ridge. Not only that but the same basic curved and tapering form serves as a structural element for the tops of walls, as half pipes to direct the flow of water, and as building blocks for chimney stacks, etc.

It’s a wonderful example of economy of manufacture and purpose, using the same basic element to serve multiple functions. What has this to do with biodiversity you ask? It’s a fitting observation for this trip, in as much as we are studying flowers and their visitors. Flowers are another great example of the economy of evolution: all of their basic elements (male stamens, female stigma style and ovary, petals and sepals) have evolved from the same basic botanical element – leaves. If that seems unlikely take a look (a really close look) at some of the fancy, highly bred flowers for sale at your local garden centre or plant nursery. Some will have leaf-like structures deep within the flower where genetic mutations have resulted in the expression of organs rather more like their ancestral form than like stamens or petals.

The purpose of returning to Tenerife is to collect more data as part of an on-going project I’ve been running within our undergraduate field course. The Canary Wallflower (Erysimum scoparium) has flowers that change colour; they are pure white when they first open and from the second day onwards they darken to violet then ultimately purple, staying on the plant for up to 10 days. At the same time the flowers stop producing nectar. The pollinators learn to associate white flowers with more reward and focus their attention on the newly opened blossoms. This is clearly an evolved strategy as it benefits the plant to have its most recent flowers preferentially visited, rather than the older flowers that have already received pollen.

In an earlier paper we demonstrated, by removing purple flowers from experimental plants, that these older flowers act as a long-to-medium range advertisement to pollinators (the plants look purple from a distance). It’s a very intriguing system. We now have about 10 years of data showing that the main pollinator is an endemic solitary bee (Anthophora alluadi). But there seems to be some variation between years, with a wider range of different bee species present in years following very dry winters (such as this one) when there are fewer other plants in flower. So the idea that we are testing is that the relative specialisation of the plant (i.e. how many pollinator species it has) is context dependent: in some years/sites it is a specialist, in others a generalist.

Biodiversity is not fixed in time or space. It varies at all scales and, for this plant and its pollinators, the biodiversity of interactions between them is stable only over modest time periods. Over the millions of years these plants and bees have existed in the Canarian archipelago, their exact roles within the system have probably varied enormously, like actors improvising their parts dependent on the whims of external forces, in this case weather conditions. The roof tiles of Chirche saw little rainfall during the last winter; bad for the local farmers and the other people who depend on this rain. But good for ecologists wishing to study how variation in climate can affect biodiversity.

There’s a reason why toilet seats are curved

1 Reply

The recent announcement of a study showing a correlative link between the loss of biodiversity and the decline of human cultural diversity (specifically of local languages) reminds us once again that studying biodiversity is more than just about discovering how many species there are in different geographical locations and how they can be conserved. The remit of biodiversity covers all levels of biological organisation, from genes to species to ecosystems, including the human species and those ecosystems we have created for ourselves. Not only that, biodiversity is also about why species occur where they do and how they have adapted to their local conditions, including interactions with the other organisms that shape their ecology and evolution.

Plants and pollinators are a good case in point: if there is not a suitable size or morphological fit between flower and animal, the animal will not be able to obtain its reward and the flower will not receive pollen. Both immediate ecological context (which species are present in a community?) and longer term evolution (how have these species adapted to one another?) are important in this regard. These thoughts were very much on my mind as I sat uncomfortably on a rectangular toilet seat in a very swish hotel in Switzerland last week. There’s a reason why toilet seats are usually curved: it fits the usual shape of our arses. Rectangular toilet seats are not well adapted to their role and do not work effectively: they are uncomfortable and a victory of Swiss style over human functionality. The same applies to the convex saucers on which breakfast coffee was served. They were the anthithesis of biological adaptation where the stylish patterns of a butterfly’s wings, say, have evolved for a purpose (display and/or camouflage) rather than to look pretty.

Karin and I were in Switzerland at the invitation of Nadir Alvarez from the University of Lausanne. Nadir and his group are using the latest molecular techniques to carry out fascinating research on species interactions and patterns of phylogeography, including work on one of my favourite groups of plants, the genus Arum. At Nadir’s request I gave rather a broad talk on the theme of the ecology and conservation of plant-pollinator interactions in highly managed landscapes, focusing on the work that members of the LBRG have done in Northamptonshire and adjacent counties. The questions afterwards suggested that it generated quite a lot of interest in the audience of about 50 faculty members, postdocs and research and MSc students. Before and after the lunch hour talk I spent time chatting with postgrads and staff about their research projects, moving from office to office in a carefully Swiss-timed fashion, always conscious that outside each window were fantastic views across Lake Geneva to the snow crowned Alps beyond: “You forget it’s there after a few weeks” claimed one postgrad.

Lausanne is a lovely city which is enhanced by the human-contrived biodiversity of planted roofs, green walls, and public green spaces. And by the species which naturally colonise suitable habitats, such as the moisture loving mosses and algae which have found a home in the stone and steel fountains designed by Georges Descombes in La Place de la Louve.

Back in Northampton late Friday night, then up early Saturday morning to prepare a talk for the local branch of Friends of the Earth’s Bee Cause campaign launch. It was the usual general over view of what pollination is, why it’s important, why pollinators are declining etc., etc. I pointed out at the start that the public audience (once again of about 50) were getting a free taster of what, from September 2012, our students will be paying £8,500 per year to listen to. They seemed to enjoy it and had some interesting questions afterwards, though one guy claimed my talk was too long and “a bit like being in church”. This was the same individual who asked me whether “wasps and nettles can sting each other” which perhaps gives an insight into his world view.

Back at the coal face of university life this week, however, the dominant theme has been marking student work. Lots of of it, as we work to get final grades into the system prior to exam boards in early June. A pile of about 90 first year reports on woodland community structure, based on field work we carried out last autumn, has been hard work but in many ways enjoyable. Some of these students have done very well and really engaged with the aims of the assignment. Quite a number independently found a recent study on the importance of rot holes in trees for maintaining epiphytic lichen diversity. Has anyone looked at this in British oaks? It would make an interesting final year student project. Which brings us back to the links between biodiversity and human culture, because lichens have been used for millenia as sources of pigments for painting, for example in illuminated Saxon manuscripts such as the Lindisfarne Gospels.

Darwin’s Unrequited Isle (part 1)

8 Replies

A busy week of biodiversity-related activities terminated last Friday in a frantic rush to make sure everything was organised for this week’s field course in Tenerife. The field course has been running for 10 years and has proven to be both popular with students and productive, generating data for a couple of research papers, with more in the pipeline.

Tenerife is an extraordinary island as Charles Darwin recognised; it’s the place that Darwin really wanted to go to when he embarked on H.M.S. Beagle, though he never made it due to the Beagle having to be quarantined before anyone was allowed onto the island. The captain decided to sail away and Darwin was devastated. Hopefully the rest of his trip made up for it, but it’s interesting to speculate whether Darwin’s ideas about evolution may have taken a different path had he been able to visit the Canary Islands, in many ways an Atlantic analogue of the Galapagos……but I’m getting ahead of myself…..this week I hope (time willing) to post some updates about out Tenerifean activities. But back to last week.

The comments sections below the articles on the Times Higher Education Supplement are frequently mires of vile, obnoxious trolling that would embarrass even Shrek. However an interesting article by Alice Bell has raised a debate about what exactly it is that scientists (and other academics) should be writing. Widening science communication should also include giving talks about one’s work to a non-specialist audience. Which is exactly what I did on Wednesday evening when I spoke to an audience of 65 beekeepers, gardeners and farmers in South Warwickshire. They were very attentive and asked some insightful questions for about 40 minutes after I’d finished speaking, stopping only when someone mentioned that the tea and biscuits were ready. All told it was a 90 mile round trip through heavy rain but worth it for such an engaging audience.

Earlier that morning I had been interviewed by BBC Radio Northampton about a report that has just been released indicating that the “native” [sic] Black Honey Bee variety is more common in the British Isles than previously thought. Lovely. Good news for the beekeepers I told them. Now let’s pay a bit more attention to our 250 REALLY native bees, many of which have declined numbers, and 23 of which have gone extinct since 1800. Not to mention the butterflies (though there’s recently been some good news as far as they are concerned too) and the hoverflies and other pollinators.

Thursday was Think Tank day for the SEED project and I took part in the biodiversity session, which was ably chaired and coordinated by Gareth. It went as well as we could have wished and hopefully some concrete partnerships are going to come out of it. But ultimately it was a talking shop and biodiversity should be about doing and experiencing more than talking. Which brings us back to Tenerife.

On Monday we took the students up to the Guimar Badlands (Malpais de Guimar) a 40 minute drive north east from where we are staying in San Eugenio. I like to take students to Guimar on their first day in the field: the pine and laurel forests that we visit later in the week are physiognomically similar to such forests in Britain. But the succulent dominated xerophytic scrub of Guimar is utterly unlike anything that most of them have experienced previously. The field work we do at this site is always related to plant community structure, trying to understand how the biodiversity of the primary producers is “organised”. There’s lots of different ways to measure community “organisation” in an ecological sense, of course, and this year we are looking at how the plant community changes along a gradient from the strand line limit of the vegetation, inland and away from the salty influence of the sea. It’s an exercise I’ve wanted to do for a while because it’s always been clear that the plants DO change; we’re just never put numbers on it. So we ran out four 120 metre transects and identified all of the plants that they intercepted at 5m intervals. Lots of student frustration as they used a combination of identification keys, hints from me and guesswork to put a name to these unfamiliar species. But by the peak of the day’s heat in the mid afternoon we had a data set and several sunburned students [no matter how often you mention the word “sun block” there will always be some who think they don’t need it].

Back at our apartment complex there was time for a rest/shower/power nap, depending on your preference, before we reconvened to enter the data into spreadsheets and start generating some graphs. And these preliminary data look really good, showing how the salt tolerant halophytes are replaced by the various euphorbias and other species that dominate the rest of the Badlands within about 40m of the lower limit of the vegetation, with other species even less salt tolerant and only making a show after about 90m. This is biodiversity doing interesting things………

Tuesday was a trip up through the pine forest zone to Las Canadas at the foot of Mt Teide. A long day through some spectacular scenery, interspersed with collecting data on bird behaviour at a picnic site and checking some populations of an endemic plant the Canary Wallflower (Erysimum scoparium). Interestingly the populations to the south of Las Canadas have more or less failed to flower this year, probably because of the very dry winter on Tenerife. Many other species have also not flowered and there are some implications for the pollination biology of this plant which I’m hoping we can quantify later in the week. Will report back when I get a chance………..over and out for now.