Tag Archives: Nature

Ivy binds the landscape and bridges the seasons: a new article just published

If you check out the latest issue of Bees and Other Pollinators Quarterly you’ll see that, as well as having a piece on the forthcoming COP26 climate change meeting and what it means for pollinators, the magazine has also published a short opinion piece by me called “In Praise of….Ivy”. The magazine is currently in the shops or you can subscribe by following this link: https://bq-mag.store/.

Although it can be invasive and an environmental nuisance in parts of the world where it’s introduced, common or European ivy (Hedera helix) is clearly one of the most vital plants across its native range of Europe, southern Scandinavia and the Mediterranean. Its clinging stems bind the landscape and provide habitat for a diversity of creatures. By offering nectar at a time when there’s few other plants in flower, and berries at a crucial point in the winter, ivy bridges a food gap for both nectar feeding insect and fruit eating birds and mammals.

Ivy is a very popular subject for student research because it’s in flower at the start of the university academic year. In the past I’ve had several students carry out their final year projects using ivy to test ideas about pollinator effectiveness and plant reproductive success. Because the open, densely-clustered flowers can dust pollen onto any insect that visits, the most effective pollinators will vary depending on which are abundant at any time and place, and include various types of flies and bees, plus those much-misunderstood wasps!

Perhaps we should leave the final word on ivy to the Northamptonshire ‘Peasant Poet’ John Clare who wrote ‘To the Ivy’ in the early 19th century:

Dark creeping Ivy, with thy berries brown,

That fondly twists’ on ruins all thine own,

Old spire-points studding with a leafy crown

Which every minute threatens to dethrone;

With fearful eye I view thy height sublime,

And oft with quicker step retreat from thence

Where thou, in weak defiance, striv’st with Time,

And holdst his weapons in a dread suspense.

But, bloom of ruins, thou art dear to me,

When, far from danger’s way, thy gloomy pride

Wreathes picturesque around some ancient tree

That bows his branches by some fountain-side:

Then sweet it is from summer suns to be,

With thy green darkness overshadowing me.

Further reading

Bradbury, K. (2015) English ivy: berry good for birds. https://www.theguardian.com/lifeandstyle/gardening-blog/2015/feb/19/english-ivy-berry-good-for-birds

Bumblebee Conservation Trust (2021) Ivy mining bee: https://www.bumblebeeconservation.org/ivyminingbee/

Jacobs, J.H., Clark, S.J., Denholm, I., Goulson D., Stoate, C. & Osborne J.L. (2010) Pollinator effectiveness and fruit set in common ivy, Hedera helix (Araliaceae). Arthropod-Plant Interactions 4: 19–28

Ollerton, J. (2021) Pollinators & Pollination: Nature and Society. Pelagic Publishing, Exeter, UK

Ollerton, J., Killick, A., Lamborn, E., Watts, S. & Whiston, M. (2007) Multiple meanings and modes: on the many ways to be a generalist flower. Taxon 56: 717-728

Woodland Trust (2021) Ivy. https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/plants/wild-flowers/ivy/

A milkweed on the shore: tracking down an elusive Danish plant

Since arriving in Odsherred towards the end of August I’ve been looking out for one plant in particular on our bicycle rides and hikes around the region. Vincetoxicum hirundinaria is a widespread asclepiad or milkweed: a member of the family Apocynaceae, subfamily Asclepiadoideae. This is a group of plants on which I’ve published quite a few research papers and which feature heavily in my book Pollinators & Pollination: Nature and Society.

So far the species has proven elusive and a few Danish ecologists that I’d spoken with told me they had never seen it in the wild. The GBIF account of the species shows a few populations in this part of Denmark but I wasn’t sure if they were old records of populations that no longer exist. But as of yesterday I can confirm that at least one of those populations is extant!

We had cycled out to the small town of Klint about 13km west of us, to see the glacial moraine landscape for which the area is famous and which gives Odsherred UNESCO Geopark status. As we approached the small fishing harbour at Klint I let out an excited shout to Karin who was just ahead of me: in amongst the roadside vegetation I’d spotted the distinctive and immediately recognisable yellow of Vincetoxicum hirundinaria in its autumnal hues! In the photos that follow you can see how well that yellow stands out against the colours of the other plants in the community.

At this time of the year the plant has ceased flowering, but the occasional swollen green seed pod was evidence of successful pollination of their morphologically complex flowers.

I was surprised at just how close to the sea the plants were growing; they must get inundated by sea water during stormy tidal surges.

So what is pollinating these flowers on this exposed shoreline? That’s a question that I want to pursue in the coming years. The Pollinators of Apocynaceae Database has remarkably few records of pollinators in this species, given how widespread it is. Flies certainly pollinate it, but there’s also records of wasps and bees as visitors, including bumblebees on flowers of a plant that I had in cultivation in Northampton. There’s a couple of other research groups in Scandinavia and Europe who are looking at the pollination ecology of the species and I’m hoping that we can collaborate on a study of spatial variation in its reproduction. Vincetoxicum is quite a large genus (around 150 species) and only around 10% of the species have been studied in any detail. But these studies are revealing a complex diversity of pollinators, including most recently, cockroaches in the Chinese species Vincetoxicum hainanense. I’m sure this intriguing group of plants has more fascinating stories to tell us about the ecology and evolution of its pollination systems.

FIGURE 4 from Xiong et al. (2020) Specialized cockroach pollination in the rare and
endangered plant Vincetoxicum hainanense in China. American Journal of Botany 107:
1355–1365.

If you read only two books this year make them The New Climate War and Silent Earth

My summer reading this year has included two books that I’ve really looked forward to, and which have not disappointed. These books are on the one hand very different and yet share enough similarities for me to review them together. Michael E. Mann’s The New Climate War focuses on the ‘climate emergency’ whilst Dave Goulson’s Silent Earth is about the ‘ecological emergency’, and specifically the decline of insect populations. As I pointed out in a recent New Scientist opinion piece: “the climate emergency often overshadows the ecological emergency, even though the two overlap both in their causes and their solutions”. Reading these two volumes in parallel has given me a much deeper understanding of just how true that statement is, and it’s why I’m suggesting that of the many, many books that have been recently written about our current environmental crisis, these deserve to be the ones that you read.

Silent Earth deals with the billions of small things – the insects and other invertebrates – that make the world function the way it does. These creatures facilitate the recycling of organic material, the pollination of wild and crop plants, the regulation of populations of other species, and play a host of additional ecological roles. The central thesis of the book is that the growing evidence of declines and extinctions of these small animals should give us cause for concern. In contrast, The New Climate War is about the big stuff – how the world’s atmosphere and oceans are heating up, the contribution of human activities to that warming, and what this means for weather patterns and sea levels across the globe. And how industry and politicians have conspired to deny, obfuscate, and divide, undermining efforts to decarbonise the world’s economy.

It matters not whether we view the world through a microscope or via an Earth observation satellite, both of these ways of seeing and understanding are important to our future as a species. The flap of a butterfly’s wings may only rarely be the indirect cause of a hurricane in the Caribbean, but reading these books nonetheless reminds us of the connections between the world’s biosphere and its physical domains.

The science underlying both books acts as a background to their main purpose: convincing the reader that there are urgent issues with which we, as a society, must deal. In this respect they are unapologetically political, and the point at which science meets environmentalism. The books are written by scientists who are respected experts in their respective fields, but who are not content with sitting back on their award- and citation-laden laurels, and allowing their science to speak for itself (as important as that is). Both Mann and Goulson have entered the more public arenas of politics and social commentary to argue the case for fundamental restructuring of some aspects of our societies. Their reward has been near constant criticism, much of it personal, vindictive and even threatening, by the vested interests of the fossil fuel industry (Mann) and agro-chemical & farming interests (Goulson) and the keyboard warriors who labour on their behalf, wittingly or not. That Mann and Goulson persist in voicing their concerns in this way, at the same time continuing to publish high quality science, says much about them as people and their commitment to these important causes.

The stereotype of the cold, calculating, emotionless scientist is shattered by these authors as they frequently refer to their families, especially their children, as a prime motivation for their activism. In an emotive chapter, Goulson imagines his son as an old man sitting up through the night to defend the vegetables that he’s growing with his family in a Britain that has experienced not an apocalyptic collapse of society and basic infrastructure, but “a slow unravelling over decades”. As he remembers back to the world of his youth he wonders: “Why did we fail to act? We humans do not seem to be very good at grasping the big picture”.

The Big Picture is certainly an underlying theme of both books, despite the different scales at which these scientists work, and both are revelatory in their descriptions of what’s occurring behind the scenes. Pull aside the curtain and we see the financial connections between various anti-environmental think tanks and lobby groups (Mann) and the hypocrisy of large business corporations which continue to manufacture highly toxic pesticides that, although banned in the west, can be profitably exported to developing countries (Goulson). All of these messages of corruption and environmental degradation could make the books pessimistic reads. But in fact both have an optimistic undertone, a sense that we know what the issues are, we know what’s got us into this mess, and there are routes out of it. But only if (and it is a huge if) there is the willingness of governments and large corporations to act.

Both writers share a belief in humour and personal anecdotes as vehicles for emphasising important points. For example Mann describing the fearsome and brutal attention given by climate deniers to Greta Thunberg and other youthful activists as being like the Eye of Sauron (one of several Lord of the Rings analogies). Or Goulson’s description of giving a phone interview to Australian radio while lurking in the piss-smelling toilet of a British pub. These books are brought to life by the authors’ experiences as scientists and as advocates, and their passionate wish for a better future.

Full disclosure: this can hardly be considered an objective review as both Dave Goulson and Mike Mann are friends of mine. Dave I met over thirty years ago when we were graduate students in the same department, and we’ve published a few things together. Mike I encountered much more recently, as I described in this post, when we were concurrently on sabbatical at the University of New South Wales and discovered that we were living in adjacent apartment blocks. In some respects the world of science is a very small one. Despite these personal connections I don’t think that I would have said much that’s different about either book had I not known their writers. But who knows, that’s not the way things are. There are certainly things to criticise in both books, and I don’t agree with all of the writers’ conclusions and could debate several points of interpretation with them, especially in Silent Earth where I’m in more comfortable territory. But those would be minor criticisms in light of the conclusions that these important books draw: that our world is changing rapidly, that we are responsible, and that we have a duty to act immediately. It’s not too late, but we need to listen to the science and what scientists such as Mann and Goulson are telling us.

A Copenhagen Bestiary – part 1

Since my first visit to Sweden in 1991 I’ve frequently traveled to Scandinavia for conferences, PhD defences, grant review panels, to catch up with friends, and to see my wife Karin‘s family in Denmark. So arriving in Copenhagen almost two weeks ago felt familiar and welcoming. There’s much that I love about Scandinavia, from the landscapes to the history and the peoples, but I am particularly enamoured by the city architecture of the early 19th to mid-20th centuries.

The old buildings of Copenhagen, where we are based for a few weeks, are at once familiar and yet alien, with respect to buildings of similar age in Britain. In particular, the unconstrained use of animals as ornamental adornments is fascinating, inventive and often bizarre. Some of these are real creatures, especially fish which represent the fishing industry on which the city was founded. Others are mythical beasts of traditional Scandinavian fables. And there’s a subset that are clearly the products of the (deranged? drugged?) minds of the sculptors.

Finland’s capital Helsinki tops the league when it comes to animals on buildings, but Copenhagen also has its fair share. I’ve taken to snapping these creatures as I encounter them so it seemed fitting to collect them into a bestiary – a compendium of beasts. Here’s the first set, presented with no commentary – the animals speak for themselves.

The largest West African flower: Pararistolochia goldieana!

Some years ago, browsing in a second hand bookshop, I happened across a copy of an old magazine from 1950 called Nigeria. Published by the then colonial government, it was a miscellaneous collection of articles about the culture, geography and natural history of that fascinating West African country. Although aspects of the contents are problematical by modern standards, I bought it because of a short article about a wild plant with enormous flowers and a remarkable pollination strategy. In particular, the spectacular photograph of a man holding a flower that’s the length of his forearm grabbed my attention: who couldn’t love a flower like that?!

The plant is Pararistolochia goldieana, a vine found in the forests of this region, as described in the introductory text:

These types of flowers are pollinated by flies, a common strategy in the Birthwort family (Aristolochiaceae) to which the plant belongs. This strategy of fly pollination in which flies are deceived into visiting the flowers by their stink and colour, and temporarily trapped in the enclosed chamber, is something that I explore in detail in my book Pollinators & Pollination: Nature and Society, particularly in the genus Ceropegia. Those plants show convergent evolution with the pollination systems of Aristolochiaceae, though they are unrelated.

Pararistolochia goldieana has a wide distribution across West Africa, including Cameroon, Equatorial Guinea, Nigeria, and Sierra Leone. The IUCN Red List categorises it as ‘Vulnerable’ due to habitat loss. The population where these photographs were taken is described on the final page of the article:

The city of Ibadan is one of the largest in Nigeria and has grown enormously, ‘from 40 km2 in the 1950s to 250 km2 in the 1990s‘. I wonder if this forest, and its botanical treasures, still exists?

During field work in Gabon in the 1990s I was fortunate enough to encounter a species of Pararistolochia in the rainforest of Lopé National Park. It was a different species to P. goldieana, with rather smaller but no less spectacular flowers, and it stank to high heaven! We knew it was there long before we saw it. I collected some flies from the flowers and had them identified, though I’ve never published the data: it’s available if anyone is working on a review of pollination in the family.

This 1950 article is anonymous, so I don’t know who to acknowledge for the amazing images. However the botanist R.W.J. Keay was working on a revision of the family for the Flora of West Tropical Africa project at the time, so it may have been written by him.

A spectacular new plant has been named to honour a colleague: meet Ceropegia heidukiae!

Finding organisms that have not previously been described by scientists is not unusual; every year, hundreds of ‘new’ species enter the taxonomic literature, a testament to how little we still understand about the Earth’s biodiversity. The majority of these species are insects, because that’s the most diverse group of organisms on the planet. But new species of plants and fungi also turn up regularly: for example in 2020, botanists and mycologists at Kew named 156, including some from Britain.

So although discovering undescribed species is not uncommon, any field biologist will tell you that it’s an exciting moment to spot something that you’re never seen before and which could turn out to be new. That was certainly the case when my colleague Dr Annemarie Heiduk’s attention was drawn to a South African plant that was clearly something special. As Anne said to me this week:

‘I will never ever forget the very moment when I spotted it and immediately knew it was something no-one has ever seen before. And I was so lucky to find it in flower. I cannot describe how beautiful it looked sticking out of the surrounding grass vegetation. It is certainly one of a kind and I really know how lucky I was to have found it. Not once did it ever cross my mind that I will discover a novel Ceropegia species, let alone one that is so distinct!’

So it was that last year Anne discovered the plant that was to be named in her honour: Ceropegia heidukiae. The species has been described by David Styles and Ulrich Meve in the journal Phytotaxa (from where the image above was taken). There’s also an account of the species on the Pollination Research Lab blog, with further photographs and information about the plant.

Anne has been honoured in this way not just because she discovered the plant, but also because, to quote the paper, she:

‘is a pollination ecologist who with her research on the floral chemistry and deceptive pollination strategies of Ceropegia trap flowers has acquired recognition as an expert in this field’

Anne tells me that she has already collected pollinator and floral scent data for this new species, so we can look forward to seeing that published in the near future. I described the fascinating pollination ecology of Ceropegia, including some of Anne’s earlier work, in my recent book. This is a genus of plants that has intrigued me since I first saw photographs of them and started growing them as a teenager, 40 years ago. Since then I’ve published several papers about their pollination strategies, and how they compare with the family Apocynaceae as a whole: see the following links for some examples:

https://jeffollerton.co.uk/2017/09/03/fly-pollination-in-the-trap-flower-genus-ceropegia-a-new-study-just-published/

https://jeffollerton.co.uk/2018/08/21/the-evolution-of-pollination-systems-in-one-of-the-largest-plant-families-a-new-study-just-published-download-it-for-free/

So, a big congratulations to Anne, and to David and Ulrich – it’s an amazing plant! I wonder what else is still waiting to be discovered in the stunning grasslands of South Africa?

New article just published: ‘Pollinators and pollination: myths, misunderstandings and much more to discover’

My first (and hopefully not my last) article for the magazine British Wildlife has just appeared in the April issue. Entitled ‘Pollinators and pollination: myths, misunderstandings and much more to discover’ you can get a preview here: https://www.britishwildlife.com/article/volume-32-number-5-page-316-323

The article focuses on some of the myths and misunderstandings that I dealt with in my book Pollinators & Pollination: Nature and Society. It also points out that, even in a place like Britain with a long tradition of natural history study, there’s still much for the patient observer to discover. If you’re interested in a PDF, drop me a line via the Contact page.

Pollinators are allies in the fight against climate change: a new commentary just published in New Scientist

Over the past few months I’ve been thinking a lot about the relationship between the “Climate Emergency” (CE) and the “Ecological Emergency” (EE), and how they overlap considerably in terms of causes and solutions, but that the priorities of the CE often trump those of the EE. One of the outcomes of this has been a commentary that’s been published in New Scientist this week. It’s free to access – here’s the link:

https://www.newscientist.com/article/mg24933260-100-pollinators-are-our-secret-weapon-in-the-fight-against-global-warming/

It’s extracted from a much longer article that discusses the role of pollinators in relation to climate change. Hopefully that will be published in the not too distant future.

The other thing that’s happened this week is that, in my role as Visiting Professor of Biodiversity at the University of Northampton, I was asked to take part in a webinar that’s one of a series being produced in support of the Levelling Up Goals. The LUGs, modelled on the UN’s Sustainable Development Goals (SDGs) have cross-party support in Parliament and aim to bring economic prosperity to those parts of the country that have lagged behind in recent decades. The “Green Economy” is seen as central to this.

The webinar was recorded and you can view it here: https://www.fit-for-purpose.org/engage/how-to-level-up-harness-the-energy-transition

It was interesting and I learned quite a bit, for example about how the government is investing the state pension pot in sustainable energy projects. The format of the webinar, however, with the chair asking individuals a question and each of us responding, was a little frustrating as there was no real opportunity to counter statements being made, particularly by the MP for Hexham.

Yesterday Karin and I had out first COVID-19 vaccination; today we both feel a little under the weather, but it will pass. It’s certainly better than the alternative!

Nature can’t solve all of our issues – sometimes we need therapy! Check out this new book: The Essential Companion to Talking Therapy

Talking Therapy Blue copy.jpg

About 20 years ago I went through a very difficult relationship break up. At the time I had a young family and found the whole thing too overwhelming to deal with. No amount of talking with friends and family helped. The current fashionable advice – “getting out into nature” – also did not help. Interacting with nature by walking, gardening or getting involved in active conservation, is a wonderful panacea for some mental health conditions. But it cannot solve all of our problems, especially those that come out of the blue. So I turned to therapy and had a series of weekly sessions with a therapist who provided a safe, neutral space for me to explore my emotions, anxieties about the future, and concerns for my own mental health. It was an amazingly useful experience.

Fast forward two decades and, lo and behold, I am married to a therapist! Not the same therapist I hasten to add, it’s purely coincidental!! Having a relationship with one of your clients would be hugely unethical on the therapist’s part, and ethical behaviour is just one of the themes that is in my wife’s new book.

So this is the reason for today’s blog post: it’s publication day for The Essential Companion to Talking Therapy by Karin Blak.

It’s the first volume of its kind that explains what you can expect to experience before, during and after therapy takes places. The book also deals with the many questions that you may have, or didn’t know to ask, about the therapeutic journey. It’s an invaluable read for anyone considering or going through therapy or counselling for issues around mental health, relationships, family problems, and so forth. It’s also got a useful section for families and friends on how to support a loved one who is in therapy.

Most importantly it provides a clear and rational argument for why therapy works, something that I only discovered for myself by going through the process. I wish I’d had this book 20 years ago.

The Essential Companion to Talking Therapy is available from all online booksellers around the globe, as a paperback or e-book. There’s also an audiobook version in the works.

OK, I’m clearly biased, but it is great book: well done darling, I’m so proud of you!

How old are the flowering plants? A new study aims to reconcile the fossil and DNA evidence – but what does it mean for pollinators?

Yesterday I was contacted by a journalist to give a comment on a paper that’s just been published in Nature Ecology and Evolution:

Silvestro, D., Bacon, C.D., Ding, W. et al. (2021) Fossil data support a pre-Cretaceous origin of flowering plants. Nature Ecology and Evolution https://doi.org/10.1038/s41559-020-01387-8

I was happy to do so as it adds a fascinating twist to a long-standing interest of mine: when did the angiosperms evolve and what role did pollinators play in that evolution?

In the end they didn’t use the text that I sent back to them, so I thought that I’d share it on the blog:

The evolution of the angiosperms was arguably one of the most significant events in the history of life on Earth, but the timing of the origin of this group of plants remains a hotly debated topic, with conflicting evidence coming from the fossil record and molecular biology. This important new study has developed a novel statistical approach to reconcile these two lines of evidence, and comes down firmly on the side of the molecular evidence to conclude that angiosperms originated much earlier than the fossil record suggests. This will be sure to stir up further debate that can only be resolved by finding well preserved and accurately interpreted fossils of an appropriate age. In the future I would like to see Silvestro et al.’s technique applied to the major groups of pollinators such as bees and wasps (Hymenoptera) and butterflies and moths (Lepidoptera) where there is likewise a discrepancy between what the fossils and DNA are telling us. Pollinators have had a profound influence on angiosperm evolution and we might expect a close correlation between the origin and subsequent diversification of these different groups of organisms. This would certainly support the findings from Silvestro et al.’s study. It’s an exciting time for researchers in this field: a world without flowers and pollinators would look very different