Category Archives: Biodiversity and culture

Watch my recent interview on Earth To Be

Recently I enjoyed chatting with Dr Daniela Scaccabarozzi for the YouTube channel that she runs called Earth To Be. In a wide ranging interview we discussed my recent book, how it came about, some of the things that intrigued me during its research (including a cockroach-pollinated flower!), and the role of people and pollinators in the wider ecosystem. Thanks to Daniela for the invitation to chat! Here’s the link to the interview.

Do bumblebees make honey? Yes and no…and…maybe [UPDATED]

As kids, my friends and I did a lot of digging. We always seemed to be burrowing into slopes or excavating trenches, pretending to be archaeologists or treasure hunters. Indeed, there was a lot of ground treasure to be found in the part of Sunderland where I grew up. The area has a long history of pottery and glass making, and ship building, and the remnants of these industries could be uncovered every time we stuck a spade in the earth. Over time I developed my own small museum of interesting, unearthed fragments, including bits of hand-painted ceramics, glass bottles, and unidentifiable metal shards, alongside various animal bones I’d excavated. My parents quietly indulged this interest, and my muck-streaked face and clothes, even if they didn’t quite understand what I was doing.

Aged about 10, my first encounter with a bumblebee nest was during one such dig. On the waste ground behind a large advertising hoarding, we began digging into a low, grass-covered mound and accidentally excavated what was probably a small nest of Buff-tailed Bumblebees (Bombus terrestris). I can recall being fascinated by the waxy, odd shaped cells and by the sticky fluid that some of them were leaking. Being an adventurous sort of child I tasted the liquid: it was sweet and sticky, and that was my first encounter with bumblebee “honey”.

I’m going to leave those quotation marks in place because if you do an online search for “do bumblebees make honey?” you generally find that the answer is “no, only honey bees make honey”.

Now, defining honey as something made by honey bee strikes me as a circular argument at best. And it also neglects the “honey” made by meliponine bees that is central to the culture of stingless bee keeping by indigenous groups in Central and South America, and the long tradition pre-colonial tradition of honey hunting by Aboriginal Australians. So if we widen our definition of “honey” as being the nectar*-derived fluid stored in the nests of social bees, then Apis honey bees, stingless bees and bumblebees must all, by logic, make honey. And likewise there’s wasps in the genus Brachygastra from Central and South America that are referred to as “honey wasps” because, well, I’m sure you can work it out!

But this is where things become a little trickier, because turning nectar* into honey involves some complex evaporation and enzymatic activity, so that the resulting fluid is more concentrated and dominated by the sugars glucose and fructose. Although analysis of honey bee honey is commonplace, and there’s been some research conducted on the honey of stingless bees, I don’t know of any studies that have compared Bombus honey with that of other bees, or with what is stored in the nests of honey wasps**. If I’ve missed anything, please do comment and let me know, but this strikes me as an area of research demanding some attention.

So do bumblebees make honey? That very much depends on our definitions, but I’m happy to accept that they do because “honey” is not a single thing: it’s an insect-derived substance that can take a range of forms but serves the same broad purpose of feeding the colony. And although insects have probably been producing it for millions of years, I think I’ve known the answer to the question for almost 50 of them…

UPDATE: A couple of people have commented on social media that there are legal definitions of “honey” as a foodstuff. Here’s the definition according to UK law***:

“the natural sweet substance produced by Apis mellifera bees from the nectar of plants or from secretions of living parts of plants or excretions of plant-sucking insects on the living parts of plants which the bees collect, transform by combining with specific substances of their own, deposit, dehydrate, store and leave in honeycombs to ripen and mature”

So, legally, we can’t call anything that isn’t made by Apis mellifera “honey”, at least from a foodstuffs regulation perspective. But that’s clearly different to what we have been discussing above, which is about a biological definition of honey.

It’s also interesting to look at the compositional requirements of honey as a foodstuff (presented in Schedule one of that document, if you follow the link above). The lower limit for moisture content is 20%. Now if you consider that most nectar in flowers has a sugar content of between about 20% and 50%, clearly there’s been a lot of evaporative work done by the bees to reduce the amount of water in the honey. I would love to know how bumblebee (and other insect) “honey” compares to this: do they put the same kind of effort into evaporating the water from the stored nectar? Given that the purpose of reducing the water content is to prevent fermentation by yeasts when it’s stored for a long time, and that there are bumblebee species which have colonies that are active for more than one year, I imagine that at least some species in some parts of their range may employ similar tactics.

Thanks to everyone who has been commenting and discussing the topic. It never ceases to amaze me how much we still do not understand about some fundamental aspects of the natural history of familiar species!

*And honeydew to a greater or lesser extent.

**I’m going to ignore honey pot ants for now as this is complex enough as it is and they don’t store the “honey” in nest cells.

***From what I can gather definitions in other countries are similar.

Solace in nature: sunset over Hov Vig bird reserve

The invasion of Ukraine by hostile Russian forces is a humanitarian disaster the likes of which Europe has not seen for decades, and hoped never to see again. Like many people, Karin and I have been watching the news about the war with a sense of helplessness, bewilderment and alarm, wondering how such things can come to pass in the 21st century. We thought we were past the stage where aggressive, narrow-minded dictators could bully their way into adjacent countries.

Faced with 24 hour media coverage of such desperate events, it’s easy to lose touch with the world around us. Karin and I are fortunate to be able to bicycle to some beautiful local spots where we can reflect and try to find some solace in nature. That’s what we did yesterday with a late afternoon visit to the Hov Vig bird reserve. In addition to my photos, which I’ll let speak for themselves, Karin filmed a short video for her YouTube channel which includes a marvelous array of bird calls.

Tonight we are taking part in a fund-raising event at the local culture house. Please think about how you can help to support Ukraine, in however modest a way, but also don’t forget to connect with nature. It will always endure, despite the destructive efforts of humans.

The value of nature, the value of guitars

How we, as a society, value nature, and the tension between valuing (or appreciating) nature versus appreciating (or pouring money into) human cultural activities, have been consistent themes of this blog since I started it almost a decade ago; see for example my posts “How do we value nature? Costanza, Monbiot and the clash of concepts” and “Is the angry response of (some) environmentalists in the aftermath of the Notre Dame fire reasonable?

Putting a monetary price on nature runs counter to the personal philosophies of many conservationists, which I completely understand: I have mixed feelings too. However there’s a whole field of research devoted to it called Ecological Economics and the valuation of natural capital and ecosystem services now plays a central role in the policies and strategies of both businesses and governments: see for instance the UK Government’s recent report on “The Economics of Biodiversity: The Dasgupta Review“. And whether we like it or not, the Earth’s ecosystems and the biodiversity that they contain support our global economy in very tangible ways, a point that I emphasise in my book Pollinators & Pollination: Nature and Society. If you’re reading this with a cup of coffee in your hand, you have to consider the ecological and financial impact of the billions of wild and managed bees that support the global coffee industry.

“What’s all of this got to do with guitars?” I hear you asking. Well, music, and especially guitars, are another constant theme of the blog, including my love of the songs of Crosby, Stills, Nash and Young, and my restoration of an old acoustic guitar back in 2020.

These themes converged together in a rather unexpected way just over a week ago. It was my birthday and as a present Karin had offered to buy me a new guitar. So off we went to Copenhagen for the day. One of the city’s best guitar shops is Akustikken and there I tried out several makes and models of acoustic guitar, of varying price and quality, before finally settling on an Epiphone Texan in an aged sunburst finish (see the image below). It plays very nicely, felt right in my hands, and was moderately priced despite its solid wood construction (cheap guitars often use laminated wood).

The guitar that really caught my eye, however, was the one in the photograph above: a Martin 045-S Stephen Stills Signature Model. Now, this is a serious, serious guitar. Based on a 1930s model owned by Stills himself, it was hand made in the USA in a limited edition of 91, of which this was number 48. The woods from which it’s made are rare and exceptional, including Adirondack spruce, Madagascar rosewood, and ebony, all species about which there are significant conservation concerns (see Richard Hobbs’s great blog The Nature of Music for more on this – highly recommended for anyone interested in the interface between human culture and ecological conservation).

The price tag for this guitar? A mere160,000 Danish kroner, about £18,000 or $20,000…..

That was WAY outside of our budget! But when the staff learned that it was my birthday they kindly took the Martin out of its humidity-controlled glass case and let me play it. I was a bit overwhelmed and very nervous if I’m honest, it was easily the most expensive guitar I have ever had in my hands! Karin took a short video of me strumming a few chords which I uploaded to Twitter:

Now, I’d played guitars up to around $2,000 in price that day, so a reasonable question is: did the $20,000 guitar sound ten times as good? Well, not in my hands it didn’t…. But in one sense it doesn’t matter, you’re not just paying for what it sounds like, you’re paying for the story, for the association with Stills, and the highly skilled crafting of the guitar – it is an exceptionally beautiful and fine-sounding instrument.

This brings us back to nature. We know from a lot of ecological experiments that have been conducted over the years that there’s a positive relationship between biodiversity (measured by the number of species in an ecosystem) and the way in which that ecosystem functions. So if you have more different kinds of plants in a grassland, for example, there tends to be greater carbon capture, more efficient use of water and uptake of nitrates from the soil, more resilience to events like drought and fire, and so forth. This is a strong and pervasive argument for conserving species within ecosystems: the more we have, the better the “health” of that ecosystem.

But, as with the sound of guitars, there’s probably an upper limit to this and ecosystems with ten times as many species probably do not function ten times as well. But they do function better. Having said that, this is a complex area of research with some competing ideas (and scientists) – this Wiki provides quite a good summary.

Regardless of the technical details, there’s no doubt that having more pollinators in an ecosystem, for example, increases the reproduction of a wider range of the plants that are present. Or that the presence of a greater diversity of dung beetles improves the rate of dung removal in grasslands.

But of course nature is more complicated than this. Just as a well made and high-value guitar is never going to sound good in the hands of a poor guitarist, likewise, species diversity in itself is insufficient. It is the interactions between those species that determines much of the way in which the ecosystem functions, and an ecosystem is never going to function well over the long term if it is inappropriately managed or if the processes that shape ecosystems, such as grazing by wild herbivores or natural fire regimes, are absent or have been altered.

Ecology is a hugely complex science but perhaps by exploring metaphors like this, some of that complexity can be made accessible to a wider range of people. Tell me what you think, does the metaphor work for you?

Why are there camels carved on this late medieval tomb?

In past posts I’ve written about my fascination with grave markers and the depictions of animals and plants that are sometimes featured, or their dual use as both tombstone and bird bath. It’s part of my broader interest in the relationship between humans and the rest of nature, and specifically biodiversity and culture. I’m intrigued by what taxa we choose to use as decoration and symbolism, and conversely those species that are rarely or never a part of the human cultural expression of life on Earth. Graveyards and churches are prime hunting grounds for this sort of enquiry, and I find it difficult to walk past an old cemetery without at least a quick visit.

During our recent Christmas family gathering in Glastonbury Karin and I briefly dropped into St John’s Church and I spotted an intriguing late medieval tomb decorated with what are clearly Bactrian camels.

I have not previously seen camels depicted on a tomb – even the grave of the famed desert explorer Sir Richard Francis Burton can only manage a Bedouin tent. Also, the date of the tomb – 1487 – seemed very early for such an exotic depiction. So I did a little sleuthing on the topic of camels in medieval Britain and came across Dr Caitlin Green’s blog post asking “Were there camels in medieval Britain?“. The answer is yes, and as Dr Green’s research has shown, they were often depicted in illuminated manuscripts, tapestries, stained glass and other media, at dates even earlier than the late 15th century.

But why are there camels on this particular tomb? The memorial belongs to John Camel and I suspect that the carvings are simply a play on his name – a sculptural pun. John is described as a lay treasurer for Glastonbury Abbey and may also have been involved in legal work, all of which sounds very dry and prosaic. But if it was John himself who commissioned this tomb, or his family that wanted a memorial which reflected his personality, it suggests to me that he certainly had a sense of humour.

“Camel” is a common place-name element in the south west of England: there’s both a river and a hill with that name, and of course King Arthur’s Camelot is reputed to be located here. The etymology of camel in this geographical sense is varied and sometimes obscure, but one thing is certain: it’s nothing to do with the even-toed ungulate mammals of the genus Camelus.

As I was writing this post it occurred to me that Burton’s Sufi-inspired poem The Kasîdah of Hâjî Abdû El-Yezdî includes some fitting lines on which to end:

“All other Life is living Death, a world where none but Phantoms dwell,
A breath, a wind, a sound, a voice, a tinkling of the camel-bell”

Generating AI art from titles of scientific publications

WARNING: huge time wasting potential ahead.

As regulars to my blog might know, I’m a sucker for computer-generated “stuff”, for example virtual ecological systems; see my 2020 post “a simple online ecosystem model: like Tamagotchi for the green generation“. Last night while browsing Twitter I came across a few people tweeting about which uses words and phrases as a prompt for its AI to generate art in a variety of styles. For example, the image above is based on the title of my book Pollinators & Pollination: Nature and Society. The downloaded image always has “dream” at the top which is easy enough to crop, while “PROMPT” is the word or phrase that you entered, which can be turned off.

You can also use the titles of scientific articles – this one is my 1996 paper “Generalization in Pollination systems and Why it Matters” (I don’t think that it counts as a graphical abstract…):

A lot of people were submitting their thesis titles and I expect to see some of these used as frontispieces in PhDs in the near future. Here’s mine (from 1993) – “Ecology of flowering and fruiting in Lotus corniculatus“:

The other category that I had fun with was using scientific names – here’s the genus Ceropegia:

And here is Apocynaceae:

Can you guess what phrase I used to generate this one:

What’s really fascinating about this system is that every time you generate an image from the same phrase it returns something different. Go have fun, but be warned: it’s a bit of a rabbit hole and it’s possible to waste a lot of time playing around:

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:

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.

Bumblebee Conservation Trust (2021) Ivy mining bee:

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.

A Copenhagen (and beyond) Bestiary – part 5

At the end of August I was back in Copenhagen for a couple of days to take part in the PhD defence of Céline Moreaux, who has been working on coffee pollination and bee conservation. While I was there I snapped a couple more images for my Copenhagen Bestiary series. However I’ve also seen some interesting sculpture and building decoration further afield this month, in Aarhus, Silkeborg, and Nykøbing Sjælland. I especially like the wooden carved canopy support in the form of a duck, from Aarhus: it’s very subtle and I almost walked past it.

And before anyone asks, no, Karin and I are NOT part of the bestiary, but I didn’t get a shot of the troll by itself.

Wild mushrooms, tragic deaths, and the importance of understanding nature

A sad and timely news story caught our eye this morning: the death of two young Afghan boys in Poland who were poisoned after their family collected wild mushrooms to make a soup. Other members of the family were hospitalised. As Karin read out the story to me, I was moved by the tragedy of these events for a family fleeing a war zone, but also angered by pointlessness of the loss of those brothers’ lives, just more death-by-wild-mushroom statistics. In Europe we read about such events every year in the autumn, the peak of wild fungus foraging. And quite often the deaths are of people who have recently moved to an area and mistake poisonous mushrooms for edible ones from their country of origin.

At their root, these tragic stories of lost lives and broken families are stories of misunderstandings about nature. In particular, they are about not appreciating that plants, mushrooms, animals, and other wildlife, are not the same all over the world. There are biogeographic differences between regions that reflect the long-term history of life on our planet. Plants or mushrooms that look superficially similar in different parts of the world may have very different evolutionary histories. Histories that can make the difference between good to eat and deadly poisonous, between life and death.

The mushroom which killed the boys was a Death Cap (Amanita phalloides) which is found across Europe and the Mediterranean basin. As far as I can tell from its GBIF records, it does not occur in Afghanistan. The family presumably mistook this mushroom for one with which they were familiar, perhaps a different species of Amanita, which contains both deadly types and some that are good to eat. This terrible and fatal mix up could so easily have been avoided.

I’m not certain if resettlement agencies provide information about the foraging of wild food, or if basic facts about local nature are provided to those new to these areas. This is a simple action that could save lives and further tragedies for families trying to recover after the disruption of moving to a new country. It may be that this family was trying to carry on traditions of foraging in an effort to feel at home.

Since we arrived in the Odsherred region of Denmark, where Karin and I intend to settle, we have been exploring the woods and beaches on our newly bought bicycles. Much of the natural history is familiar to me from Britain, but there’s also some interesting differences and in future blog posts I’ll discuss this further. Last week we happened across a Lithuanian woman and her mother who had been foraging for mushrooms in the forest around their summer house. They were pushing a baby’s pram, the lower basket of which was stuffed with fungi. Picking and eating wild mushrooms has been something I’ve enjoyed since I was a teenager, so I had to stop and chat with them. They showed us some of their finds, including species with which I wasn’t familiar and that I will research further.

Lithuania and Denmark are of course quite close to each other geographically. Nonetheless the younger woman was still discovering which of the local mushrooms were good to eat: ‘I learn one new edible species each year’ she told us ‘That’s a good rule, then you don’t get confused’.

Since that meeting we’ve had several meals from mushrooms collected in the area, including some very fine ceps (Boletus edulus). I will keep in mind the woman’s words and proceed cautiously when it comes to discovering what is edible and what is not.

To end this rather sad but hopefully thought provoking post, Karin and I send our deepest condolences to the Afghan family and our heartfelt wishes that they can recover from these tragedies that must have deeply affected their lives.

A Copenhagen Bestiary – part 4

We have now left Copenhagen, taking a (very comfortable) train over to Silkeborg to catch up with Karin‘s family for a week. So this is the final installment of the Copenhagen Bestiary for now, but I’m sure that I will add to it as I return to the city and explore further. I suspect that there are many more creatures to discover adorning the architecture of that wonderful city. And then there’s Aarhus, Odense, Roskilde….