Author Archives: Markus Eichhorn

About Markus Eichhorn

I'm a lecturer in ecology at University College Cork. My research studies how patterns of trees in forests form, and how the organisation of forests influences the things that live inside them. Hence trees in space!

Decolonise biogeography!


Arthur Sinclair in Peru. This image is taken from a fundraising page set up by his great-grandson, the writer Iain Sinclair, who is currently writing a book and producing a podcast series based on his attempts to retrace the original expedition.

Arthur Sinclair was a Scottish explorer and geographer whose most influential commission was his 1890 survey of half a million square miles of interior Peru produced on behalf of the Peruvian Corporation of London. In his report* he expresses limited sympathy for the indigenous inhabitants of this vast wilderness:

Poor Chuncho! The time seems to be approaching when, in vulgar parlance, you must take a back seat; but it must be acknowledged you have had a long lease of those magnificent lands, and done very little with them… The world, indeed, has been made neither better nor richer by your existence, and now the space you occupy — or rather wander in — to so little purpose, is required, and the wealth of vegetation too long allowed to run waste, must be turned to some useful account.

Modern readers with our current sensibilities will gasp at the patronising imperialism embedded in these words. Anyone with an awareness of the subsequent consequences for the people who once lived in and depended on these forests, not to mention the damage to the forests themselves, will be appalled that devastating change was proposed with such casual insouciance.

Attitudes of this nature were widespread among the imperial powers. I don’t mean to pick on Sinclair as a particularly egregious example because he wasn’t. My choice of this passage is solely due to the coincidence of having come across it recently, but I could have chosen from many; some now notorious, others obscure but nonetheless consequential at the time they were written. For example, Sinclair’s explorations took place at the same time as Joseph Conrad was embarking on his own travels into the Congo basin**.


The Peruvian railway system was a triumph of colonial engineering which opened the interior of the country for trade and resource extraction. Photo by David Gubler. Source: Wikimedia Commons.

For all we might be appalled by the opinions of our predecessors, and strongly disavow them now, as biogeographers we must face up to the fact that our field arose first and foremost as an exercise in colonialism. Its raisin d’etre was to describe, delineate and evaluate the natural wealth of foreign lands for the benefit of colonial powers. We remain complicit while our institutions continue to memorialise and celebrate our forebears, often in buildings paid for by the proceeds of slavery, extraction of resources and appropriation of land. It’s not sufficient to say that we know better now when the advantages we accumulated through colonialism reinforce persistent inequalities.

In our new paper*** we draw attention to this ongoing problem. Ironically human geographers are acutely aware of the need to engage with colonial legacies, while the physical and biogeographers with whom they often share buildings typically assume that such concerns do not apply to them. This position cannot be defended.

One way in which this applies is in the distribution of biogeographical researchers. We extracted the institutional addresses of over 7000 authors of papers in the three leading journals of biogeography over a five year period, and show that only 11% of them are based in the tropics. Over 5000 of them are in the northern hemisphere, mostly in what we consider Global North countries.


Distribution of all authors contributing to papers in the three main international journals of biogeography over a five year period (2014–2018). Figure 1 in Eichhorn et al. (2020).

There are lots of forces underlying this pattern, but they all act to reinforce the dominance of Global North institutions. I don’t doubt that it would be similar for many other academic fields; this however only demonstrates how pervasive the problem is.

Meanwhile, the predominant flow of information (as data and records) is from Global South countries towards these centres of influence. The main databases which compile global biogeographical records are based in Europe, North America or Australia, and are maintained by researchers based in those countries. Is this harvesting of data any different in its dynamics to that of colonial resources?

Another issue is that, mostly subconsciously, the way that studies from Global North countries are described and framed differs from those published elsewhere. In a brilliant study published last year, Ergin & Alkan parse the signal of academic neo-colonialism in the language used by authors. Global North scholars write from a perspective of supposedly impartial generality, while southern scholars include geographical indicators that reinforce their position as producing localised case studies or applications.

This is an insidious effect, and easily deniable until pointed out. When one of the reviewers questioned this, it took me only a few moments to identify a number of papers from Wytham Woods (a study site in Oxfordshire) with titles that gave no hint of their origins, and purport to make broad ecological statements. Would a paper from the Rwenzoris in Rwanda be written, accepted and published with the same level of detached abstraction? I severely doubt it.

What can we do? On recognising the problem our collective responsibility is to reverse the trend. This depends on the behaviours of individuals and research groups. Capacity building, proper recognition of collaborators and support for research agendas from beyond the Global North are all part of the process. Opening up biogeography also means enabling researchers from across the world to not only have access to repositories of data, but to develop and host their own. And when we write, we should learn from the humanities and recognise how our positionality inflects the way we view and describe the world around us.

Achieving these things is not merely an act of contrition for past injustices; opening up the field will increase the diversity of insights and validity of our findings, making  biogeography into a truly global science. We need to decolonise biogeography.


* I obtained this excerpt from the travel diary of his ancestor Iain Sinclair, who is no apologist for his great-grandfather. He also has a blog serialising his attempts to retrace the path of the Peru expedition.

** Please don’t send me comments along the lines of how Heart of Darkness is a classic of world literature. It is both a classic work and appallingly racist.

*** Thanks to my brilliant coauthors Kate Baker and Mark Griffiths who continue to teach, inspire and provoke me with their insights.


Books I haven’t read

V.D10 Origin 1st edn title page_0

The opening pages of Darwin’s classic text in its first edition as held by the library of St John’s College, Cambridge.

A number of years ago on a UK radio show there was a flurry of attention when Richard Dawkins, under pressure from a religious interviewer, was unable to recall the full title of Darwin’s most famous book*. This was perceived as a flaw in his authority as an evolutionary biologist. How could he claim to support evolution if he couldn’t even name the book which launched the theory?

There was a prompt backlash to this line of argument from scientists who pointed out that we don’t have sacred texts in science. Unlike religions which fixate upon a single original source**, we recognise those who made contributions to the development of our field but don’t treat them as inviolable truth. Darwin, like all scientists, got some things wrong, didn’t quite manage to figure out some other problems, and occasionally changed his mind. None of this undermines his brilliance; the overwhelming majority of his ideas have stood the test of time, and given the resources and knowledge he had available to him (remembering that it was another century until we understood the structure of DNA), his achievement was astonishing.

Confession time: I haven’t read On the Origin. Maybe I will one day, but right now it’s not on my very long reading list.

There are many good reasons for reading On the Origin, none of which I need to be told. By all accounts it’s a fascinating, well-written and detailed argument from first principles for the centrality of natural selection in evolution. As a historical document and inspiration for the entire field of biology its importance is unquestionable. I’m certain that Richard Dawkins has read it, even if he didn’t memorise the title.

None of this means that I have to read it. The fundamental insight has been affirmed, repeated and strengthened by over 150 years of scientific study and publication. Even though I used to be a creationist, it didn’t take reading Darwin to change my mind***. What we know now makes a modern account more convincing than a Victorian naturalist could ever have managed.

An even more embarrassing confession is that I haven’t read The Theory of Island Biogeography****. This admission is likely to provoke horror in anyone from that generation of ecologists (my own lecturers) who remember the seismic impact that MacArthur & Wilson’s 1967 book had on the field. It defined the direction of enquiry in many areas of ecology for decades afterwards and effectively founded the scientific discipline of conservation biology. Some of their ideas turned out to be flawed, but the majority of ecologists still view the central model as effectively proven.

I’m not one of them. Yes, I apparently fall among the minority of ecologists, albeit led by some pretty influential voices, who view the model as so partial and incomplete as to lack predictive value in the real world (I’m not going to lay out my argument here, I’ve done that before). That I’ve reached this decision without reading the original book doesn’t perturb me in the slightest. In the same way as I’m confident that I can understand evolutionary theory without reading Darwin, I’ve read enough accounts of the Equilibrium Model of Island Biogeography (and taught it to undergraduates) that it’s not as if going back to the original source will change my mind.

If this upsets you then consider whether you’re happy to agree with the majority of evolutionary biologists that Lamarck’s model of inheritance was wrong without without bothering to read Lamarck (or his later advocate Lysenko). Lamarck made many great contributions to science; this wasn’t among them. For similar reasons I’m happy to make judgements on Haeckel’s embryological model of evolution (rejected), Wegener’s theory of plate tectonics (accepted), or Hubbell’s neutral theory (ambivalent), all without reading the original books.

What have I actually read then? Among the great classics of our field I’m pleased to have gone through a large number of Wallace’s original works, which were contemporaneous to Darwin, and Humboldt’s Essay on the Geography of Plants (1807). I can strongly recommend them. But they didn’t change my mind about anything. It was enjoyable to go back to the original sources, and by the end I was even more impressed by the authors’ achievements than before, but my understanding of the world remained unaltered. For that reason I wouldn’t ever claim that everyone should read them.

There are, however, a number of books which have changed my mind or radically reorganised my understanding of the world. These include Chase & Leibold’s 2003 book about niches or Whittaker & Fernandez-Palacios on islands. Without having read them I wouldn’t hold the opinions that I do today. I’m glad that I placed those higher on my reading list than On the Origin. But that certainly doesn’t make them essential reading for everyone.

We all follow our own intellectual journeys through science and there is no one true path. For this reason I’m always sceptical of attempts to set essential reading lists, such as the 100 papers every ecologist needs to read, which I and others disagreed with more on principle than content. So yes, if you like, you can think less of me for the reading that I haven’t done. But my guess is that many people who read this post will be feeling a quiet reassurance that it’s not just them, and that it’s nothing to be ashamed about.


* It is, of course, the barely memorable “On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life.”

** This in itself is baffling given that sacred texts have their own complex histories of assembly from multiple sources. Most modern Christians don’t dwell on the fact that the issue of which books to include in the Bible was so contentious, especially for the Old Testament, and some traditions persist with quite different Bibles. Why include Daniel but not Enoch? Then there’s deciding which version should be seen as definitive, and whose translation… it’s not as simple as picking the one true book.

*** Notably a dominant theme in creationist critiques of evolution is to pick away at perceived errors or inconsistencies in Darwin’s writings on the assumption that undermining its originator will unravel the whole enterprise of modern biology.

**** And this from a former book reviews editor of the journal Frontiers of Biogeography. They’ll be throwing me out of the Irritable Biogeography Society next.


Class exercises for teaching conservation biology

I’m in the midst of writing a new module in Conservation Biology. It’s quite exciting (and daunting) to start a course with an entirely blank slate. Finding material for the lectures is no problem because I’m following a standard textbook and there’s never a shortage of examples in the literature. It’s always more difficult to come up with class exercises though. These are crucial to engage students with the subject matter and get them to critically evaluate different positions, including their own.

This is the first time I’ve taught a whole module on the subject, but luckily there are many others who have trodden the same path before me, so I put out a call for ideas on Twitter:

As expected, this provoked an avalanche of brilliant ideas, all classroom-tested and ready to roll out. Rather than hoard them all, here’s a summary of the suggestions, several of which I’m already planning to deploy.

Unsurprisingly there are already resources out there, so before developing something on your own take a look at the online collections provided by @sesync, @CaseStudEnv, @BIOINTERACTIVE, @CBC_AMNH, National Center for Case Study Teaching in Science, CISV International (including one on deforestation in DR Congo), HNV Link on agroecosystems, as well as the discussion questions in many textbooks. Below are just the ones that were suggested directly.

A great idea which I had already stolen from @juliapgjones is to launch into the course by getting the students to take the Future of Conservation survey:

This is a great way to get students to explore their own attitudes and preconceptions at the outset, which provides a foundation for them to reflect on the material and their responses to it. There’s even a GO-FOX tool which allows you to carry out bespoke surveys for closed groups, allowing students to compare their opinions to the rest of the class. Even if you’re an experienced conservation practitioner I recommend you to do the test; it’s very revealing.

One of the oldest arguments in conservation biology is the SLOSS debate over reserve design (Single Large Or Several Small). I admit to being a little weary of this one based on the simple observation that such abstract, idealised concepts almost never play out in reality. Nevertheless, as an exercise in discussing where our priorities should lie, this is a nice self-contained topic to work on. For example, students could be given a hypothetical landscape and invited to discuss how to distribute a limited reserve area within it. @LauraEllenDee has a jigsaw exercise based on her recent paper which covers this material nicely.

A related issue, and perhaps closer to what happens on the ground, is to look at the tension between land sharing and sparing:

Biodiversity trade-offs are another great opportunity to turn into a game. Having known @jlsnaddon for some time, it doesn’t surprise me that he’s found a way to transform this simple idea into something that looks professionally designed:

Another fun game comes from this set of notes for a class on the Tragedy of the Commons, which @CarlaWildlife has adapted using Skittles. She also has more suggestions:

One way to take conservation strategy away from abstract considerations is to use real-world case studies. Students can be invited to choose sites worldwide, download species lists, calculate EDGE scores or other biodiversity metrics, and identify possible actions or priorities in either a poster or talk. It sounds as though there’s an interesting publication coming up which does exactly this:

A number of people recommended roleplay exercises as a great way to explore the different sides of complex debates in conservation. Students often get so involved in the discussion that this becomes quite heated. Not unlike the real world. A great one to whet the appetite is the issue of feral cats, with some good evidence of impacts on piping plovers. The harvesting of sea turtle eggs is another. You could raise the stakes by turning it into a shark tank dynamic (which I think is the same as a balloon debate). You can even get a good argument out of students by looking out of the window and asking about the differences in conservation value between a lawn and an unmanaged patch.

Another topic with a well-established body of conservation theory is Population Viability Analysis, and here again students can try out the calculations for themselves (I imagine this is often quite sobering):

Debates are also an important tool. For example:

This sounds like a great question. I’m wary of setting quite so much compulsory reading, although Feral and Rambunctious Garden sound very provocative and I should probably read them myself.

Other common tools are online quizzes followed by class discussion (Mentimeter is a recommended tool), showing or making students create videos, or getting them to develop their own case studies which they can present back to the class:

Finally, I’m intrigued by a suggestion from @Tarsiussallius of bringing in some Citizen Science element; I’ll have to think more about how to achieve that (and would love to hear from anyone who has done this).

This post is a work in progress and I’d welcome any other suggestions or feedback based on class experience. If you have a great exercise (or know of one) then why not nominate it for the Case Studies in the Environment Prize? Fame, glory and $2000 could be yours.


Thanks for input on this post (in order of their replies in the original thread) to @ecoevoenviro, @Jungle_Lou, @bonebraking, @Honor_Prentice, @juliapgjones, @bangorherps, @EntoProf, @SaraScanga, @LauraEllenDee, @jlsnaddon, @ja_tobias, @LaMontagneLab, @Zen_of_Science, @mceuen_amy, @Tarsiussallius, @KampJohannes, @OrnithoAle, @TraciInFinland, @_GeorgeHolmes, @josephjbailey, @Dr_Stoat, @KStackWhitney, @CaseStudEnv, @katiemattaini, @megcevans, @CarlaWildlife, @katzyna, @Rosie_Baillie_, @Xim_Neri, @yitarn. If you’re looking for an inspiring set of conservation educators on Twitter then follow all of them.



How much leaf area does a tree have?


The Bird Tree (it’s actually a cork oak, Quercus suber), Haute-Corse, France. Nominated as European Tree of the Year in 2019 but came in a disappointing 4th place.

What is the total area of leaves on a tree? On the one hand, this is a pretty obvious question to ask. Leaves are the exchange surfaces of plants, absorbing light, taking in carbon dioxide and releasing oxygen and water vapour. If we want to measure the rates at which each of these occurs for an individual tree then the area of their leaves is an essential parameter.

On the other hand, the total leaf area of a tree is an extremely difficult thing to measure, which is why for the most part we don’t bother. Up until now the only way to do so would be to pull all the leaves off a tree, measure them individually, then add the areas together. This kind of destructive sampling is generally frowned upon and makes long-term monitoring impossible.

Forest ecologists have therefore developed a range of alternative metrics which capture something of the same information. The most commonly used is Leaf Area Index (LAI), which gives the average number of leaf layers in a forest stand (strictly speaking it’s an estimate of the leaf area per unit ground area). This is very useful for modelling forests at the ecosystem level, where the overall area available for transpiration or gas exchange is important. But if you’re interested in the growth of individual trees, as I am, then it’s not much help. Likewise if you care about the foliage available as either habitat or food for herbivores, or where in the canopy those leaves actually are, LAI doesn’t provide the resolution you really need.

Terrestrial laser scanning has often been touted as a grand solution to challenges such as this. A conventional scanning laser can in theory measure at 2 mm resolution up to 50 metres away, which sounds impressive. Certainly the point clouds provide stunning visualisations which always make an impact in a presentation*.


A 10 x 50 m reconstruction of a UK woodland as used in our paper on deer browsing impacts, surveyed by Joe Ryding.

There are a number of challenges though, and some of the over-ambitious expectations for laser-scanning derive from a few misconceptions. Dealing with these is an essential first step.

The main thing to clarify is that laser scanners don’t directly measure the amount of stuff; they measure the distance to stuff. A point cloud shows the nearest thing to the laser scanner that a beam actually struck**. That beam (you might want to think of it as a vector) is a straight line from the scanner which stops when it hits something, and everything past that point is effectively invisible. We refer to this as the occlusion problem, and it causes all sorts of issues.

To use a logical argument made famous by Donald Rumsfeld, what lies behind the first point in a laser beam’s pathway are a lot of known unknowns. We know there’s nothing until the first point (known absences), until it hits an object (a known known). After that we have no information. On top of this, coverage of laser beams is never continuous, and they spread out with distance from the scanner, so even at the highest resolution there are many things that the laser beams wouldn’t ever strike anyway.


A conventional scanning laser in action in the forest. The white globe in the background acts as a reference point for linking multiple scans together. What we see in our visualisations is only what the scanner can see. Photo credit Joe Ryding.

To cut a long story short, terrestrial laser scanning provides a biased sample of the amount of stuff in a habitat, not a complete picture, however seductive our visualisations appear. We know it’s biased but we don’t know how much we’re missing. If we want to use our point cloud to estimate leaf area then we need to fill in the gaps.

In our new paper we provide a proof-of-concept for doing exactly this based on a computer simulation approach. The first step was to take a set of trees for which we knew the sizes, positions and angles of every single leaf (this was a mammoth sampling effort for which credit goes to my collaborator Sylvain Pincebourde and his team). Then we reconstructed those trees using computer graphics and simulated terrestrial laser scanning in a similar fashion to what would take place in the field. The next phase, which was also relatively novel, was to develop an algorithm to convert point clouds into flat surfaces. We could then use the area of these to create a direct estimate of tree leaf area.

Why do this? Well, it allows us to quantify exactly what proportion of the true leaf area we are theoretically able to replicate, identify how much we might be missing, and work out how our coverage varies through the canopy. It varies between the five trees, unsurprisingly, but the main lesson comes from what it tells us about the effectiveness of terrestrial laser scanning overall.


Graphical abstract from our paper. This illustrates the process of virtual scanning, conversion of points to surfaces, and comparison of different scanning approaches.

Scanning a single tree from one viewing point on the ground allows us to reconstruct only around 30% of the leaf canopy. That’s not particularly great. However, with three scanning positions around the tree, we could raise coverage to around 67% of leaf area (this scanning method matches standard recommendations). Two-thirds of leaf area might not sound amazing, but it’s better than anyone else has managed, and still much easier than pulling all the leaves off! Finally, adding an airborne scan pushes the recovery rate higher still, up to a maximum of 90%, but there are practical issues that mean this is unlikely to work with current technology, at least unless the LiDAR device is mounted on something solid like a canopy crane. All these are also theoretical maximum values; in the real world problems such as moving leaves or additional obstructions will reduce coverage.

The good news, however, is that it’s possible to get a direct estimate of tree leaf area with a laser scanner, and we have a starting point to work from. As with any new technology we’re still at the outset. Lots of people have been working on using terrestrial laser scanning to measure timber volume or tree heights but leaf area remains challenging. The next step is to see how this might integrate with hand-held mobile scanning lasers. What we have provided is a platform that at last allows us to evaluate the known unknowns and find a way to compensate for them. Eventually that means we should be able to answer the original question — what’s the area of leaves on a tree — without needing to remove a single leaf.


Yun T., Cao L., An F., Chen B., Xue L., Li W., Pincebourde S., Smith M.J.  and Eichhorn M.P. (2019). Simulation of multi-platform LiDAR for assessing total leaf area in tree crowns. Agricultural and Forest Meteorology, 266–277, 107610. pdf


* And would make a stunning addition to this blog post if I had paid for a full WordPress account which allowed me to include videos. But I haven’t. So look here instead.

** For simplicity let’s not talk about split beams or multiple-return LiDAR. That gets messy very quickly.

Did I actually lose my faith?


Abandoned church in Italy. Photography by Roman Robroek from a series on abandoned houses of worship in Europe. Used with permission.

It’s now more than twenty years since I left Christianity and became an atheist. There was no Damascene conversion; like many people I drifted away rather than having a sudden insight. A series of events and discoveries led me to finally break from the church, although it took moving country to finally sever the social bonds and expectations that had kept me involved long after I would otherwise have left.

It’s been a long psychological journey from growing up as a creationist in a church of Biblical literalists (not the extreme Young Earth kind, but close enough) to becoming a professional academic biologist who teaches evolution. In that time I’ve established a career, worked all over the world, started a family, lost some friends and gained many more. All the turbulence that makes up a fairly normal life. Neither the good times nor the bad have led me to reconsider my position on religion.

The last two decades were also a period during which the tension between science and religion broke into mainstream discourse. A number of prominent atheists derided what they saw as unreason; none of the arguments were new but their vehemence and prominence were unusual. Of the main figures, the most persuasive was Christopher Hitchens, a man by all accounts possessed of magnetic charisma, compelling in debate and uncompromising in his writings. Other notable contributions were Dawkins’ The God Delusion and PZ Myers’ Pharyngula, for a while the most-read science blog on the internet. None of them influenced my decision because I had already become a convinced atheist before I encountered any of them.

Times have changed as the main protagonists have died, become caricatures of themselves, or merely declined in profile. It would be nice to think that people grew tired of hearing angry old white men argue with each other. They certainly didn’t succeed in making religion disappear and were likely a symptom of declining religious belief rather than its cause. While tempers on the subject have cooled, at the same time I have matured and become more reflective, and it’s now possible to look back on this period with a degree of detachment.

One of the ways in which leaving religion is described is as ‘losing your faith’. This is worth interrogating a little further. The Apostle Paul gives the following definition of faith, the only explicit one to be found in the Christian Bible:

Now faith is confidence in what we hope for and assurance about what we do not see.*

The basic point is that faith means believing in something despite not having complete or direct evidence for doing so. This seems as good a definition as any to me; I don’t know whether other religions have similar ones in their sacred texts. Put simply, you don’t need faith if you have incontrovertible evidence.

Much of the modern rationalist case against faith in general, and the Christian religion in particular, can be traced back to this verse. It is a prima facie example of how religious belief requires the absence of evidence, in contrast to scientific rationalism, which only allows for belief in things which can be directly proven. Religious truths are obtained through divine revelation, and are hence diverse, whereas scientific truths are produced via rigorous enquiry, which means that eventually they should hone in on a single answer.

The strongest proponents of scientific rationalism declare it to be impossible to be a true scientist whilst also holding a spiritual belief. This is clearly not the case; many scientists worldwide are religious. I know a good number and think no less of them. Whether the two positions are intellectually incompatible is not something I want to get into here, although I will note that we all manage to sustain contradictory viewpoints on many things. It has been claimed that biologists are less religious than other branches of science, but the evidence for this is inconsistent, and may to some extent reveal social norms within fields rather than any link with the subject material or mode of enquiry.

Regardless of whether I might describe myself as not having a faith, I expend a lot of my time believing fervently in things for which I have no direct evidence, at least not yet. What is ‘confidence in what we hope for‘ if not the anticipated outputs section of a grant proposal? Past evidence of over-ambition has not changed my approach to these.

As for ‘assurance about what we do not see‘, there’s more to this than believing the results of papers which we can neither replicate nor access the underlying data or code. Even were we able to do so, we usually lack time and resources to check. Instead we invest our trust in institutions (journals) or authority figures (other researchers) whose work we often accept without direct scrutiny. Given that we can’t check everything, we place confidence in the peer review system to rigorously inspect claims, despite personal experience of its occasional flaws. The difference between something I could check, at least in principle, and something I will accept without further question, is semantic insofar as how I respond is unchanged in practice. Such intellectual shortcuts are standard for everyone.

Moreover, our field (like most in science) is littered with fundamental theorems which work in closed or simplified systems but come unstuck when faced with the complexities of the real world. This doesn’t mean that they’re incorrect, but rather that uncovering the evidence for them is harder than we assume. If you’re an ecologist then perhaps ask yourself how often you’ve thought to directly test the logistic model of population growth, equilibrium model of island biogeography, Tilman’s R* or any number of theories which for many of us form the cornerstones of our understanding. If you have then my guess is that it didn’t go as smoothly as you hoped.** For the most part our evidence base derives from a surprisingly small set of case studies. Other theories for which the jury remains out (e.g. Metabolic Theory of Ecology) have advocates who by very definition are basing their belief on incomplete evidence given that other critical observers remain unconvinced.*** Is believing something because logically you feel it must be true that much better than accepting something without direct evidence?

A few weeks ago I stood on a seashore and stared at a rock covered in barnacles. The patterning was inconsistent with a model of their organisation which I’d published a few years ago. What went on in my mind was not a collapse in confidence but rather a reconsideration of what other processes or factors I might have been missing. I looked at that rock still believing in some version of the model even while the evidence in front of me so obviously disagreed. If I continue to work on this system then I remain certain that the model can be recovered, and have a few ideas of how to go about it. What is this if not a form of faith?

All this comes round to a recognition that perhaps I didn’t lose my faith; I simply realigned it by investing in a different set of principles and authorities. God disappeared from my worldview but maths and the scientific method took over. I may believe that my work is in pursuit of truth and serving a higher purpose****, but this this any different to those who follow a spiritual calling? In the last twenty years I have certainly changed but perhaps not as much as I thought.

* Hebrews 11:1 in the New International Version. The remainder of the chapter goes on to give historical examples of faith in practice.

** In writing this I am in no way questioning whether any of these fundamental theories is correct. Well, maybe the equilibrium model.

*** For the record, my take on metabolic theory is that it must be correct on some level but perhaps we haven’t been able to characterise natural systems in the appropriate way. I’m planning to have a chapter on this in the next edition of my textbook (don’t start getting excited just yet).

**** If you agree with me that understanding trees and barnacles represents a higher purpose then we really should be friends.

CODA: having swum in these waters before I know that taking a conciliatory line on religion and science is likely to see me being savaged by both sides. So let me be absolutely clear about my own position before anyone assails their favourite straw man. I am a scientist, humanist and atheist. I am convinced that the scientific process, whilst sometimes flawed and inefficient, remains the best means of deriving facts about the world. I hold no spiritual beliefs of my own but respect those who choose to and do not question their personal reasons. In response to this post I welcome constructive discussion that aims to increase mutual understanding but will not allow any comments which do not meet this standard, regardless of the viewpoint they seek to advance.

Writing about writing about decolonisation


Three privileged white men displaying the normal range of responses to calls for decolonisation of science. Still from 90s classic sitcom Friends.

Who gets to make the case for decolonisation in the sciences? One of the anticipated reactions to our recent paper on decolonising field ecology (written with Kate Baker and Mark Griffiths*, and summarised in this blog post) was that we’re just three white Europeans. What right do we have to comment? Aren’t we part of the problem?

The answer is that yes, we are the problem, and that’s why it’s our responsibility to draw attention to it. Dismissing our argument because we come from a position of privilege is like disputing evidence of a crime wave because you’ve only heard about it from the police. Why aren’t the victims making a fuss? Researchers from developing countries don’t have the same platform. We know that. We’re using our platform to make exactly that point.

Another way of phrasing the critique is: “We like what you have to say, we’d just rather it was being said by someone else.” At best this derives from an assumption that we are stealing attention which should be directed towards academics from developing countries. To which I can only agree, and point out that our main message is to point away and shout “Look over there!” We haven’t silenced or excluded anyone. If our paper opens up space for others to be heard then we will have achieved one of our goals.

We freely acknowledge that our line of argument isn’t novel; the whole point of the paper is to draw attention to how a movement originating in the social sciences hasn’t penetrated far in ecology. There have been powerful statements made in the past, some of which we cite, but it’s fair to say that their impact has been limited. Many appeared as magazine articles or were published in non-science fields, which means that a majority of researchers in ecology will simply never encounter them unless they deliberately go looking. We have instead placed a commentary in the principal journal of tropical ecology, a publication which mostly features conventional scientific papers, which is much harder to ignore.

Was it easier for us to do publish this paper than it would be for others? Yes, without a doubt. But that doesn’t mean it wasn’t worth doing. We gained our current positions through structural inequalities, but the system will only change if those in control of it make an effort to do so. We aren’t demanding action from scientists in developing countries, although we strongly advocate listening to them. The walls aren’t going to fall down just because someone’s shouting outside. We need to start dismantling them ourselves.

At its worst, criticising the profile of the authors instead of the message is a means of deflecting responsibility to act. Throughout history, most movements for social justice have foundered at some stage because those in positions of authority grumble that no-one affected has complained to them directly. It always takes calls from within the establishment to provoke a response.

Also, who’s asking? If your response to the paper is that you agree with the message, but that we’re not the right people to be saying it, then who is? Who gets to judge? This turns out to be another means by which established authorities control participation in discourse. I will gladly accept, and try to learn from, any criticism from those adversely affected by the colonial aspects of science. It’s notable that all the push-back I’ve had so far is from other white people complaining that white people are telling them what to do.

We have been asked why we didn’t invite a developing world author onto the paper. This is a source of regret to us as well, but we didn’t have one. The paper arose out of direct discussions between the authors which took place in the UK and determined the message and outline. Approaching someone post-hoc and asking them to stick their name on a manuscript would have been the worst form of patronising tokenism, merely serving to insulate ourselves from criticism rather than being genuinely inclusive. So no, we didn’t do that. Of course it would have been best of all to have incorporated a broad panel of authors from the start, but it would also be disingenuous to pretend that this happened. To criticise the paper on these grounds is once again dodging the message to score a moral point. I too wish that science was more inclusive and fully collaborative; that’s one of the points we’re making.

Finally, I’m happy to accept that I am not the right person to lead by example. My encounter with the decolonisation literature has come through an awareness and confession of past mistakes, most of which were made through arrogance and ignorance. By all means criticise me for what I’ve done wrong — I’m comfortable with my errors being used as instructive examples. I’m also stumbling into a new field and likely to make further blunders. This will be an iterative process and one I’m entering into with some trepidation. But I firmly believe that this is a necessary direction and hope that others will join us.

* None of my thoughts in this blog post are original; I’ve learnt everything from discussions with the other authors.

Remembering rhinos


Is this how we will remember the rhinos? Will it be any better than Dürer’s rhinocerus?

This autumn I will be teaching a new module in Conservation Biology. There’s a lecture I’m already writing in my head, though I dread the day that it finally happens because it comes with a personal dimension. I must be among a small number of living witnesses to two species which are now on the verge of extinction.

This week we learnt that Tam, the last male Sumatran rhino in Malaysia, has died. I met Tam while working in Borneo many years ago. My home was close to an institute that was attempting to breed rhinos and I would regularly walk past the enclosure hosting these recalcitrant giants on my way into the forest.

The story of the rhinos of Sabah is tied up with political disagreements, human tragedy* and some extremely bad luck. For many years it was asserted that there were 30 left in the wild, despite a persistent absence of evidence. Now we have to admit that they are on their way out. And no, I don’t have much hope for expensive lab-based interventions. If the habitat they lived in has gone, along with the accumulated knowledge and experience that allowed herds to move and forage through the landscape, then the species can only return as a curio. Limited conservation funding is better directed elsewhere.

By coincidence I also met one of the last of the northern white rhinos while teaching on a field course in Kenya 15 years ago. Not the very last, though this hardly matters, because their trajectory was already dismal. It lumbered peaceably around a bush and came directly towards me, staring directly down the barrel of my camera lens. Sadly I have no evidence of this because the film was subsequently ruined**, but I don’t need the photograph. The moment is seared in my memory for life.

In both cases I encountered the rhinos in sad circumstances. Tam was so domesticated by human contact that he was more interested in having a belly rub than in demonstrating his physical strength. He certainly wasn’t much interested in sex with other rhinos, which was the preoccupation of his keepers. The northern white rhino I met was accompanied at all times by a pair of armed guards. In neither case could I claim to have seen the species in its full glory. They were docile, amiable memories of rhinos.

These are the only rhinos I have seen outside zoos, although their absence is tangible in the increasing abundance of Euphorbia candelabrum in African savannahs, a generally unpalatable species but one which rhinos formerly consumed. Losing such a major herbivore inevitably has impacts on plant communities as well. If you know where to look then there is a rhino-shaped hole.

Yet my world is full of rhinos at the moment. My son plays with a plush cuddly rhino, has a soft blanket with a rhino print, wears a t-shirt covered with cartoon rhinos. The same could be said of dinosaurs, and what rhinos share in common is that they are large, charismatic megafauna which he will probably never see in the wild.

Yes, I know that there are positive stories to tell in rhino conservation. Global rhino numbers across all five species are close to 30,000, mainly due to successful protection of the southern white rhino in South Africa, but still the two Asian species hover on the brink, and a new poaching epidemic threatens recent gains.

And so, later this year, I will stand in front of a classroom of students and bear witness to the losses of my generation. We knew this was happening, we watched it happen, we tried to raise the alarm but our voices were not enough. The pressure is now building through movements like Extinction Rebellion and the realisation that this is an emergency. I hope that the tide is turning. Much remains to be saved. But even if we succeed this time, one day we will be forced to look back and see how much we have lost, plants and animals alike. I hope that I never have to describe a rhino.


Albrecht Dürer‘s famous 1515 print of a rhinocerus. It was drawn based on a written description of a rhino in Lisbon; Dürer himself never saw one. This fantastical image of a rhino nevertheless became wildly popular and shaped European imaginations of what a rhino looked like for centuries thereafter. Will our grandchildren know any better?


* My memories of the Sumatran rhino will also be tinged with sadness in recollection of the brilliant Dr Annelisa Kilbourn, a wildlife vet who died tragically in a plane crash in Gabon in 2002. Best known for her brave work demonstrating the link between gorillas and ebola, the rhino project was another large gap she left behind.

** At this point I might need to explain to the students that cameras used to contain film, before the arrival of digital mechanisms of capturing and storing images. This will only make me sound like even more of a dinosaur.