Some incredible fruits to be found here! Ended up with some guarana sirop, which apparently is better than caffeine if you're in dire need of energy, and - because it's the done thing in Guyane - some of the local rhum, mixed with squished pitaya (dragonfruit) and maracudja (passionfruit). Which was basically because they look irresistibly tempting in their bright colours. ;)
Cayenne itself is a small, nostalgic kind of city, parts of which look like they probably haven't changed since the 40s. The population of the whole of Guyane is only 250,000, so this isn't a vast metropolis - it's quieter, and still has a lingering colonial air about it... Probably something to do with all those wooden French buildings with their tricolores and wrought iron balustrades...
In the small Guyanese town we're working in, the rainforest apparently steps in if you forget to tidy the bedroom...
Think of the trillions of insect eyes in the rainforest between Cayenne and Manaus - so many tiny windows for tiny beings on worlds we will never know... Tropical forests are where all the mystery is.
Aujourd'hui j'ai regardé le coucher de soleil sur l'amazonie. Il y a de la grandeur dans cette vision de la vie.
Sorry for the delay in writing since my last post, but la vie guyanaise took a strange turn over the past week. Some small children stole half our equipment from a locked building at the research institute, which to be honest wasn't especially helpful. It's been a manic cavalcade of police interviews and missions to Cayenne to restore our equipment lists, surreally involving five gendarmes combing the house with forensic brushes for fingerprints. There were a few furrowed brows about how to get our radio-tags working without one crucial element, but fortunately I encountered a very slimy man in downtown Cayenne who has sold me an improbable-looking plastic device. Miraculously, it works! So many thanks to the slimy man.
We're busy attaching the radio-tags to the wasps, so some photos of the lovely wasps themselves are coming in the next post. For now, a few snapshots of life in beautiful French Guiana. Even with child thieves making off with your equipment, it's a wonderful place...
"Who on earth are they?" comes a heavily-accented voice from somewhere unseen. There's a pause. "Aha," it says a few moments later, in a knowing tone. "Les chasseurs des guêpes!" The wasp-hunters.
We seem to be becoming something of a curiosity. Every morning, after climbing out of the mosquito nets, driving north in style for an hour on French Guiana's only north-south road - flanked by the silhouettes of canopy trees and rainforest mists -, we start the day's work, which is basically the job of explaining to a gentle but relentless stream of bemused onlookers that we really have travelled over four-thousand miles to study their "mouches". I wish I had photos of all the bewildered expressions we've seen so far.
The little town we're working in has (apparently) been quietly getting on with life in the French Amazon since the 1620s. It's a rustic idyll of colourfully painted houses, many of which are made of wood and clay, on a wide meander surrounded on three sides by dense forest. There's a great community spirit. The town council have been fantastic, and it's a beautiful, tidy, and incredibly colourful town with a rich history. So, thank you Sinnamary!
We've found eleven houses across the town which host our fantastic species - and some of them (currently uninhabited) host such a profusion of colonies that's it's almost impossible to move through doorways given the risk that there's a nest on the hinges. Some of these abandoned houses, slowly but relentlessly being reclaimed by the tropics, have something strangely picturesque about them: there's one bedroom draped with hundreds of vines, broad-leaves springing up through the empty bedframe, and various wasp colonies clinging stubbornly but stylishly to the wall.
I'm currently doing a test of a method I plan to use in the actual experiment, which starts soon. Bring on the radio-tags!
Au revoir for now!
Today, whilst out searching for suitable field sites, I was unceremoniously attacked by Polybia rejecta - a different wasp species to the targets (victims? leading ladies? heroines?) of my PhD. That takes my PhD sting count from nought to six in one fell swoop. Ouch.
We're here and ready to start wasp-chasing! Drove to the field sites for the first time today - it's an hour's drive through the forest to a little village that been there since the 1600s, full of colonial houses painted in bright colours. And, of course, the odd wasp ;)
It's a strange thing to be finally going. Off to French Guiana, and its gorgeous wasps lurking on the forgotten frontiers of the French Amazon. I'm laden down, like some kind of Victorian naturalist, with vast piles of peculiar goods. Two-thousand-five-hundred sterile vials, seventy wasp-detecting radio-antennae, two-thousand radio-tags, two beekeepers' hats, twenty-four jump-lead crocodile clips, thirty-five metres of electrical wire, one letter of recommendation (French), a French phrasebook, a small flask of RNA preservative, a dissection kit, the names and addresses of my contacts in Guiana, and a sense of wild immediacy. Back to the tropics, with the dust and the sunsets, the crazed pageant of evolution, the sloths, the toucans, the caiman, the anteaters, the ants, the vast tropical trees stretching far above to the elusive canopy. It's a scary thing, putting a field trip on the ground under your own stream - at least, that's what I feel! But here goes! And so to the tropics!
When I first read Life on Air, the passage that made the most impression on me was Attenborough's first vision of the tropics as he landed at a small airport in Sierra Leone in the 1950s. It's magical being a tropical biologist. It's like stepping into this bonanza world where evolution has gone haywire.
See you in Guiana. P.
Every time I'm lured back to Oxford I seem to end up having a quick poke around the Pitt Rivers - the museum at the end of the universe. Shrivelled heads and totem poles, etc. This time, on a whirlwind visit before rushing to the station, I thought I'd try and track down a few objects from the Guianas considering I'm off to Cayenne on Thursday...
For your delectation, then, I present an arrow from the Maroni River (apparently collected by the Oxford ethnologist Audrey Butt Colson in the 60s, with a cryptic note attached about its past career as a murder weapon) and a quiver from (British) Guyana acquired in 1897. There's also a set of poison darts from the opening of the Pitt Rivers in 1884 hiding innocently in a dark corner of the upper gallery (also Guyana).
I'm sure the rest of the Guianas collections is pretty huge (the Pitt Rivers has so many objects the storage is supposedly larger than the museum...), but then, alas, I had to run for the train ;)
I love this picture. It's Charles Lagus, David Attenborough's friend and colleague, filming in 1955 for 'Zoo Quest to Guiana', one of the first forays the BBC made into natural history broadcasting. I've devoured 'Life on Air' several times... ;) But I haven't yet been able to watch 'Zoo Quest to Guiana'! The various other 'Zoo Quests to...' have all be put online by the BBC, but Guiana remains mysteriously absent. One day I'll get my hands on it. And yes I know that's (British) Guyana, not French Guiana, but it's such a great picture of the tropics that it makes me want to drop everything and be deep in the forest....
1 month to go till I slip away back to tropical storms and toucans. Preparations from afar continue... A taxi driver conversation today took a weird turn when he asked (in deep Bristolian) what I'm doing with my life. Turns out "trying to attach miniature radio-tags to hundreds of wasps around abandoned buildings on the edge of South American rainforests" is a hilarious answer. Cue a long drive to Temple Meads station with the taxi driver doubled over in hysterics.
I won't give away exactly what I'm doing, in case other South-American-abandoned-building-wasp-radio-taggers (?) go in for a bit of industrial espionage. (Though I suspect that isn't too much of a risk.) In short, there's a fascinating evolutionary mystery concerning animal cooperation that we're interested in at Bristol, part of a rich tradition in evolutionary biology stretching back to the greats like W. D. Hamilton and John Maynard Smith. It's fantastic to have the chance to explore this enigma in high resolution using techniques like radio-tagging on wild populations.
I'm finding it an interesting exercise setting up a field project from abroad! Logistics are just about sorted now. And I'm very much looking forward to meeting Professor Alain Dejean (of the University of Toulouse) and Dr Bruno Corbara (Global Canopy Programme), who are both kindly lending their advice in French Guiana.
That's all for now then. Ciao!
Imagine you and some friends really really want ice cream. But to get it, one of you is going to have queue for hours. Someone has to take the costly plunge. Who will do it?
This kind of scenario - the 'volunteer's dilemma' - is the sort of thing that arises when only one individual (or, at least, a set number) is needed to generate a public good. In this case, it is ice cream for everyone. If nobody volunteers, nobody gets ice cream. If somebody volunteers, they can do the queuing. It pays everyone else to remain silent. Nobody wants to queue for hours.
The volunteer's dilemma has recently been under a bit of scrutiny in the context of punishing cheats. When you've got a group with more than two actors (an n-player group), and a cheat arises, that cheat can be deterred from cheating in the future if they are punished. The positive pay-off from preventing cheating is a public good, the benefits of which are shared across the group. But who will step up and pay the personal cost of punishing the cheat? Exotically, we end up with what we call a 'second-order' cheating problem: it pays to free-ride on the goodwill of someone else who'll punish the first free-rider (1). To keep with the ice cream example, it's like somebody has stolen everyone else's delicious chocolate 99-flakes, but nobody particularly wants to step up to punish them because it's a costly behaviour that will be injurious to them (let's say it involves a bit of a punch-up), even if it benefits everyone by deterring 99-flake thieving in the future.
There are two main ways the pay-offs in this second-order problem can work. It could be that more punishers means a proportionally better result. Or it could be that only one punisher (or, in more complicated set-ups of the volunteer's dilemma, a set number of punishers) are needed. The first is an n-player prisoner's dilemma scenario; the second is an n-player volunteer's dilemma. Another way of describing this is to say that the former is based on a linear pay-off function, whilst the latter relies upon a non-linear, binary pay-off function, which makes a sudden change at a certain level of punishment. There are, of course, a number of intermediate non-linear functions.
Let's imagine the n-player volunteer's dilemma in its simplest form, in which only one volunteer need step up in order to achieve the step change in pay-off to the group by getting on with the punishment. The evolutionary outcome of such a game is that both second-order free-riders and second-order volunteers persist in the population at equilibrium, and perturbations from this equilibrium result in a return to it (i.e. it is evolutionarily stable). Why? Because fitness in this game changes in a negatively frequency-dependent fashion. To see this point, have a think about this: the fitness pay-off of being a volunteer in a population where everyone is free-riding is higher than being a free-rider, but the fitness pay-off of being a free-rider in a population where everyone is volunteering is higher than volunteering.
There's a school of thought that says the volunteer's dilemma is a much more realistic vision of punishment than the prisoner's dilemma. Nichola Raihani and Redouan Bshary, for instance, think that we should expect the real world to involve step-changes: a set number of individuals should step forward, and any more would be silly, increasing the cost to the group for no gain (1). In the prisoner's dilemma (i.e. when the pay-off function is linear), we end up with free-riding winning unless individuals are able to assort in some way (such as by grouping with relatives, or remembering reputations). Non-linearity creates a stable mixed equilibrium through negative frequency-dependence (unless the cost of punishing is simply too big), so does away with the need for these additional assumptions (2).
The next step is demonstrating that such non-linearity of pay-offs is common in real punishment situations. Recognising this non-linearity may help transform our understanding of public goods problems, so watch this space!
To find out more!
(1) Raihani, N. & Bshary, R. 2011. The evolution of punishment in n-player public goods games: a volunteer's dilemma. Evolution, 65: 2725-2728
(2) Archetti, M. & Scheuring, I. 2010. Coexistence of cooperation and defection in public goods games. Evolution, 65: 1140-1148
You are a bacterium, and you are strenuously trying to persuade a squid to go into business together. The way you see it, you're a match made in heaven. You've got something bobtail squids want - the funky skill to produce bioluminescent light - and a squid could offer you a home. Only problem is: how does a humble bacterium convince a squid to take it on?
Evolution really likes signals of quality (just ask a peacock to show you his tail). To be believable ('credible'), these signals need to be costly. But the quirky, counter-intuitive world of handicap signals - famously proposed by Amotz Zahavi in Israel and mathematically elucidated by Alan Grafen at Oxford - is a story for another time. It involves individuals demonstrating their quality to a discerning watcher through a costly exhibition of quality that can only be borne by high-quality individuals. Since you are a bacterium trying to enter a bobtail squid, you're soon going to run up against a close cousin of costly signalling, a form of costly honesty known as 'biological screening'.
Screening occurs when the watcher actually imposes a costly task upon these individuals, like King Eurystheus imposing intense tasks upon Hercules. Again, we end up with an honest exhibition of quality: low-quality individuals will simply fail the test, so screen themselves out.
Your squid has set you a biological gauntlet: only high-quality individuals like yourself can run the gauntlet. Cleverly, this is because life within the internal niche set aside by the squid for bacterial applicants carries a risk of death from a bunch of chemical nasties called reactive oxygen species (ROS). Bacteria that carry out the task the squid wants - bioluminescence - do so with the enzyme luciferase, and actually using your luciferase ends up reducing ROS generation back down to safe levels. Thus, the squid screens its bacteria: those who fail to work simply cop it. This brutal job-hunting game was highlighted as a case of screening in the real world four years ago by Marco Archetti (1).
Archetti and colleagues also highlighted a peculiar form of screening they christen 'competition-based screening' (2). In this case, the applicants have to struggle against one another in an arena created for the purpose by a host. As an example, they offer the famous mutualism between acacias and ants. A little acacia colonised by a bunch of different ant colonies in different regions of the plant might find that colonies differ in their usefulness as defence against herbivores. The idea is that those regions of the acacia with useful colonies will grow better than those without, and eventually only the good colonies will be left.
My own PhD is on wasps (which, incidentally, means I have to spend a huge amount of time arguing with people who advocate mass waspocide). Archetti's ideas on competitive arenas remind me of a strange theory concerning the swarm-founding wasps of South America, who rush the building of their nests ('explosive nest construction'; 3). There are a few hypotheses for this behaviour kicking around, including that it is simply a good idea to protect your brood from the slings and arrows of the world by building your nest quickly. Another, however, is that building the nest hyper-quickly is a means through which workers (seemingly unable to nepotistically favour queens based on relatedness) deliberately create manic competition amongst hopeful queens in order to select them based on fecundity: those who can't exhibit their fecundity (by laying loads of eggs in the shiny new array of empty nest cells) end up excluded as candidates for the eminent role of reproducing (3,4).
So, next time you're taking on a new job, be thankful: if you were a bacterium, a moments slacking might spell death, if you were an ant colony you might die for not keeping up with the Joneses, and if you were a wasp queen you might be pumping out eggs like there's no tomorrow. Perhaps interviews don't seem that scary after all.
To find out more!
(1) Archetti, M. 2011. Contract theory for the evolution of cooperation: the right incentives attract the right partners. Journal of Theoretical Biology, 269: 201-207
(2) Archetti, M., Scheuring, I., Hoffman, M., Frederickson, M., Pierce, N., & Yu, D. 2011. Economic game theory for mutualism and cooperation. Ecology Letters, 14: 1300-1312
(3) Jeanne, R. & Bouwma, A. 2004. Divergent patterns of nest construction in eusocial wasps. Journal of the Kansas Entomolgical Society, 77: 429-447
(4) Loope, K. & Jeanne, R. 2008. A test of adaptive hypotheses for rapid nest construction in a swarm-founding wasp. Insectes Sociaux, 55: 274-282
Three months fieldwork in semi-rural areas on the north-east rim of French Guiana. We will be investigating colony structure in Polistes wasps. See this page for more information and how to apply.
I've just been demonstrating in a first-year undergrad practical exploring crayfish, earthworms, and tadpoles. Fairly early on, somebody declared that they were finished early. In desperation, I cast around for something interesting to keep them occupied - and what better than pointing out one of the great, eerie differences between the crayfish/earthworms on the one hand and something very peculiar about the tadpoles...
My mind was blown on several occasions at Oxford - including when somebody pointed out that, cladistically, we're sarcopterygian fish. But one glorious biological tidbit that really sent the neurones reeling was the radical theory of 'dorsoventral inversion': the crazy idea that, sometime before the origin of the chordates, our distant ancestor flipped upside down.
The mystery is this. In protostomes (one of the two great divisions of animal life - the branch of the evolutionary tree that hosts insects and spiders and squid and so forth), the nerve cord is on the underside of the animal. But in chordates (the group that we're in), it's on the upperside. In other words, it's ventral in the protostomes, but dorsal in us. Since we're descended from a common ancestor, something odd has gone on here.
During the French Enlightenment, the fabulous Etienne Geoffroy Saint-Hilaire pointed all this out. The solution later proposed was that there was a general flipping-over at some stage in evolution. Admittedly, this does sound a wee bit barking, and was unceremonially relegated to the waste-paper bin of evolutionary theories. But now - stunningly - 'dorsoventral inversion' is experiencing a shocking return to the limelight! The molecular evidence truly does look as though the cross-sections of protostomes and chordates are undeniably symmetrical (have a look at this very clear diagram - admittedly a Wikipedia offering, but that means I can reproduce it here without copyright...):
It really fired my imagination when I first encountered the idea, and it still does. It looks like somewhere in deep time, the lives of our ocean-dwelling ancestors were - literally - turned upside down. Which is why I'm sharing it briefly here. Hopefully the fast-paced undergrads in the practical thought that was suitably exciting...
Somewhere in the distant canopy, a howler monkey is howling. It’s a primordial, guttural moan, like an out-of-date soundtrack to the Jurassic. Meanwhile, down here on the forest floor, something is lolloping silkily in my direction. I freeze. It’s a tamandua (the Andrex puppy of the anteater world), and it hasn’t seen me. It’s fixated hungrily on the ground, and, still oblivious, saunters off into the packed undergrowth.
Minutes later, feet immersed in a rocky stream, I’m gazing at the improbable, spindly legs of a giant walking palm. The walking palm is an almost mythical being. It is said that, as the decades pass, the palm strides languidly through the forest by extending its numerous stilts - evolution’s answer to Miyazaki’s itinerant Forest Spirit. I stare at this unlikely nomad, trying to imagine its slow-motion (and controversial) passage through the trees.
Ruining the soundscape, I am loudly and aseasonally humming Good King Wenceslas. This is a dubious attempt to scare off lurking snakes. I feel slightly silly. It clearly isn’t working, because despite the racket I’ve seen two coatimundi, the flash of a deer, a curious-looking capuchin, and a wandering agouti. Snakes aren’t the only vague fear in this forest: ‘researchers,’ reads a serious-looking sign back at the guard’s hut, ‘are reminded of the possibility of encountering live ordnance’. American troops apparently tested their weapons here before dropping them on Vietnam. I decide not to think about it.
Later in the afternoon, the heavens open: as always, the morning sun has fuelled evaporation from the limitless trees, and the lost water has amassed as clouds before returning dramatically to earth. Sheltered slightly by the canopy, I watch an anole lizard position itself grandly on a log, and, as if from nowhere, extend a brilliant, peach-tinted fan of scales from the underside of his neck. He retracts and inflates the elegant billboard repeatedly, only stopping to nimbly chase an upstart intruder from his claimed territory. Is a female lurking somewhere in the shadows, coolly appraising this exuberant display? I do not know.
Maybe rainforests are addictive. I wrote the above in a gush of excitement - in the midst of a torrential storm - after coming in for the night from the forest. I’ve just spent two nights at one of our wettest field sites, and, after working alone in the forest for hours, it’s really hit me just how much there is to see. Perhaps rainforests are like Pringles: once you pop, you just can’t stop…
An interesting question: isn't it a little bit strange that, after thousands of years of intense pondering about where we came from, the remarkably simple solution - evolution by natural selection - occurred independently to a handful of people in one particular society in the space of a couple of decades?
From the workhouse to the forest?
That particular society was, of course, the crucible of modern capitalism: Victorian Britain during and following the Industrial Revolution. This was a world where competition, inequality, and ruthless self-interest (core ingredients of evolution by natural selection) were writ large and writ aggressive. It's not exactly rocket science to suggest that the idea of natural selection could only have been born in a society where the struggle for existence was already in the air - and on the streets.
Richard Lewontin, the controversial Harvard biologist famous for Biology as Ideology, pointed out that this link was to some extent actually acknowledged by Darwin himself. Both Darwin and Wallace report that they came to their revelations after reading the frankly horrible essay On The Principle of Population by an unpleasant curate known as the Reverend Malthus. Observing coolly that the poor were proliferating, Malthus anticipated a so-called 'Malthusian catastrophe', where an over-sized population is cut to a sustainable level by, essentially, a lot of death. Nature works in the same way, remarked Darwin and Wallace: there simply aren't the resources for every animal to survive and reproduce, so - in the free market of nature - only those most capable of surviving and reproducing will in fact do so.
Fast-forward to the 1980s...
In a sense, sociobiology solved the mystery of altruism by refocussing our understanding of the struggle for existence: the real struggle is there, but rather hard to notice at first, taking place between genes. In the evocative words of Richard Dawkins, genes are the 'replicators', and we - the organisms - are the 'vehicles' they've built, machines constructed out of convenience to carry out their interests in the world. Dawkins' The Selfish Gene is the book that absolutely gripped me about biology when I first read it, and it's the reason I decided to pursue biology at university, so I hope you don't mind if I quote a little of it. In a famously stirring passage (which Dawkins later blushed a little at writing), the extraordinary picture that sociobiology painted is captured beautifully:
As with Darwin and Wallace years previously, those working at the coal-face weren't unaware of the political zeitgeist and it's possible influence on science. Dawkins, indeed, has explicitly discussed his bemusement after, in 1979, the neurobiologist Steven Rose declared (a little bit turgidly):
Dawkins' answer was that, of course, 'we should not derive our values from Darwinism, unless it is with a negative sign' (p.xiv of the 30th Anniversary Edition). He certainly isn't a Thatcherite himself (in fact, he's a public supporter of the Lib Dems). In any case, his is a crucial and much-needed point: Social Darwinism is toxic and unacceptable, but that has nothing to do with the science of evolutionary biology. Evolutionary biology is concerned only with the natural world. This answer is of course correct. But it doesn't address the uncomfortable question of whether or not right-wing environments have fostered developments in evolutionary theory.
So is there an unconscious link?
I think it's very possible that there is such a link. But then, we should be careful not to draw casual correlations: these very same decades saw the rise of the radical 'Gaia hypothesis' in England and America, a decidedly more hippie vision of the world as a self-regulating entity, a metaphorical Earth Goddess maintaining the conditions for life. We can hardly ascribe that to Thatcher.
There are alternative arguments. The celebrated German biologist Ernst Mayr proposed that the secret to why Darwinism appeared so late in the game was that, ever since Plato, Europe had been in the grip of 'essentialism': the idea that there is, in some sense, a true essence of the camel, a true essence of the duck-billed platypus, and so on. In the famous 'Allegory of the Cave', Plato (through the voice of Socrates) describes a bunch of prisoners staring at a cave wall. On the wall are thrown the shadows of various strange things, but the prisoners - who have been stuck in this cave all their lives - have never seen these things themselves. The things themselves are the 'Forms', abstract, ethereal entities that constitute the true objects of reality. Mayr argued that the 'Theory of Forms' held sway over biology for centuries. We were indisposed to even imagine evolutionary change, because accepting the 'Forms' implies that species are immutable.
The phrase 'evolution by natural selection' has, obviously, two parts: (1) evolution and (2) natural selection. If Mayr was right, then the problem of why Darwinism took so long to appear presumably isn't to do with the fact that natural selection was hard to come up with, waiting to be found by a culture of hyper-capitalism. Instead, the problem would be with the first part: coming up with evolution was the problem, and it was only by the erosion of latent Platonism that it could appear on the scene. Natural selection followed shortly after, a quick and simple solution to a new and pressing question.
Basically it's all apparently very complicated.
This is the point where I throw my hands in the air and decide it's all a bit over my head. Perhaps there is a clear link between politics and evolutionary biology (notwithstanding the all-too-obvious connections with eugenics) - it wouldn't be the first time science and politics were intimately interwoven. But then again, in the bubbling soup of post-Enlightenment exuberance, colonialism, ideology, and frenzied economics of Victorian England and the Cold War west (the latter aided by a sprinkling of counter-culture excitement), perhaps the links between politics and science are just too blurred and subtle to find out. But I'd be really interested to know...!
I'm a biology student, so - obviously - I'm slightly in love with Darwin. And I've recently been exploring these incredible websites: 'Darwin Online' and 'The Darwin Correspondence Project' from Cambridge. Together, they're a pretty much a complete virtual library of everything Darwin wrote, and that was a lot. In fact, I can't believe quite how varied his output was. Besides quietly coming up with the greatest idea in the history of humanity, he was also beavering away on essentially every mystery going, including the origin of coral reefs, the nature of hedgehogs, the arcana of duck skeletons, the geology of the ocean floor, the role of volcanoes, the source of tiny Saharan microbes appearing on ships in the middle of the Atlantic, the size of Jamaican bees, the 'civilisation' of 'South American savages', and whether or not Chinese children pout when grumpy. What a man.
Evolutionary biology was born in the tropics
A bit of background quickly. Around the reign of Queen Victoria, three people suddenly came up with the idea of natural selection independently.
The first was an obscure Scottish writer called Patrick Matthew, who penned a few musings at the back of a boringly technical book on ship-building and then kicked up a fuss when it turned out nobody had actually read them. Let's quietly forget about him.
The second was, of course, the great Darwin himself, largely inspired by his travels in South America.
And the third was Alfred Russel Wallace, an eccentric, spiritual, and bearded English traveller, chasing butterflies alone in the rainforests of the Far East. The great idea came to him - like a revelation - in the midst of a malarial fever on a remote Indonesian island.
It's probably not that surprising that two of these three came to their genius realisations during or after a sojourn in the tropics, given the exuberance of life here. I decided, then, that it would be interesting to use the 'Darwin Online' and 'Darwin Correspondence Project' libraries to delve into Darwin history and find out just what the great man thought of tropical rainforests...
Wide-eyed in the 'primaeval forests'
First things first. In his public account of the three-year HMS Beagle expedition, the young Darwin eulogises the forest:
Young Darwin is full of such wide-eyed wonder at everything. It's fantastic to read The Voyage of the Beagle, because so much of it is packed with excitement and curiosity about the things he finds around him. Decades later, however, after a difficult life as a reluctant revolutionary, the old Darwin is tired and world-weary, and I've found this rather sad passage in his autobiography:
This mournful, aged Darwin goes on to claim that his young excitement 'was intimately connected with a belief in God' and 'did not essentially differ from that which is often called the sense of sublimity' (p. 92). Having painfully lost his faith, old Darwin claims he lost the 'sense of sublimity' too.
I'm not sure quite how much I believe all this. Imagine the fresh Cambridge graduate, standing for the first time on the shores of Patagonia, or the rocky outcrops of the Galapagos, or a ridge surveying a rainforest in Brazil, and it's hard to believe that this energetic genius with such a sense of constant curiosity for the world wouldn't be just as moved as he was, whether or not he had the faith. But who can tell?
In any case, it's true that old Darwin still loved the forests, and, indeed, a mere ten pages earlier in his autobiography he mentions that same 'the sense of sublimity':
Did rainforests sow the seeds of revolution?
Darwin in the rainforest was overwhelmingly excited about the sheer diversity of species. Surely this must have been important in his coming to see the natural world not as harmonious and ordered but as competitive, ruthless, and fundamentally selfish. The manic scramble for light taking place amongst rainforest trees is about as clear an illustration of 'the struggle for existence' as you can get. It's interesting to note, though, that in the final paragraphs of 'The Origin of Species', Darwin doesn't turn to the rainforests for an easy and powerful image of nature's intricacy and diversity. Instead, he picks a scene much closer to home: the woody banks of Kent. Just because they're so wonderful, here are those famous lines:
Jilted by 'the prettiest, plumpest, most charming' girl in the land
There's a further twist to the rainforest tale, argued and laid out in brilliant detail at this link by Eric Simmons. I'll summarise it here. Basically, before he married his first cousin, Darwin had a love interest in the form of a local friend called Fanny Owen:
They should make this into a film.
So the story of Darwin and the rainforests has everything: God, jilted lovers, jealously, and the germs of Darwin's gradual steps towards changing the world. They really should make a film of all this.
Is it a mini handbag? A tiny saddle? A giant hamburger for Lego people? The eye of a Colombian vulture? May I present the seeds with a thousand names...
However, there is very similar genus of legumes called Mucuna, and after a bit of rummaging around I've come to the conclusion that this is Mucuna mutisiana (we'll of course check this with an expert at identification at STRI).
Not to be outdone by Dioclea, Mucana has a lot of quirk going for it too. It's also a seabean, and it's name apparently comes directly from indigenous languages. Some members of the genus are apparently popular amongst the spectacular Morpho butterflies you often see fluttering along trails. The diversity of random uses to which Mucuna has been put are almost ridiculous, including (if we trust Wikipedia here) possibly-hallucinogenic shamanic snuff, herbal remedies for Parkinson's, aphrodisiacs in India, a useful nitrogen-fixer for Guatamalan farmers, a 'cognition-enhancing' drug, and prank powder that makes you itch loads. Which is interesting, because if you'll excuse me, I now need to go and remove a very large number of tiny Mucuna spines from my hands.
Stop press! An hour after writing that, I've just looked inside the pod of another Mucuna, and there was a small, dead scorpion inside... o_O The plot thickens...
Hi! I'm Patrick - an early-career postdoc in behavioural ecology. I completed my PhD in 2019, focused on Polistes paper wasps in South and Central America. I'm currently a Marie Skłodowska-Curie Fellow and Simons Society Junior Fellow in the Rubenstein Lab at Columbia University (New York) and the Radford Lab at the University of Bristol (UK), looking at the social behaviour and evolution of Africa's incredible wasps! I'm always keen to get involved in outreach to spread the word about these amazing animals.
Patrick Kennedy, University of Bristol
A blog about research, fieldwork, and trying not to get stung by big tropical wasps too often