Mistletoe Magic

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The European mistletoe is a hemiparasite that steals water and nutrients from host trees, but whose green leaves photosynthesize and produce sugars as well. Photo by: Hans Braxmeier

T’is the season here at the BioPhiles and this week’s species extraordinaire is the European Mistletoe of Christmas carol fame, Viscum album. Its dark green foliage and shiny white berries make it perfect for decking the halls and creating holiday romance, but from a biologist’s point of view, this Christmas standby is no slouch, either. Like all mistletoes, it is a parasite of other tree species and its roots have been modified into specialized structures called haustoria that penetrate the host’s bark, allowing it to divert water and nutrients from its host. Despite being a perfectly adapted thief, the European Mistletoe is considered a hemiparasite because it still retains the ability to photosynthesize and is not dependent on its hosts for all of its nutrition. Nevertheless, heavy mistletoe infections can drastically alter the physiology of their hosts, decreasing water use efficiency, and increasing nitrogen demands. This can ultimately change total biomass production of the tree as well as the relative proportions of leaves, wood, and roots it produces.

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Mistletoe seeds are surrounded by sticky viscin that helps them to adhere to branches where they can germinate and infect new trees. Photo by: M. Fagg

The white berries produced by mistletoe are another highly adaptive feature of this plant. The seeds inside the berry are surrounded by sticky flesh called viscin, which contains sugars and long, tightly coiled fibres called cellulose microfibrils. This combination of molecules allows viscin to both stick and stretch. Viscin is a sort of botanical superglue: it doesn’t dissolve in water and isn’t easily broken down by heat, light, or even the digestive tract of birds. When birds eat the mistletoe berries, the seeds that are defecated out are as sticky as when they went in, allowing them to adhere to whatever branch the bird was sitting on when it answered the call of nature. Not all of the seeds make it that far either. The sticky viscin coating often leaves mistletoe seeds stuck to the beaks of birds, which induces preening behaviour. The bird will wipe its face against branches until the offending seed comes off, and the viscin will glue the seed to the branch where it can germinate and start a new infection. This is where bird behaviour becomes important in shaping mistletoe populations. The plants largely depend on birds to disperse their seeds. Because birds prefer to visit trees with tasty mistletoe bushes growing on them, a positive feedback loop initiates, whereby mistletoe populations become concentrated in small patches, and trees have multiple infections. From a biologist’s point of view, the magic in the mistletoe has nothing to do with Christmas cheer, it’s parasitism and adaptation.

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A positive feedback loop driven by bird behaviour means that a tree with one mistletoe infection is likely to develop more. This poplar tree has many globe shaped mistletoe plants growing on its branches. Photo by Stefan Schweihofer

 

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Who’s Reading Scientific Articles?

Hey readers, where do you get your science? Dr. Paige Jarreau (@FromTheLabBench) from Louisiana State University wants to know! I’ve teamed up with Dr. Jareau, the Canadian blog network Science Borealis, and 20 other Canadian science bloggers to conduct a broad survey of science blog readers. We want to know who’s reading science, where they’re from, what content is important to them, and what your trusted sources for science are.

The survey takes just 5 minutes (I did it myself) and is one click away: Science Blog Survey

The rewards are well worth it too: complete the survey and you automatically receive a free hi-resolution science photo from Paige Jarreau. You will also be entered to win one of eleven prizes including giftcards and Science Borealis T-shirts. Thanks in advance for taking part and helping out Dr. Jarreau’s research!

Dr. Jarreau is interested in who is reading science blogs, but this made me wonder who actually gets their information straight from the scientist’s mouth. Who actually reads academic papers? In 2014, Nature published an article about the top 100 papers of all time, which included the infographic below about the literal mountain of research papers in existence. Stack the first page of every article in Web of Science together and you’d have a pile nearly 6000m high, as tall as Mount Kilimanjaro. Forty five percent of those papers, a 2500 m mountain’s worth, have never been referenced by another scientist. At first glance, this would be enough to make any scientist’s heart plummet. ‘Scientific knowledge’ isn’t so much a textbook, as an intricate web of conversations between researchers talking to each other across space, and across time, all played out in academic publications that make reference to and build upon the scientific work of others. But quite literally millions of publications are not finding their way into this scientific dialogue, representing hundreds of millions of man-hours and scientific sweat, blood, and tears. Can it be true that scientists haven’t actually read half the science produced in the world?

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Scientists have produced a mountain of research, but nearly half of it is never referred to again. This raises the question: Do scientists actually read academic articles? Photo by Kyle Bean; Design by Wesley Fernandes/nature

Figure 3

Response dynamics (Twitter mentions and arXiv downloads) for a selected arXiv preprint.ArXiv downloads often peak shortly after Twitter mentions peak. Figure from Shuai et al. 2012.

In reality, the picture is not nearly as dire as Nature’s ‘paper mountain’ might suggest. Not everyone who reads a scientific paper actually cites it in their own research. If you look at the top three papers in 2014 identified by altmetrics (an alternative method of ranking the importance of scientific publications), each one was downloaded tens or hundreds of times, was covered in traditional mainstream news media, and was shared or mentioned thousands of times on social media. But their citation numbers are modest: between one and fifty times. Clearly citations ≠ readership. So does this mean researchers can relax and need not worry that their hard work has good chance of being relegated to a dusty library shelf or a dark corner of an electronic repository, never to be read again? Not exactly. Global scientific output has been doubling every decade meaning papers are being published at a rate of three every minute and new scientific journals are launching every year. The competition to be noticed in this sea of science is intense, and it is easy for a research article to get lost in the jumble. So what’s a scientist to do? Public relations seems to be the answer. There is a well-documented link between download rates and promotion of scientific papers through social media and traditional press releases. When a paper is tweeted or featured on the evening news, download rates spike shortly thereafter. To stand out in the mountain of scientific papers in existence, researchers need to advertise and find an audience for their work, not just publish and wait for an audience to stumble upon it themselves.

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Perfect Patterns: Science in Autumn Leaves

autumn-493788_1920The bliss of crisp air, golden light, and the deeply satisfying scuffling of shoes through piles of dry leaves is what makes autumn my favourite season. The fall leaves are especially fascinating to me. A few cold nights can make the trees burst into flaming golds, oranges, and reds, all evidence of chemistry and physics in action. The degradation of chlorophyll, the green pigment in leaves, unmasks these vibrant hues, and there’s something poetic about the death of one chemical compound letting a leaf’s inner beauty shine through*. The changing seasons reveal leaves’ beautiful colours, but if you look more closely, another gorgeous phenomenon is apparent. The intricate pattern of veins in the leaves is often highlighted in contrasting colours, revealing the complex transport system the plant uses to move water and nutrients around its tissues and another bit of perfect natural geometric beauty.

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Developing leaves with the cells transporting the plant hormone auxin stained blue. As the leaf matures, an increasingly complex system of canalized auxin flow develops, which ultimately gives rise to the pattern of leaf veins in a mature leaf. Photos from: Dengler and Kang 2001

The mechanism behind the formation of these patterns is a source of fascination for scientists. The current prevailing theory of how these patterns are formed is based on hormone transport. Plants produce a hormone called auxin, which is thought to promote young leaf cells to differentiate into the specialized vascular tissues that form the veins in a leaf. The ‘auxin canalization hypothesis’ proposes that young plant leaves produce large amounts of auxin, and when a cell produces a large amount of the hormone, it is stimulated to absorb more of it from surrounding cells. The net flow of auxin in the plant is downwards, from the leaves, into the stems, and down to the roots. The positive feedback loop that results from a strong auxin producing cell absorbing the hormone from around it and passing it downwards creates a canal like system of auxin transporting cells in the young leaves. Ultimately, auxin hormone levels in these canals reach sufficient levels to trigger the cells to differentiate into vascular tissues that are specialized for transporting water and nutrients around the plant. The result? The complex canal system for polar auxin transport from the leaves to the rest of the plant ultimately becomes the beautiful pattern of veins on a leaf.

But science is never simple, and leaf venation patterns are not an open and shut case of hormone transport and cell differentiation. Micro-RNA molecules act as developmental signals in leaves, and they seem to play a role in determining the top and bottom of the leaf, as well as the formation of the leaf blade versus its stem, or petiole. Mutations in this micro-RNA signaling pathway also causes disrupted vein patterns, suggesting proper leaf shape is important to forming the regular geometric patterns of veins in a normal leaf. Similarly, there is a growing body of evidence that growing leaves are under mechanical stress due to tensions created by the different mechanical properties of veins versus blade, and the outer epidermal tissues and inner mesophyll tissues of the leaf. Modeling these stresses in leaves shows that vein formation matches patterns of maximum compressive stress, suggesting that mechanical forces may actually act as signals for vein formation. Whatever the mechanism behind these patterns, autumn leaves are another reason why biology is beautiful!

*Read more about the chemistry of fall colours on Compound Interest 

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Evolutionary Outsourcing – Using Symbionts as Vitamin Factories

This entry is part of a recurring series called Use It Or Lose It that looks at those things that didn’t make the evolutionary cut and have been lost in modern species.

‘Eat your carrots, they’re good for your eyesight’ was a common refrain at the dinner table when I was growing up. As an adult I now know this was a child-friendly explanation that Vitamin A deficiency causes blindness, and this can be prevented by a healthy diet that includes carrots. Over the course of evolutionary history, humans, like many insects and animals, have lost the ability to synthesize the vitamins they require to live. This represents an evolutionary process known as compensated trait loss, whereby an organism loses an essential ability but continues to survive because some aspect of their environment or other behaviour compensates for the loss.

Sharpshooters are among those insects that subsist exclusively on a diet of plant sap. They depend on endosymbiotic bacteria to synthesize many of the essential Vitamins they need to survive. Photo by: Andreas Kay

Sharpshooters are among those insects that subsist exclusively on a diet of plant sap. They depend on endosymbiotic bacteria to synthesize many of the essential Vitamins they need to survive. Photo by: Andreas Kay

In the case of humans and many other mammals, a diet rich in vitamins compensates for the loss of vitamin-producing abilities: eating carrots compensates for not being able to synthesize Vitamin A. By contrast sap-feeding insects like leafhoppers, aphids, and sharpshooters, who subsist on little more than sugar water would seem unlikely candidates to lose the ability to synthesize vitamins in their own cells. The same goes for blood-feeding insects like tsetse flies. Despite their extremely uniform, vitamin-poor diets, these insects are nevertheless unable to synthesize most vitamins and even some essential amino acids.  It’s a perfect example of how evolution can take many roads to the same destination. In this case, the key to surving an evolutionary breakdown in vitamin biosynthesis is not a rich diet, but evolutionary outsourcing. Over millions of years, symbiotic relationships have developed between these organisms and bacteria living within their cells that are collectively called endosymbionts. For example, the tsetse fly has bacteria belonging to the genus Wigglesoworthia*, living freely within its cells. These endosymbionts have the ability to produce Vitamin B, which is then transferred to the fly. This obligate association between the bacterium and the insect has driven the tsetse flies to lose the ability to synthesize the vitamin, and allowed it to succeed with a restricted blood-only diet that does not provide all of its essential nutrients. The story of sharpshooters, leafhoppers, and aphids is much the same: all of these insects feed exclusively on plant exudates or sap that are poor in nutrients, and compensate for their own inability to synthesize vitamins by harnessing the vitamin manufacturing power of endosymbionts.

Olavius algarvensis is a marine worm that lives in sediments. It has no mouth, gut, or anus, and gets all of its nutrition from chemoautotrophic bacterial that live within it. Photo by: C. Lott

Olavius algarvensis is a marine worm that lives in sediments. It has no mouth, gut, or anus, and gets all of its nutrition from chemoautotrophic bacterial that live within it. Photo by: C. Lott

The exploitation of endosymbionts as vitamin factories is not limited to insects either: examples of similar dependencies can be found among animals and fungi too. However, by far the most extreme examples of evolutionary outsourcing come from deep below the sea. There are few species that are able to survive in deep ocean sediments, where there is little oxygen, no sunshine, and few available nutrients. Oligochaete worms like Olavius algarvensis thrive in this harsh environment by using endosymbiont bacteria that live under their skin to do the heavy lifting. The relationship between these two organisms has become so specialized that the worms are wholely dependent on their associated bacteria for their nutrition. The endosymbionts are chemoautotrophic, meaning they harness chemical energy to produce sugars from carbon dioxide. The host then digests its own endosymbionts to survive. The evolutionary result of this complete dependence is a no-frills organism that is reduced to only the essentials. Over time, Olavius algarvensis has lost all of the structures related to a normal munching and crunching lifestyle: namely its mouth, gut, anus, and even its nephridia, which function like kidneys. The worm’s nitrogenous waste that would normally be excreted as ammonia is instead recycled by the bacteria and used to fuel further metabolism. In this case, the adage ‘use it or lose it’ most certainly rings true. Evolutionary outsourcing can lead to not just the loss of biochemical pathways, but the loss of entire organs in extreme cases.

*Wigglesworthia is the best bacterial genus name I have heard in ages

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Garden of Deceit

An alpine meadow. Lurking among the flowers are 'pseudoflowers' that are involuntarily formed by plants infected by a pathogenic fungus. Photo source: Wikipedia.

An alpine meadow. Lurking among the flowers are ‘pseudoflowers’ that are involuntarily formed by plants infected by a pathogenic fungus. Photo source: Wikipedia.

It’s an idyllic summer scene in the Canadian Rockies: silent snow-capped peaks watching over bumblebees haphazardly buzzing to and fro over an alpine meadow strewn with bright yellow buttercups. A closer look at this garden of golden blossoms reveals imposters among the familiar cheerful buttercups. Here and there are plants with dense clusters of leaves that seem almost as if they have been dipped in a sticky, granular yellow substance. These ‘pseudoflowers’ are not the work of some hermit with a strange sense of humour and a paintbrush, but are an elaborate deception staged by a fungus to con bumblebees into doing its bidding.

The fungal swindler is Puccinia monoica, a rust disease infecting both grasses and members of the mustard plant family. It is driven to a life of deceit by the fact it is a heterothallic fungus, meaning it has a genetic mechanism preventing it from successfully breeding with itself or close relatives. With no ability to move around on its own, this rust fungus must rely on insects to carry its propagules to different plants in the hopes of a random encounter with a compatible mate so it can complete its life cyle. Puccinia monoica’s life cycle is complex, and the fungus shifts hosts throught the season. During the spring, the fungus inhabits Drummond’s rockcress (Boechera stricta), but by late summer the fungus must shift to live on its grass host, where it can produce resistant propagules called teliospores that either infect new rockcress plants, or survive the harsh mountain winter in the soil. Those individuals that infect rockress plants in the fall, settle into the plant’s growing tissues to wait out the winter.

The rust fungus Puccinia monoica goes to elaborate lengths to dupe bumblebees into transporting its spores around. To the right, a graceful buttercup, and to the left, a pseudoflower caused by the fungal infection that mimics the buttercup and attracts its pollinators. Photo sources: Wikipedia and Cano et al. 2013.

The rust fungus Puccinia monoica goes to elaborate lengths to dupe bumblebees into transporting its spores around. To the right, a graceful buttercup, and to the left, a pseudoflower caused by the fungal infection that mimics the buttercup and attracts its pollinators. Photo sources: Wikipedia and Cano et al. 2013.

Come spring it is time to perpetrate the con, and Puccinia monoica begins to manipulate its host. The fungus conducts a symphony of gene expression to create the perfect vehicle for its ruse: encouraging stem growth, suppressing branch formation, halting flower production, and increasing sugar transport, causing the plant to weep sugary nectar from much of its surface. Some 250 biological processes are affected in the plant as the fungus molds it to its purpose. The ultimate results? The rockcress forgoes forming its own rather drab flowers that are of limited interest to pollinators and instead produces showy yellow pseudoflowers: long stems topped by dense clusters of leaves that become covered in bright yellow fungal rust pustules and drip a sugary nectar mimic. The fungus’ timing is perfect, and the pseudoflowers appear just as the surrounding graceful buttercups (Ranunculus inamoenus) begin to flower, creating an alpine garden buffet for pollinators. So complete is the deception that the pseudoflowers even produce a distinctly sweet scent and fluoresce under UV light in the same way true buttercups do. The pseudoflowers are an irresistible lure to bees, which visit pseudoflowers both longer and more often than co-occurring true flowers. These visiting bees become covered in spermatia, a type of fungal spore, which they then move around the sticky surface of the pseudoflower as well as to new pseudoflowers, allowing Puccinia to find a genetically compatible mate. For the fungus, it is mission accomplished. Its life cycle continues, and its deception has been successful.

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Invertebrate Insecurities

An African Giant Millipede

Millipedes have a variety of chemical and physical defence systems to protect themselves from predators, some of which are more impressive than others. Photo available here.

You can’t find my file? It’s Milton Millipede – two L’s. What’s that you say? Make myself comfortable? It’s hard to be comfortable lying here on this couch – my mother always told me if she caught any of my four hundred feet on the furniture there would be hell to pay.

Oedipus complex? No Doc, that’s not why I came. Truth is, I almost didn’t come to your office. It’s getting harder and harder to convince myself to crawl out from under the rock every day and get out into the forest to forage. I just keep thinking that it could all be over in a second. Ants, spiders, lizards, frogs, birds, shrews; the forest is full of things that want to eat me. I mean it’s really not safe out there, Doc. On Monday night, I was just minding my own business looking for some nice leaf litter to chew on and I get this feeling like I’m being watched. So I circle back a little and there’s this little punk assassin bug hiding under a fallen leaf. He was following me! Do you have any idea how deadly those things are? They just jump out of nowhere onto your back and jab you with that proboscis. Then you’ve got just enough time to realize what has happened before the enzymes and venom they’ve injected you with turn your insides into liquid for them to slurp out at their leisure. I was lucky there was a rock to scuttle under where he couldn’t get at me. Just thinking about how close I was to becoming a millipede milkshake gives me the heebie-jeebies. That’s the problem, Doc, I’m getting too scared to go out. I’ve got to go out to eat, but the forest just isn’t safe.

Millipedes often have bright, aposematic colouring that acts as a warning system for predators indicating the millipedes have other chemical defence systems. Photo by Luis Alejandro Bernal Romero.

Millipedes often have bright, aposematic colouring that acts as a warning system for predators indicating the millipedes have other chemical defence systems. Photo by: Luis Alejandro Bernal Romero.

It just feels like I got the evolutionary short-end of the stick in the family. I’ve got this second-cousin in Europe and he makes this stuff called glomerin. It’s some quinazolinone based sedative that can knock out a wolf spider for days. And one of my aunts, she’s gorgeous AND deadly. She’s one of those flashy aposematic species, all red and black stripes that spell out ‘danger’ to any animal with colour vision. If an assassin bug or a bird or a shrew comes anywhere near her? BAM. She nails them with hydrogen cyanide from these nifty little repugnatorial glands on her back. The stuff doesn’t seem to phase her at all, but it does a number on whatever is trying to eat her. Even if one of them does eventually get her in the end, at least she’s taking them down with her: I hear she can make enough of that stuff to kill a pigeon. When I was a larva, my mom used to tell me stories about these distant African relations we have that spray quinones so strong that they can blister skin. I’d feel a lot more secure if I was walking around knowing that a little squirt in the face from me would have all the mammals and amphibians crying, “Make the burning stop!!”

Focus on my own strengths and positive attributes? It’s tough to be positive when you’re in a family full of folks with bad-ass defense mechanisms and you’re the lowly guy that just smells too bad to eat. Sure, ants run the other direction when they see me coming, so I’ve got no troubles there, but so do most of the mammals in the neighbourhood and it sure doesn’t make me feel like I’m winning any popularity contests in the forest. To make matters worse, I’ve heard there are some birds in the area that have started using millipedes to keep the ants and mosquitoes away. Every time a shadow goes over, I get a full fledged panic attack because the only thing worse than getting your guts sucked out by an assassin bug would be getting speared by a woodcreeper, rubbed all over its feathers like roll-on bug-spray and then eaten whole. Not a dignified way to die.

Try curling up into a ball and staying still when there’s a bird around? Hey that’s not a bad idea, Doc. Lay low ‘till the thing flies over. Even if one does notice me, this exoskeleton I’m carrying around is calcium-reinforced chitin. It’s way tougher than the average insect exoskeleton, and no bird wants to chip a beak over a snack-sized morsel like me.

It’s been an hour already? Ok. Thanks, Doc. Same time next week? I’ll try out that ‘safe position’ with the birds, and if I don’t show up, you know it failed. Think positive? Right, positive. Stand strong, get out there, and shred it. It’s another night, and there’s a forest full of leaf litter with my name on it, just waiting to be eaten. Here goes!

Interested in a more in-depth scientific discussion of defense mechanisms in millipedes? Check out this review paper.

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Full-on Fulmar Invasion

A zodiac departing a research vessel in Engelsbukta on Svalbard. Photo by Marie L. Davey.

A zodiac departing a research vessel in Engelsbukta on Svalbard. Photo by Marie L. Davey.

The fjord is glassy, an impossible shade of blue-green, reflecting mountains and puffy clouds back at a blue arctic sky. I am on an arctic research expedition in the Svalbard archipelago, and our zodiac is tracing a rapidly disappearing white trail across the water. Students and teachers alike are reclining in the warmth of the polar summer’s sunshine, lost in thought, as the steady drone of the engine makes conversation impossible. A light touch on my arm breaks my reverie as a student signals the arrival of our near constant companions on the water: a group of fulmar (Fulmarus glacialis). They arrive silently and without fanfare, lithesome grey shadows appearing as if by magic in the air all around the boat. On wings held stiff and steady, they glide for seemingly impossible lengths of time bare centimeters above the wake of the boat, jockeying with one another for the best position behind us.

The northern fulmar (Fulmarus glacialis) has a distinct, stiff winged flight and is a surface-feeding sea bird. Photo by Marcel Holyoak

The northern fulmar (Fulmarus glacialis) has a distinct, stiff winged flight and is a surface-feeding sea bird. Photo by Marcel Holyoak

In such a remote place, the familiarity is a comfort, and sighting these birds each time we take to the water has become like welcoming old friends for a visit. I find it striking to think that the Norwegian, Dutch, and British men who combed these seas searching for whales as early as the 17th century would not have had the constant companionship of fulmar gliding around their ships. Archaeological evidence and written records indicate that, until recently, fulmars had a limited distribution and bred only on Iceland and the St. Kilda archipelago in the outer Hebrides off the coast of Scotland. But in recent years, new colonies have been founded all over the arctic, including Svalbard, and the number of fulmars has exploded so the global population now pushes 20 million.

Fulmar chicks are little balls of fluff that pack a deadly punch. The oils in fulmar vomit can strip the protective coatings from other bird's feathers, making them susceptible to the elements. Photo available here.

Fulmar chicks are little balls of fluff that pack a deadly punch. The oils in fulmar vomit can strip the protective coatings from other bird’s feathers, making them susceptible to the elements. Photo available here.

What is the secret of the fulmar’s success? My Darwinian side would like to think that the fulmar’s unprecedented expansion is an example of some evolutionary adaptation allowing the fulmar to flourish in conditions too challenging for other birds. It doesn’t seem so far fetched, considering that fulmars have specialized cephalic ‘salt’ glands that allow them to drink sea water in amounts that would kill most mammals. Located above the bird’s nasal passage, these salt glands excrete a highly concentrated solution of sodium chloride, allowing fulmars to maintain more moderate salt concentrations in their cells. However, salt glands are common among marine birds, so they can’t possibly explain the fulmar’s sudden expansion across the northern hemisphere. Like any Darwin-enthusiast, I’m also a fan of a good inter-species fight and I had hopes that the fulmar’s success came as a result of some physiological or behavioral trait that knocked out the competition. Indeed, the fulmar’s e self-defense abilities are renowned, for both their efficacy and gag-inducing smell. Even as chicks, fulmars can projectile vomit a greasy mess of stomach oils on any threatening predator that strays too close. If the unlucky vomit recipient happens to be a predatory bird, the outlook is grim. Extensive testing has demonstrated that fulmar stomach oils strip the natural protective coating from the feathers of other seabirds. Without this protective covering, the birds easily become waterlogged. It can take more than 3 weeks for the fulmar stomach oils to disperse and the feathers to regain their protective coating, meaning that most recipients of a fulmar fouling become sodden and water logged, and die of exposure within days of the attack. However, fulmar are not aggressive pukers, and relatively few birds in natural systems are reported to fall victim to fulmar ‘fowl play’ each year. It seems unlikely that the fulmar’s prodigious territorial expansion is the result of acts of regurgitation warfare on other birds.

Despite the fulmar’s amazing adaptations to a life at sea and its effective, albeit unorthodox, ability to hold its own in a fight, the real explanation for its expanding population likely has nothing at all to do with evolution. Instead human influences seem to have tipped the scales in favour of the fulmar. With the rise of large-scale commercial fisheries, there have been increasing numbers of fishing boats plying coastal and deep ocean waters, and the offal and garbage released from these boats at the surface of the ocean is the equivalent of an all-you-can eat gourmet buffet for fulmars and other surface feeding sea birds. In addition, changing ocean conditions potentially linked to climate change and pollution have altered the abundance and distribution patterns of the copepods, jellyfish, and squid that normally make up the fulmar’s diet. An abundance of nutritious food in the right places has driven subsequent population increases and range expansion, to the degree that fulmar colonies are now found throughout the north Atlantic, from the east coast of Canada to Russia to the far reaches of Svalbard and Greenland.

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