Her own research and collaborative spirit continue to push the boundaries of forensic entomology. In a paper published in June 2023 in the scientific journal Insects, she and her co-authors outlined protocols for best practices in bug-based crime-solving—for example, routinely obtaining temperature readings from meteorological stations near crime scenes, to accurately factor weather considerations into analyses, and inspecting soil surrounding a corpse for insects rather than strictly on the body itself. In another study, also published in Insects, in July, she and her colleagues wrapped cotton and other common fabrics around 99 stillborn piglets, to simulate human remains, and examined how blowflies, carrion beetles and other unsavory beings ate through the clothing over several weeks. The results showed that bugs can modify existing cuts and tears in fabric or even introduce new cuts and tears that investigators could easily assume are caused by bullets or knives; the paper illustrated how easily police and medical examiners might be led astray by assumptions about analyses that don’t incorporate cutting-edge research about bugs. And in September, she was a co-author of another study, published in the journal Forensic Sciences and produced in cooperation with police in India, that showed how studying ant activity and resultant bloodstain patterns can provide clues about the circumstances surrounding a person’s death, including whether the body has been moved.

Fredrik Sjöberg | The Fly Trap | Pantheon | translated from the Swedish by Thomas Teal | June 2015 | 12 minutes (3,476 words)

Below is an excerpt from The Fly Trap, by Fredrik Sjöberg, as recommended by Longreads contributing editor Dana Snitzky. 

* * *

The German-American psychoanalyst Werner Muensterberger has pointed out that many collectors collect to escape the dreadful depressions that constantly pursue them. He takes up the question in his study of the Holy Roman Emperor Rudolf II (1552–1612), one of the greatest of the truly obsessive collectors, and I’m happy to grant his point, at least if we’re talking about art or books or other objects that change hands in the marketplace and are more or less difficult to find. People who collect everything, as long as it’s curious enough, are especially likely to be engaged in a form of fetishism that does indeed allay anxiety.

I know, for I was once on the verge of buying a house in Ydre solely because a dilapidated outhouse on the property was said to have belonged to the once famous poet and bishop Esaias Tegnér (1782–1846).

Natural objects, on the other hand, are not fetishes in the same way. One reason is that they can seldom be purchased for money. In addition, they almost always lack cultural provenance. Any beetle whatsoever that was caught, pinned and classified by, say, Charles Darwin, would be a wonderful fetish with which to cure a depression, but such things are impossible to come by. It’s true that I own a stuffed peacock whose history is known, including a list of everyone who’s owned it since it died in the nineteenth century, and any desperate character who came along might buy it. But the normal thing these days is that nature collectors catch the creatures themselves. That’s different from dealing in art.

I have a distinct feeling that Freudians in general have a much too diffuse picture of the passions that may express themselves in, say, fly-hunting. They are way too locked in to their squalid little standard explanations of human behaviour. Thus the aforementioned Muensterberger comes to the conclusion that your average collector represents an “anal type” who, if I understand the thing correctly, becomes a collector because in his childhood he was not given sufficient time to play with his excrement. It’s breathtaking. Not even my good friend the surrealist poet really fits in that package.

I run into him occasionally at Entomological Society meetings. An odd fellow, certainly, but no worse than the others. I like him a lot, partly because his utterly incomprehensible poems make my own books look like wonders of clarity and logic, partly because in addition to his writings he guards a position as one of northern Europe’s most distinguished experts on the range and habits of dung beetles. He was out here on the island a couple of years ago, collecting. Freudians would have gone into ecstasies if they could have seen us strolling through meadows, poking at sheep shit or hunkering down beside a fairly fresh pile of horse manure for a professional assessment. No, these are things they just don’t understand.

That I take the trouble to bring up Werner Muensterberger is because he is not always wrong. On the contrary, I think he finds his way through the mist with frightening accuracy when he writes in his book on the psychology of collecting that one thing most collectors have in common is a fairly pronounced narcissism. Well, what can I say? If nothing else, he deserves our attention for supporting his thesis with a touching little story about one of his most interesting cases, a man who falls into the unusual category of “one-object collectors.”

This man collects only a single article.

One objection is, of course, that one article cannot very well constitute a collection. But the man is special in the sense that he displays many of the manic collector’s tragicomic characteristics. He is constantly in search of a better, finer, single specimen, and when he has found it, he immediately gets rid of the old one. One object, neither more nor less. And what drives him is a compelling, intense desire to be seen and acknowledged for his exquisite taste, his mastery. The object, and vice versa—the narcissistic collector in his most crystalline form.

This is perhaps an option for an art collector with a small flat. But collecting a single fly? I don’t think so.

But if you did, it would have to be the narcissus fly, Merodon equestris. A highly varied species, somewhat like the Adam-and-Eve among orchids, though with more colours than just two. On top of which it’s one of those hoverflies that buzzes in such a distinctive way that you can recognize it with your eyes shut, which produces a particularly restful sense of well-being.

Not that I’m in the habit of wandering around outdoors with a blindfold, but it sometimes happens that I need to rest my overexerted, fly-spying eyes for a spell and just stare at the clouds, or at nothing, lying on my back in the grass and moss on the granite slopes. And to hear the quite singular buzz of a passing narcissus fly in the course of such a summer nap is a pleasure, for the simple reason that knowledge is pleasing.

I know this stuff. No one knows more about the flies on this island than I do. The mere sound can be like recognizing someone you know in the crowd on a railway platform. A friend who tells a story, as if in passing, about the yearning of people long since dead for beauty, for the fragrance of an evening in late May when the air is still.

* * *

As early as the Middle Ages there were people in our country who were happy enough and rich enough to import narcissus bulbs from distant southern lands. Narcissus poeticus, the Easter lily, and other bulbous plants in beautiful and ugly colours began then to bloom in garden beds and parks across wide areas of the country, but oddly enough it was only in the 1910s that the narcissus fly arrived. The man who first spotted it, outside Helsingborg, was a still unknown elementary schoolteacher named Oscar Ringdahl. He told the world about his find with a short notice in Entomologisk Tidskrift. The year was 1911. He was twenty-six years old. The rest is history, at least for entomologists.

Oscar Ringdahl became a great man, something of a legend. They called him Fly Ringdahl.

As a youth he began collecting beetles and butterflies and did it with such energy that on one occasion, in pursuit of an attractive beetle, he crawled right under a bench where a pair of lovers sat kissing. But he quickly decided that flies were more fun than other insects, possibly because so little was written about them. He had only a book from 1866 about the people and natural history of Finland in which there was anything about flies. Then he read a work in Latin by Zetterstedt. With these two antiquated books in his baggage, he set out on a hunt for flies that lasted his entire life.

As a brief biography, that’s not half bad. The quotation is taken from a 1944 issue of the weekly magazine Idun and is as good a testament as any to his fame. The article also mentions his wife, Anna, an obviously understanding woman. “ ‘Oscar gets so excited every spring when the flies start buzzing. It makes him forget all the aches and pains of winter,’ says Mrs. Ringdahl, and her husband laughs.” By that time (he had a long life) his collection already contained 60,000 flies.

The larvae of the narcissus fly live in the bulb itself, underground, and they probably established themselves in Sweden by stealing a ride in bulbs being sent from Holland. No one knows for sure, of course, but my guess is that’s how it happened. One clue is that the famous fly expert George Henry Verrall writes in his 1901 book about the hoverflies of the British Isles how, on 8 June 1869, he caught the very first English specimens of this fly in his brother’s garden on Denmark Hill in south London, which received annual shipments of Dutch narcissus bulbs.

The narcissus fly is now common both in England and here in Sweden, even though the various species of the genus Merodon are native to the warmer climate of the Mediterranean. Or were. Now they’re native here too. This fly may have come as an immigrant from the south a long time ago, but now it has the same residency rights as any other fly. This is my basic political position. Not a very risky one, I have to admit, but that’s only because fly politics have never really caught on. Why, I don’t know. Spanish snails, mink, wild boar, cormorants, what have you—they all attract a steady stream of populist xenophobes and loudmouths of every kind, but no one cares about flies. Not even the paranoids keep me company. But it is political. And in fly questions I am a liberal and do not insist on a closely regulated transition period before they can be incorporated into our fauna. Let them come. We’ve got plenty of room.

The question of alien species is quite complex and sensitive. I don’t intend to go into it deeply. But I would like to note that the hoverfly-hunter can hardly be anything but tolerant in the matter of alien species because he spends his time in the border country, literally, between culture and nature, in a microworld governed by constant coincidence and incessant disturbance. Everything is changing, all the time. I am drawn to gardens—and to meadows, the few that are left. For me, they are wilder and richer and much more fun than nature undisturbed by human beings. And so are pastures, avenues, churchyards, roadside ditches and, in the woods, the abruptly clear-cut galleries for power lines. That’s where you find flies! Untouched nature has its merits, certainly, but it rarely measures up to lands that people have disturbed.

Almost any disturbance at all can create a whole new environment, which may sometimes meet the rather intricate demands that some insignificant fly makes on life. It can be quite simple. Let’s say that a young landscape architect falls in love with a girl who says she adores the heavy fragrance of balsam poplar, whereupon he, of course, has an entire forest of balsam poplar planted, perhaps at a university that hires him to design its landscaping just at the time he’s falling in love, and at night these woods come to be used as a meeting place by, say, the semisecret Students for the Liberation of White Russia, who put up completely unreadable posters about their hopeless struggle on the smooth trunks of the fast-growing poplars, using the only tool their organization has a plentiful supply of—namely, White Russian thumbtacks, which contain indeterminable metallic impurities that give rise to a rare form of rot in the tree’s inner bark that some even rarer hoverfly’s sap-eating larvae require in order to survive to adulthood.

Even more wondrous is how these flies find the trees to begin with. I suspect that they have spies out circulating everywhere.

I particularly want to emphasize the importance of love in this context. All too often, love is the unappreciated factor in the development of the culturally determined ecosystems that today harbour the richest menageries of hoverflies. Historically, it was probably the privations of poverty that led people to shape the landscape in ways favourable to flies, but today that landscape is shaped more by wealth and desire. Gardens are the best example. Now that there are no more farmers on the island, it is in gardens we find the greatest wealth of fauna.

* * *

I don’t know if the Russians brought any new plants or animals when they laid waste to the island and burned the houses in 1719, but suspicion of strangers from the east has never completely lost its grip on the residents. The fact that a one-year-old great cormorant caught in a fisherman’s net had been banded in Murmansk did nothing to improve the cormorant’s already dubious reputation, and if more people knew what the narcissus fly’s offspring were so diligently up to in the guts of the flower bulbs, I can imagine that it too would incur the wrath of gardeners and provoke clumsy attempts at eradication.

On the other hand, no one has touched the oddity at Silver Lake. Even though it comes from the New World.

It was one of my first years out here, at a time when, like the man who loved islands, I was devoting my summers to compiling a catalogue of all the island’s plants. One day I walked out to Silver Lake to have another look at it and to smell the smells I’d smelled before. The lake itself is a bottomless pool, as black as the lakes in John Bauer’s wash drawings, and it lies in the midst of a quagmire in the middle of the island in the deepest woods, where people have never lived. There are eight other lakes on my island, all of them larger, their shores lined with cottages, flagpoles and peeling rowing boats asleep among the alder saplings, reeds and loosestrife. Only Silver Lake lies off the beaten track. And nothing is more stable than a quagmire.

How hard it is to find the place, and then find your way home again, is something even Strindberg had to learn. He borrowed the name of the lake for a bitter short story about his loneliness and distress after his divorce from Siri von Essen. She and the children were with him on the island that first summer, then never again. His protagonist, a museum curator, sets out for the lake to fish but gets lost, and although he is an enlightened man who carries the natural sciences like a cast-iron defence against the dark powers, he soon finds himself entangled in a formless struggle with capricious malevolence. “He recognizes every sound and knows every plant and animal, so if he heard or saw anything strange, he would consider it impermissible.”

I wonder what would have happened if he’d caught sight of what I saw in the sucking peat moss right at the edge of the lake. An American purple pitcher plant. For a moment, nothing was heard but the rustle of a dragonfly’s wings.

An alien, carnivorous plant, several feet tall, as imposing as if it had come straight from John Wyndham’s classic thriller The Day of the Triffids. Just one lonely, magnificent plant. How it got there no one knows, and I can assure you that there’s no truth to the rumour, widespread among botanists, that I put it there myself. It’s true that it could have been me, but it wasn’t. Which hasn’t kept me from entertaining very warm feelings for the purple pitcher ever since that day, not because it catches flies in its fluid-filled leaf cups, or because it’s so rare, but rather because, in the manner of naturalized intruders, it breaks a pattern and astounds. Biological xenophobia is widespread but almost always unwarranted.

A little havoc, if only in the form of a garden, seldom does any harm. It goes awry only when the scale gets too large. That was one of the few things that travel taught me.

* * *

Tropical rain forest is at its best on television. Of course it sometimes happens that the jungle is both beautiful and enjoyable in real life, up close, but believe me, it is more often a kind of disgusting orgy where everything pierces and bites and your clothes stick to your body like cling film. You see nothing of the sun because rank foliage arches over the trail like a musty cellar ceiling and torrential rains turn the path to a slippery drainage ditch where only blood-sucking leeches can get a foothold. You are attacked by malaria-infected mosquitoes, and the mere thought of snakebite and broken bones and dysentery sinks your spirits like a stone, since the distance to the nearest road begins to be measured in days, as is often the case in the tropics. Visitors from northern lands, initially so headstrong and adventurous, stand in the dusk on the sodden, rotting floor of the rain forest, downhearted, drained, and speak of nothing but the consistency of their excrement and, beyond that, manage to think only very short thoughts. Get me out of here. Get me a beer.

But you couldn’t write about that, not in the early ’80s when all the miseries between the Tropics of Cancer and Capricorn were measured, ridiculously, in units of football-fields-clear-cut-per-second. And if I nevertheless ventured to say something to the effect that Central Africa might benefit from some motorways and pulp mills, people dismissed it as my way of being provocative, which it was not, or else they said that I was just trying to get attention, which wasn’t true either, except maybe a little.

Narcissus poeticus spreads its fragrance in the spring evening. Narcissus flies sing in the undergrowth like tuning forks. The high-frequency hum of their wings is like a footnote that makes the experience all the richer for those who know the sound.

* * *

The last thing I needed was a house in Ydre, especially not in Svinhult, but that’s where it was, walking distance from nowhere in Småland.

I saw the ad by chance. Late-seventeenth-century log house in need of renovation. The lot was large and the price so ridiculously low that my imagination, which needed somewhere to live that day, occupied the place from the moment I saw the ad and sank in its jaws just long enough for curiosity to begin morphing into a desire to possess. The house was really cheap. If it had been on the island, the price would have been twenty times higher, at least. I called the broker, in Tranås, but he knew very little and explained that at that price he wasn’t interested in doing much more than running the ad. He referred all questions to the seller.

This proved to be an old gentleman, slightly confused, who lived somewhere out in the woods. He chatted with me long and well, clearly both pleased and surprised that someone had an interest in his hovel. I listened, guardedly, moderately eager to own this ruin at the end of beyond. Troubles you can have for nothing, I thought. Why buy more of them in Svinhult? It was then he said the thing about the outhouse—parenthetically, no big deal, a curiosity perhaps, nothing more. It had belonged to Esaias Tegnér. Then he said that, shortly after Tegnér’s death in 1846, an auction was held at Östrabo in Växjö to sell the contents of his house. Even the outhouse was auctioned. For many years it had stood behind the parsonage in Svinhult. Now it was his.

Municipal offices in Ydre confirmed the story. The cabin was old and ramshackle, and there was folklore about the outhouse. I was now bewitched. I called Professor Bergh in Lund, chairman of the Tegnér Society, and he couldn’t get a word in edgewise as I poured out my questions about the property auction. He hemmed and hawed for a while in confusion, then gave me an experienced assessment of my chances of establishing a provenance for the rotting outhouse. They were small. He himself had never heard of the object, but there was another individual in the society I might speak to. She was an archivist of the old school. If there was anything at all about the outhouse in writing, she would find it if anyone could. I called her. Heard how she slowly shook her head. My pulse resumed its normal rhythm.

Three days later she called me back. It sounded as if she had run to the phone, for she was a little out of breath when she asked me if the outhouse in Svinhult was a two-seater.

“A two-seater it is,” I said.

“There was a two-seater sold after Tegnér died,” she said.

There was bidding on the house, and I hung in there a good bit beyond the starting price. The broker was in Tranås with a telephone in each hand. On the one, me; on the other, a bidder from Mariannelund. He got the place for 73,000 crowns. I’ve never had any regrets. But it was only afterwards that I asked myself what I actually wanted with that house. About the point of the whole thing. The only answer I could come up with was that I had been carried away on a wave of irresistible desire to collect that outhouse. Like a fetish.

“Hi, everyone, I’ve travelled around the world and I own Tegnér’s crapper.”

No, it wouldn’t do. Flies are better. They allay anxiety in a different way. On top of which they’re free.

* * *

From the Book: THE FLY TRAP by Fredrik Sjöberg. Work © Fredrik Sjöberg. English-language translation © Thomas Teal. Published by arrangement with Pantheon Books, an imprint of The Knopf Doubleday Publishing Group, a division of Random House LLC