On meadows, in bushes, under water and up trees – nature is seething with desire.
In one of his poems, Alfred, Lord Tennyson wrote of nature that it is “red in tooth and claw”, and this phrase became a popular symbol of the Darwinian fight for survival as the ruthless principle of evolution. I dare not presume what it really is that nature drips with, but – although the vision of bloody animal struggle excites the imagination – its role can be overestimated. Constant battle is less important in the natural world than love. Not necessarily lyrical love – very much the bodily kind. Or, to put it bluntly, sex.
Of course, combat and love interweave throughout nature. As another saying goes, all is fair in love and war. However, the latter is more frequently in service of the former than the other way around. Animals and plants often fight for partners, but even the strongest fighter won’t get very far in the evolutionary conflict if it can’t pass on its warrior’s genes. This conditions most animal behaviour, directly or indirectly. The aim is that copies of our genes – even if they don’t come directly from us, but from our close relatives – must survive and multiply in the gene pool of future generations.
Somebody pollinate me!
I have never been to a biology lab, on any continent, that didn’t have at least one Gary Larson drawing on the wall. Naturalists love him; he’s a biology graduate with a unique sense of humour who wrote a children’s book that I still consider to be the best introduction into the functioning of ecosystems: There’s a Hair in My Dirt! The book tells the story of a family of earthworms. While at dinner (of course, the characters are eating dirt, as earthworms would), a disgusted son loudly announces his revolting discovery. Dad earthworm then explains how a long blond hair would have found its way into their soil, at the same time giving a concise and engaging explanation of the flow of matter and many other natural phenomena. For now, however, the most important fragment for us is the one in which Harriet – the former owner of the hair – admires a flower-filled meadow and calls Mother Nature a wonderful artist. The storytelling dad corrects her, saying that Nature should really be called a sex maniac: a flowering meadow is, in fact, a “reproductive battlefield”, while plants make use of “bright colours, nectar, mimicry, deception” and many other tricks to attract the attention of the pollinators.
Indeed, plant pollination by animals is common in nature. It’s one of the most widespread forms of mutualism, a kind of interaction between two species that benefits both sides. From what we know, this practice has been going on for over 100 million years, and it involves almost 170,000 species of plants (which is about three quarters of all flowering plants), and around 200,000 animal species. The pollinators are, of course, mainly insects: bees, butterflies, moths, flies, wasps and beetles, but there is also strong representation from birds, bats, and even lizards.
The simple act of transferring pollen from the stamen to the pistil, which forms the basis of plant sex (hence, to encourage genetic diversity, it’s best if the stamen and pistils are on separate plants), usually involves a reward for the pollinator. That reward is sweet nectar, which plants advertise more or less honestly to the interested parties. Sometimes the pollinators’ payment also takes the form of safe shelter, where they themselves can reproduce: this way their sexual activity mixes with that of the plants’. Such ‘inter-kingdom’ orgies of plants and animals take place, for example, in figs. Every fruit is home to tiny Hymenoptera (known as fig wasps), which pollinate the flowers of the fig tree in exchange for a safe and nutritious nest. Technically, then, figs are not vegan, because they always contain a few tiny bodies of insects that succumbed to the deceptive promise of eternal happiness.
Tempters, lechers, scammers
Attracting pollinators is frequently a much more interesting process than just offering them delicious nectar wrapped in pretty flowers. After all, not every insect goes in for that. There is a whole group of plants – with the charming name of ‘carrion plants’ – that exude the smell of rotting meat, exceptionally attractive to flies, carrion-eating beetles and Hymenoptera. It contains such oddities as the titan arum, whose Latin name, Amorphophallus titanum, is a better reflection of the shape of its inflorescence, which is the largest in the world and can reach over three metres; or the Rafflesia arnoldii, with its largest individual flower measuring about a metre across.
A stinking reward is better than none at all, which is the situation with orchids. It is estimated that around one third of their numerous and diverse species scam potential pollinators. While it is true that other flowers also sometimes only pretend to contain nectar or edible pollen (tempting with smells and colours), the swindles of some orchids really are of a higher order. Orchid flowers, or parts of their flowers, look – and sometimes even smell – like females of specific insect species. This is how the mirror orchid (Ophrys speculum), which grows in the Mediterranean region, deceives the males of a wasp called Dasyscolia ciliata. Pollination takes place via so-called pseudocopulation, when a frisky male pounces upon the petal puppet in amorous frenzy, but despite energetic attempts he doesn’t pass on his genes – unlike the devious orchid.
But really, he should be happy, because he’s not had the worst of it. Some fungi also exploit the urges of male insects (although in their case it’s not about pollination, but the transport of spores); unlike plants, fungi make their bait from dead, mummified fellow insects – those who let themselves be tempted soon share their fate.
Still, although the world of plants and fungi has plenty of sophisticated tricks at its disposal, true debauchery is the domain of animals – even those that seem completely innocent.
Almost 10 years ago, in the archives of the Natural History Museum at Tring in the UK, a four-page pamphlet was discovered; it was stamped with the words ‘Not for publication’. The pamphlet is entitled Sexual habits of the Adélie penguin and it was printed in 1915, but never put into circulation. Its author was George Murray Levick, a member of the British Arctic expedition of the ship Terra Nova (1910–1913) – the one during which Robert Falcon Scott, along with four of his companions, died in dramatic and senseless circumstances. Levick, a physician and zoologist, was particularly interested in the penguins he had observed for a few months at the world’s largest colony of Adélie penguins, Cape Adare. Most of his observations had been published in the expedition’s official reports, and they belong to the canon of our knowledge, but others led him to make this observation in the censored pamphlet: “There seems to be no crime too low for these Penguins.”
The shocked scientist observed a whole range of what he calls ‘hooligan’ behaviour from the males: from homosexual intercourse, through rape – of both healthy and wounded females, and of juvenile penguins – all the way to necrophilia: copulating with the mummified carcasses of penguins who had died in previous seasons. Even to an objective scholar from the Edwardian era, this was too much. Not only did he refuse to publish his observations, but used a code even in the above-mentioned secret pamphlet, recording some of the juicier descriptions in the Greek alphabet.
It was only almost 100 years later, in 2012, that his observations were widely announced for the first time, and the whole pamphlet, along with modern commentary, was published in Polar Record magazine. In the meantime, we have discovered that the adorable and generally loved Adélie penguins (I’ll admit they are my favourite species) have an even wider repertoire of outrageous behaviour, including cheating, divorce and prostitution (females sometimes allow intercourse with males who offer them a pretty pebble, only to use it later to build a nest with someone else). However, in the face of the animal world’s unbelievably low moral standards, penguins are still only, well, the tip of the iceberg.
Although in circles that are resistant to knowledge and decency one can sometimes hear that homosexuality deserves condemnation because it is unnatural, nature itself would evidently beg to differ. According to various interpretations, between 450 and 1500 different animal species display homosexual behaviour. Of course it manifests on a whole spectrum: from innocent caresses, through mutual masturbation and copulation, up to shared rearing of offspring. This is why different researchers’ definitions of animal homosexuality vary. However, irrespective of our definition, this phenomenon is common in nature.
Scientists have long wracked their brains over the so-called Darwinian paradox, because sexual behaviours that don’t lead to reproduction seem to be a waste of time and energy. The crux of the matter is that nobody can estimate these costs and they needn’t be high at all. Still the question remains: Why do animals do this? Why have such unproductive sex? It turns out the reason is exactly the same as with the productive kind: because it’s pleasurable. Evolution has invented sex in order to mix genetic material, which is vital for organisms to improve their characteristics and to cope in a mutable environment. However, unlike all other basic needs, the sexual urge provides palpable benefits only after some time has passed. If hungry, an animal will eat and is hungry no longer; the same applies to thirst. But there’s a delay to the results of gene mixing, frequently of many weeks or even months. So if sex wasn’t simply pleasurable, who would want to bother?
Of course, this is something of a simplification. There’s a whole range of sexual behaviours, and explanations may vary on a case-by-case basis. However, if we assume that sexual preference is not a binary issue (either this or that), but that it forms a wide spectrum between two extremes, it is easier to understand why so many animals – humans included – get involved in non-obvious arrangements.
The benefits of homosexual sex can, in fact, be manifold, sometimes strictly within the context of heterosexual relations. Male chimpanzees, for example – especially young ones – commonly engage in copulation with other males, which, apart from pleasure, provides them with practice for the future. In hierarchical chimpanzee communities, the alpha males exercise strict control over access to females, so if other males want to have a hope of success at the rare opportunities when they can surreptitiously meet their chosen one, it’s important that they know exactly what to do.
In the case of walruses, too, homosexual behaviour is not so much an issue of permanent preference as of the availability of partners. Most young males enthusiastically dabble in various homosexual delights for the first few years of their life, until they’re sufficiently grown to fight for females in the next breeding season. Groups of males cuddle and sleep together, engage in mutual masturbation and copulate. Later, as adults, they turn bisexual and are interested in females during the breeding season, but outside it they return to the joys to be found in the embrace of other males. It’s worth noting that this is facilitated by a penis of considerable size, equipped with a baculum, or a penis bone. Many mammal species have it, but in walruses this bone is the longest, and can reach 60 centimetres! Inuit call it oosik and use it to craft various ceremonial objects and tools; the Russian tsar Peter the Great allegedly even had a stool with four legs made of such specimens. Walruses are generally quite debauched and will also copulate with females of other pinniped (or seal) species – if there is none of their own around at a given time.
Fifty faces of dissolution
In the case of garter snakes – small snakes found in North America – males flirt with other males to dull their vigilance, so that at a decisive moment they can snatch the female, still numb after winter hibernation, for themselves. Scorpionflies act similarly. These insects (which also live in Europe) catch flies, and then present them to females as a nuptial gift that provides them with a stockpile of food necessary for the production of eggs. And, well, some males dress up as ladies so that they can accept the gift and then pass it on. But this isn’t bad at all in comparison with the lechery of bedbugs. These rather unpopular insects engage in something we call ‘traumatic insemination’. The male reproductive organ is something like a dagger which stabs through the surface of the partner’s body, so that sperm is deposited directly into her organism. Sometimes, however, male bedbugs copulate with other males, inserting their sperm into them; the poor wretches then carry it around, and if they’re lucky enough to find a female, they inseminate her with somebody else’s sperm!
Homosexual behaviours and relationships can also have a very practical significance. While homosexual individuals don’t themselves reproduce, in many social species they take care of their relatives’ offspring. This makes sense: this way they contribute to the preservation of family genes. They also frequently rear their own or adopted young. One of the most famous gay couples were Roy and Silo – chinstrap penguins from Central Park Zoo in New York City who brought up a daughter adopted as an egg and called Tango, which became the basis of a beautiful children’s book, Justin Richardson and Peter Parnell’s And Tango Makes Three. Unfortunately, after six years of happiness, in 2005 Silo ditched Roy for a female called Scrappy.
There are a few other same-sex penguin couples known from zoos, but many more relationships like this can be seen in the wild. Among Australian black swans, but also European greylag geese, a quarter of stable relationships are made up of male couples; they either forcibly take over other couples’ nests, or have a short-term fling with a female until she lays eggs, and then successfully rear the young. Laysan albatrosses have an opposite arrangement: it’s the females that form long-term relationships and initiate short-lived love triangles with ‘married’ males, and then rear the chicks within female couples. And it’s not only birds that engage in such relationships – long-term female couples have been observed, for example, in Japanese macaques; they also need males only for reproductive reasons. Short- and long-term homosexual relationships have also been noted in many dolphin species, including killer whales, as well as giraffes, elephants and even lions, who strengthen male alliances in this way.
There’s an interesting principle among primates: the more closely related to humans they are, the more sexual combinations they display. Hence, homosexuality is more frequent in so-called Old World monkeys than in American species (although it has also been observed among spider monkeys). However, our closest relatives, i.e. bonobos (or pygmy chimpanzees), are the real lechers. These hippies of the animal world usually end conflicts and other social situations with copulation or masturbation in all possible variants, including the participation of children, and over half of this activity is of homosexual nature – among both males and females.
Sleeping with the enemy
Love triangles are not necessarily linked with homosexual tendencies. Some lizards, like the southern alligator lizard, simply reach the conclusion that it’s better to act together. In such cases, two males aim to copulate with the same female simultaneously, because this way it’s easier to hold her down. Similar situations also happen regularly among bottlenose dolphins – but there it’s more reminiscent of gang rape.
It’s a bit different with the southern right whale. Like the bonobos, these whales subscribe to the ‘make love, not war’ principle. But – as can be easily imagined – with no hands, and in water, it might be difficult to copulate even with the friendliest, but also rounded and slippery female. Admittedly, the penises of these mammals are long and mobile like boa snakes, but males still regularly give each other a helping fin and take it in turns to hold the female partner for each other, even if they’re complete strangers. Which doesn’t mean there is no competition between them. After all, if we help someone outside of our family, our genes do not benefit. But among the above-mentioned whales, like with many other animal species, the real fight takes place within the female’s body. If more than one male’s sperm ends up there, one of the most fascinating – albeit common – natural processes takes place: sperm competition. This is because evolutionary success is not decided by who copulated with whom, but whose sperm reaches the egg.
Ejaculate, including the human kind, contains sperm of varying shapes and motility. The purpose of some of them is not to race for the Holy Grail, but to block any competition. Although there are many ways to achieve this, most frequently it’s a question of numbers: the more numerous my sperm is, the more likely it is to succeed. This is where the whales’ secret power manifests itself: large numbers of sperm require large testicles, and those of the southern right whale are the biggest in the world. Each testicle weighs up to 500 kilograms (for comparison, the testicles of the world’s largest animal, the blue whale, weigh ‘only’ 30 kilograms). If the vision of sperm wars that entail the creation of barricades in tight spots – or even the active search of enemies and dissolving them in a suicide attack (so-called kamikaze sperm) – seems somewhat terrifying to us, we can be grounded by the realization that with some sharks things are even more serious: embryos created by different fathers seek each other out and eat each other, also while still in the mother’s body.
Removing a rival’s sperm also contributes to success in the competition. This is the reason why many animal penises have various types of spines (like the cat’s) or elaborate shapes. The British zoologist Robin Baker, author of the book Sperm Wars, is even of the opinion that this is why the human penis resembles the shape of the plunger for clearing pipes – it’s supposed to pump out what someone else could have left behind. An alternative for removing a predecessor’s sperm is to physically clog up the female, which is why many species make special plugs, usually created after the ejaculate dries. They enable scientists to count inseminated female bats in dark colonies. Males wake up from hibernation and copulate with the sleeping females, and when they wake up in spring and start moving, the plugs fall to the floor of the cave with a characteristic clatter.
Of course, there are many more sexual variations. Some animals, like snails, have the genitalia of two sexes, and during copulation they simply exchange sperm. Others, like the clownfish (known from Finding Nemo), hatch from eggs as males and turn female as they grow, because in the case of that species it is more profitable to be able to produce more eggs. Certain fish, like the bluehead wrasse, have it the other way around: their competition can be fiercer and it is better for the grown-up fish to be a male that can chase away rivals, so it is females that change sex when they reach the appropriate size.
Real orgies also take place in nature, for example among some marine bristle worms: whole animals, or only their specialized reproductive organs, float to the sea surface on certain nights and copulate energetically on an ‘all you can eat’ basis. The local population calls them ‘palolo worms’ and catches them as a delicacy.
Darker strategies involve rape, regularly perpetrated by both mallard drakes and the males of the seemingly cute and innocent sea otter. It can definitely be said that to nature, absolutely nothing human is alien. And some phenomena from nature’s amorous repertoire have never been dreamt of in our philosophy – or only a very strange one.
Translated from the Polish by Marta Dziurosz