Life
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Suspecting abduction or a child surrogacy scam, the court put Fairchild’s children in foster care and charged her with fraud. A court officer was present to witness the birth of her fourth child, but even that was not persuasive; only DNA would be accepted as evidence of the child’s maternity. Even Fairchild’s father, dazzled by science, began to have doubts about his daughter’s honesty. Thankfully, her lawyer recalled an earlier, similar case that had resulted from chimerism. Through sheer good fortune a hospital had kept a cervical smear taken years earlier, and analysis of the sample revealed that the cells of Fairchild’s body were derived from two genetically distinct female eggs that had fused to form one individual. Her sex cells came from one egg, while the parts of her body used in the DNA test came from the other. The court was finally convinced, and Fairchild’s children were returned to her, but not before severely traumatising the family. As we contemplate the potentially dire consequences of the case, the fact that supposed scientific evidence is so persuasive that eyewitness testimony, and even the love of a parent, could be negated by it should act as a caution.
Chimeras can also result from pregnancy. Cells from embryos regularly cross via the placenta into the mother during gestation, while her cells can end up in the embryo. It is astonishing how long such cells can survive. One woman who had given birth to a son still had cells with Y-chromosomes in her body twenty-seven years later. In another case, an entire lobe of a woman’s liver that had been damaged by disease was repaired by fetal cells that remained in her body after an abortion. A mother’s brain cells, too, can be derived from offspring.
As long as chimeras and mosaics were detected on the basis of physical manifestations or blood type, they were considered to be phenomenally rare—indeed freakish. By 1983, only seventy-five cases of human chimeras, as detected from blood type, were known, while mosaicism was mostly known from medical cases. Joseph Merrick, the ‘Elephant Man’, suffered from a form of mosaicism known as Proteus syndrome, which left parts of his body deformed by monstrous growths, while other parts remained completely normal. For decades, his sad example defined the condition for many.
Recent advances in genetic analysis have revealed that chimerism is common. In fact, chimeric individuals may be the rule, rather than the exception, among mammals. One Danish study of the blood of 154 girls aged ten to fifteen discovered that around thirteen per cent of them had blood cells with Y-chromosomes. These cells probably originated from an older brother and had crossed into the mother, where they survived before crossing into, and taking root in, the daughter. A Seattle study of fifty-nine women who died, on average, in their seventies found that sixty-three per cent had cells with Y-chromosomes in their brains.
As bizarre as chimeras might seem, they represent only the surface waters of Zimmer’s deep dive into the nature of inheritance. Epigenetics, a fast-expanding area of science that explains how things experienced by individuals can influence the traits that are inherited by their offspring, seems to contradict our conventional understanding of genetics. The epigenome, ‘that collection of molecules that envelops our genes and controls what they do’, as Zimmer puts it, operates through methylation—the process whereby methyl-group molecules are added to the molecular envelope surrounding the DNA, and so inhibit certain genes from operating (and, in some cases, from operating in descendants as well).
We owe one of the most penetrating insights into epigenetics to a laboratory accident. Michael Skinner of Washington State University was examining the impact of the anti-fungal agent vinclozolin on laboratory rats. He discovered that the offspring of rats exposed to the chemical produced deformed sperm. When a laboratory assistant accidentally used these offspring to breed a new generation of lab rats, researchers discovered that the grandsons of the poisoned rats also produced deformed sperm.
Skinner’s rats sparked a flurry of new experiments that showed how methylation could lead to the inheritance of acquired traits. As some researchers commented, it was as if the work of Jean-Baptiste Lamarck (who famously posited that the necks of giraffes had lengthened over generations because they were stretched as the animals reached up to feed) had become re-established. Science is rarely so simple—still, epigenetics has Zimmer wondering whether ‘poverty, abuse, and other assaults on parents also impress themselves epigenetically on their children’. The study of epigenetics is still in its infancy, so it may be years before we know the answer. With some recent studies showing that epigenetic effects fade over time, many researchers are unsure whether epigenetics is anything but an interesting codicil to the conventional genetic theory of inheritance.
The recent development of CRISPR-Cas9 technologies has elucidated yet another potential pathway of inheritance. Cas9 is an enzyme produced by the immune systems of bacteria that fights viruses by breaking up their DNA. As it turns out, it also offers a way to use RNA to guide precise editing of a genome by removing or adding genetic sequences to chromosomes. CRISPR-Cas9 could be used to edit out defective genes and even insert new ones. Reporting on CRISPR in 2014, Zimmer realized that he ‘was witnessing the beginning of something enormous’. One of the discoverers of the technique, Jennifer Doudna, was meanwhile having recurring nightmares about her discovery. In one nightmare she found herself on a beach staring directly at an oncoming tsunami. In another she met Hitler, who had the face of a pig. As Doudna spoke, the pig-Hitler jotted down notes.
In one of the first uses of CRISPR-Cas9 for biological control, attempts are being made to modify mosquitoes so that they cannot carry the malaria parasite. But because relatively few mosquitoes bear the inserted genes for malaria resistance, their genetic inheritance is quickly diluted when they are released into the wild. If the inserted genes are to spread, another technology known as a gene drive is required. A gene drive is an additional bit of genetic modification to propagate genes in a population by giving them a greater than fifty per cent chance of being inherited.
As of 2015, results from the mosquito work were mixed, with some female descendants eliminating the gene that had been inserted into their ancestor’s genome using CRISPR. But in 2018, after the publication of Zimmer’s book, researchers announced that they had successfully propagated genes in mosquitoes using a gene drive. With both CRISPR and gene-drive technologies becoming more powerful by the year, we must look to visionaries to comprehend its potential. George Church, a geneticist at Harvard and MIT, believes that CRISPR will inevitably be used to create genetically ‘superior’ humans. Alterations to our genome will creep in the door through the treatment of diseases, he says. Imagine if gene editing can be used to treat wasting muscles, or Alzheimer’s, or to prevent HIV infection (as was allegedly done to a pair of unborn twins recently in China)—how long would it be before those same techniques are used to create super-muscles or super-cognition?
Church is rightly concerned about CRISPR’s potential to permanently alter human gene lines, as are other scientists. Marcy Darnovsky, the executive director of the Center for Genetics and Society, thinks it will lead to an ‘unregulated marketplace’ in which gene editing, which can inflict harm on unborn children, will run rampant. Given the history of earlier misunderstandings of inheritance that Zimmer relates, it’s a warning we better take seriously.
Throwim Way Spices: Adventures in Eastern Indonesia
2019
IN THE KEBUN Raya at Bogor (Indonesia’s national botanic garden, south of Jakarta) I loitered under the shade of a tree that is the last of its kind. The species avoided total extirpation when it was plucked up as a seed, from the great forests that once covered Java like a green blanket. It started life in a world of the tiger and the almost mythical one-horned rhino, but today it grows beside a cobbled path, behind a fence that almost excludes the ceaseless roar of motor traffic. The Kebun Raya was established in 1817, and on that morning the path passing beneath the tree was being re-set by a gardener, just as his father before him, and his grandfather before that had done. Each cobble was removed and re-set in its
bed with a steady rhythm that seemed eternal. Watching the workman, I saw continuity in a world utterly transformed.
The graves of two brave Dutchmen lay nearby, the biologists Kuhl and Van Hassalt. In the opening years of the nineteenth century they had worked for the Dutch East Indies Natural History Commission, documenting the seemingly inexhaustible natural wealth of what is now Indonesia. Of the thirteen commissioners sent out from Europe, only three had returned alive. But the treasures of natural history they obtained had filled the great natural history museum in Leyden. Among them were the first tree-kangaroo made known to the world and the first of many kinds of birds of paradise: exotic and outlandish creatures previously unimaginable to many Europeans.
Later that evening I sat in a cane chair in the venerable, whitewashed guesthouse in the gardens, watching fireflies and listening to cecaks—the ghostly pale geckoes found on every wall in the tropics. A young woman clad in an ornate traditional Javanese wrap padded silently into the room, carrying a glass of shaved ice and sweet orange juice. Somewhere, not too far away, the strains of the gamelan carried across the balmy evening air.
Suddenly an explosive, frog-like call shook the room: ‘Geck-Ko.’ I looked up to see a garishly pink and purple spotted, banana-sized lizard emerge from behind a hanging. Large of head, heavy of jaw and short of tail, it was the original gecko—and a giant of its kind. A second call, and a pair emerged onto the wall. They were hunting, and a cecak was their prey. The geckoes worked like pieces on a chessboard, herding the cecak and hoping to cut off its escape route at the nearby window. A dash too fast to see, and the checak was gone into the night.
Tomorrow I would strike out east, towards the Spice Islands, to carry on Kuhl and Van Hasselt’s work. I had been a week in Jakarta seeking the necessary permits—from the Indonesian science organisation LIPI, the social and political police, SOSPOL, and the Indonesian Police, POLRI. It was Ramadan, and the officials sat in their stiflingly hot offices, forbidden by their faith from eating, drinking or even swallowing their saliva between around 5 am and 5 pm. Their lips were crusted white and their eyes listless as I waited for them to stamp my papers. I might still have been waiting were it not for my colleague Boeadi.
I had first met the stocky Javanese man some months earlier, when I had detoured to Jakarta returning from a trip to Europe. Indonesia’s most respected field naturalist, Boeadi had met me at Soekarno-Hatta airport and hired a car to take us to Bogor. We arrived around lunchtime, and Boeadi led me into a warren of tiny shops in the market opposite the museum. There we settled into a Chinese restaurant in distant corner. When Boeadi ordered a pork dish, I understood why he had chosen such a hidden location: had any of his Muslim workmates seen him, it may have reflected badly.
Boeadi grew up in East Java, in the aftermath of World War II as Indonesia was struggling for independence from the Dutch. He became a wandering cigarette seller at fourteen, an occupation that enabled him to slip through the Dutch lines with messages for Indonesian freedom fighters. It was also the year of his circumcision, a rite performed in Java at adolescence. Boeadi was determined to avoid having it done by the village Imam. He saved his cigarette money so that he could be cut in a hospital, under an anaesthetic.
As we ate lunch that day, Boeadi spoke of his career as a wildlife researcher—of trapping Sumatran rhinos and tigers for breeding programs, of sleeping in remote jungle trees as leopards stalked below, and of climbing to the eternal snows of Mount Jaya in Papua as part of a military expedition in 1963. He had taught the soldiers how to live off the bush and still had a letter from President Sukarno thanking him for his efforts. Boeadi had visited pretty much every major island in the sprawling Indonesian archipelago by the time I met him. He was the grand old man of Indonesian zoology and had trained almost every forestry official in the service. Wherever we went Boeadi was treated like a god. To me, however, he was the funniest, most relaxed and enjoyable travel companion I’d ever had. We became true friends, he visiting me in Sydney, and me attending his daughter’s wedding in East Java.
But all that lay in the future on that first evening in 1989. The great forests of Java might be vanished into thin air, but in the east the green blanket of tropical forest remained all but unbroken, and largely unexplored. Nearly two centuries after Kuhl and Van Hasselt, the biological frontier with all its treasure of undescribed species was beckoning me.
I had initially wanted to work in Irian Jaya, but it had been incorporated into Indonesia only twenty years previously, and a sporadic civil war was being fought there. Instead, Boeadi suggested that we survey the north Moluccas. Drawn by the romance of islands like Ternate and Tidore—the sleeping one—I readily agreed. Like twin brothers these equatorial volcanic isles face one other across an emerald sea, each home to a venerable kingdom locked in perpetual struggle one with the other. They once influenced the world. Or rather, they were the centre of the world, for the whole world came to them.
It was to the fabled Spice Islands that Columbus bent his sails in 1492 (though America got in the way), and to which afterwards, as their ruined Dutch and Portugese forts and regal Sultan’s palaces attest, a world of merchants journeyed. Pasty-faced Dutchmen and Englishmen including the famous Raleigh, pig-tailed Chinamen and swarthy Yemenis in starched white thobes—all came for the same thing: the fruit of a laurel tree, known as nutmeg; and the unopened flower buds of a lilli-pilli, known as cloves. They, and the sublime feathers of the bird of heaven—the burung cendarawasih—were the riches of the very far east.
Why, you may ask, were such things only to be found at the ends of the Earth? Perched on the fractured edge of the Australian plate, the Spice Islands lie where east meets west. The clove and nutmeg are ancient Australasians, as are the sources of the Indonesian medicinals, kayu kulit putih (tea-tree oil) and kayu kulit lawang. All hail from a realm where soils are poor, making life difficult for trees. That is why Australasian plants protect what they grow by manufacturing the chemicals we call spices and medicinal oils. And those sublime predators, the cats, never reached that poor, isolated region, so its birds could dress in all the finery they wished.
Five centuries later, and at the other end of the archipelago, men would again gather from every corner of the globe, but this time not to make trade, but to wage war. The Second World War had a profound impact on this remote place, and it is still possible—or was when we did our work—to enter caves full of the remains of men whose bones, gasmasks and guns had lain undisturbed since last the guns fell silent in 1945.
To be honest, I did not consider it a great loss to be heading to the Spice Islands rather than Papua. When I was in my early thirties the mere mention of the Spice Islands triggered a yearning so fierce that I felt like an early spice trader bent on risking all to make a fortune. I’d spent all I had on a seventeenth-century Dutch map of the place, which hung in my study. Stained and yellowed, it had clearly seen sea work, having been plucked from a rutter—a seventeenth-century guide for navigators. Ornamented with sea-monsters and galleons, it depicted a tiny archipelago of half a dozen islands that straddled the equator. Ternate, Tidore, Motir, Makian, Pottebackers Eylandt. To a biologist they have special significance. Alfred Russell Wallace had devised his theory of evolution by natural selection while wracked by malaria in a hut on Ternate. Indeed the Spice Islands are part of Wallacea. But for all their biological interest, next to nothing had been published on the mammals that inhabit the islands. True, Wallace and a handful of European visitors had collected the odd specimen that lay stored in museums, but no modern survey had been done, and there was no book documenting the fauna.
Though civil war would eventually terminate my work there, I was fortunate to have worked in the Moluccas before ever a rifle was fired in anger between Christian and Muslim. But I am getting ahead of myself. The story of my journey towards the Spice Islands began long ago and far away from Indonesia, in a museum in East Berlin on 11 November 1989. There, I found myself studying a dusty museum cabinet
full of mammal specimens collected over a century before. Few institutions rival the Humboldt University Museum in Berlin in terms of their holdings of the Spice Islands’ mammals, so it was the logical place to start research prior to my first trip. I was studying in London at the time and a few days before my departure for Berlin, Erich Honecker, the longtime leader of East Germany, had resigned. The political situation was tense, and I worried that I might not be allowed to cross into the east. Then, thirty-six hours before I was supposed to board my flight, East Germany’s new leader Egon Krentz did something astonishing Facing mass demonstrations, he hastily made changes to travel restrictions for East Germans. Berlin Party boss Günter Schabowski was given the task of announcing the changes. He had not been briefed properly and fumbled spectacularly, saying in effect that anyone wishing to cross to the west could do so, effective immediately. No directives had been given to guards and those on border checkpoints, and the situation was soon uncontrollable. East Germans crossed into the west en masse, and it soon became clear that the division of Germany was at an end.
When I arrived in West Berlin it felt like walking into a never-ending party. After checking in to my hotel, I went downstairs for a meal—and found that I couldn’t spend my money. Deliriously happy middle-aged German men crowded the bar. They kept shouting rounds of beer and schnapps, while innumerable plates of sausages, sauerkraut and other snacks just appeared from thin air. Afterwards, a few of us went out to the Brandenburg Tor by bus, where again my offer to buy a ticket was waved aside. An enormous crowd had gathered, enjoying beer and listening to music, while men in business suits stood swinging at the wall with sledge hammers. Head-sized holes had already appeared, through which I could see nervous East German guards who looked all of fifteen years old, clinging to their rifles as they tried to ignore the demolition. People kept thrusting cans of cold beer towards them, but they looked terrified and refused to even look at the arms poking through the holes.