At Home

• CHAPTER XI •

THE STUDY

I

In 1897, a young ironmonger in Leeds named James Henry Atkinson took a small piece of wood, some stiff wire, and not much else, and created one of the great contraptions of history: the mousetrap. It is one of several useful items—the paper clip, the zipper, and the safety pin are among the many others—that were invented in the late nineteenth century and were so nearly perfect from the outset that they have scarcely been improved on in all the decades since. Atkinson sold his patent for £1,000, a very considerable sum for the time, and went on to invent other things, but nothing that secured him more money or immortality.

Atkinson’s mousetrap, manufactured under the proprietary name Little Nipper, has sold in the tens of millions, and continues to dispatch mice with brisk and brutal efficiency all over the world. We own several Little Nippers ourselves, and hear the dreadful snap of a terminal event far more often than we would wish to. Two or three times a week in winter we catch a mouse, nearly always in the same place, in this bleak, small room at the end of the house.

Although study makes it sound like a significant space, it is really just a glorified storeroom, too dark and cold even in mild months to encourage much lingering. This is another room that doesn’t appear on Edward Tull’s original plans. Presumably, Mr. Marsham had it added because he needed an office in which to write his sermons and receive parishioners—particularly, I daresay, the more unrefined and muddy-booted of them; the squire’s wife would almost certainly have been invited into the more comfortable parlor next door. These days the study is the final refuge of old furniture and pictures that one member of the marriage partnership admires and the other would happily see on a bonfire. Almost the only reason we go in there now is to check the mousetraps.

Mice are not easy creatures to figure. There is for a start their remarkable gullibility. When you consider how easily they are taught to find their way around mazes and other complex environments in labs, it is surprising that nowhere have they grasped that a dab of peanut butter on a wooden platform is a temptation worth resisting. No less mysterious in our house is their predilection—I might almost say their determination—for dying in this room, the study. It is not only the coldest room in the house but the farthest from the kitchen and all the biscuit crumbs and fugitive grains of rice and other morsels that end up on the floor and are there for the taking. Mice give the kitchen a wide berth (probably, it has been suggested to us, because our dog sleeps there) and mousetraps placed there, however generously baited, capture nothing but dust. It is to the study that our mice seem fatefully drawn, which is why I thought this might be the appropriate place to consider some of the many living things that dwell with us.

Wherever there are humans there are mice. No other creatures live in more environments than the two of us do. House mice—Mus musculus, as they are known on formal occasions—are wondrously adaptable with regard to environment. Mice have even been found living in a refrigerated meat locker kept permanently chilled at –10 degrees Celsius. They will eat almost anything. They are next to impossible to keep out of a house: a normal adult can squeeze through an opening just three-eighths of an inch wide, a gap so very tight that you would almost certainly bet good money that no grown mouse could possibly squeeze through it. They could. They can. They very often do.

Once in, mice breed prodigiously. In optimum conditions (and in most houses conditions seldom are other than optimal) a female mouse can start breeding at six to eight weeks old and can give birth monthly thereafter. A typical litter consists of six to eight offspring, so numbers can very quickly mount up. Two mice, breeding prolifically, could theoretically produce a million descendants in a year. That doesn’t happen in our homes, thank goodness, but very occasionally mouse numbers do get completely out of control. Australia seems to be particularly propitious in this respect. In one famous outbreak in 1917, the town of Lascelles, in western Victoria, was overrun with mice after an unusually warm winter. For a short but memorably lively period, mice existed in Lascelles in such densities that every horizontal surface became a frantic mass of darting bodies. Every inanimate object writhed under a furry coating. There was nowhere to sit. Beds were unusable. “The people are sleeping on tables to avoid the mice,” one newspaper reported. “The women are kept in a constant state of terror, and the men are kept busy preventing the mice from crawling down their coat collars.” Over fifteen hundred tons of mice—perhaps a hundred million individuals—were killed before the outbreak was defeated.

James Henry Atkinson’s patent drawing for the “Little Nipper” mousetrap, 1899 (photo credit 11.1)

Even in comparatively small numbers mice can do a lot of damage, particularly in food storage areas. Mice and other rodents consume about a tenth of America’s annual grain crop—an astonishing proportion. Each mouse voids about fifty pellets a day, and that results in a lot of contamination, too. Because of the impossibility of achieving perfection in storage, hygiene regulations in most places allow up to two fecal pellets per pint of grain—a thought to bear in mind the next time you look at a loaf of whole grain bread.

Mice are notable vectors of disease. Hantavirus diseases, a family of respiratory and renal disorders that are always disagreeable and often lethal, are particularly associated with mice and their droppings. (The name hanta comes from a river in Korea where the disease was first noted by Westerners during the Korean War.) Fortunately, hanta viruses are fairly rare, since few of us breathe in the frail vapors of mouse droppings, but if you get down on your hands and knees in the vicinity of infected waste—to crawl around in an attic, say, or set a trap in a cupboard—you run the risk in many countries of infection. Globally, over two hundred thousand people a year are infected with hanta viruses, which kill between 30 and 80 percent of their victims, depending on how quickly and well they are treated. In the United States, between thirty and forty people a year contract a hantavirus, and about a third of those people die. In Great Britain, happily, these diseases remain unrecorded. Mice have also been implicated in occurrences of salmonellosis, leptospirosis, tularemia, plague, hepatitis, Q fever, and murine typhus, among many others. In short, there are very good reasons for not wanting mice in your house.

Almost everything that could be said of mice applies equally, but with multiples, to their cousins the rats. Rats are more common in and around our houses than we care to think. Even the best homes sometimes have them. They come in two principal varieties in the temperate world: the emphatically named Rattus rattus, which is alternatively (and tellingly) known as the roof rat, and Rattus norvegicus, or the Norway rat. The roof rat likes to be up high—in trees and attics principally—so the scurryings you hear across your bedroom ceiling late at night may not be, I’m sorry to say, mice. Fortunately, roof rats are rather more retiring than Norway rats, which live in burrows and are the ones you see scuttling through sewers in movies or prowling around garbage cans in back alleys.*

We associate rats with conditions of poverty, but rats are no fools: they sensibly prefer a well-heeled home to a poor one. What’s more, modern homes make a delectable environment for rats. “The high protein content that characterizes the more affluent neighborhoods is particularly enticing,” James M. Clinton, a U.S. health official, wrote some years ago in a public health report that remains one of the most compelling, if unnerving, surveys ever taken of the behavior of domestic rats. It isn’t merely that modern houses are full of food, but also that many of them dispose of it in ways that make it practically irresistible. As Clinton put it: “Today’s garbage disposals in homes pour out a bountiful, uniform, and well-balanced food supply for rats.” According to Clinton, one of the oldest of all urban legends, that rats come into homes by way of toilets, is in fact true. In one outbreak, rats in Atlanta invaded several homes in wealthy neighborhoods, and bit more than a few people. “On several occasions,” Clinton reported, “rats were found alive in covered toilet bowls.” If ever there was a reason to put the lid down, this could be it.

Once in a domestic environment, most rats show little fear “and will even deliberately approach and make contact with motionless persons.” They are particularly emboldened in the presence of infants and the elderly. “I have verified the case of a helpless woman attacked by rats while she slept,” Clinton reported. He went on: “The victim, an elderly hemiplegic, hemorrhaged extensively from multiple rat-bite wounds and died despite emergency hospital treatment. Her 17-year-old granddaughter asleep in the same room at the time of the attack was unharmed.”

Rat bites are almost certainly underreported because only the most serious cases attract attention, but even using the most conservative figures, at least fourteen thousand people in the United States are attacked by rats each year. Rats have very sharp teeth and can become aggressive if cornered, biting “savagely and blindly, in the manner of mad dogs,” in the words of one rat authority. A motivated rat can leap as high as three feet—high enough to be considerably unnerving if it is coming your way and is out of sorts.

The usual defense against rat outbreaks is poison. Poisons are often designed around the curious fact that rats cannot regurgitate, so they will retain poisons that other animals—pet dogs and cats, for instance—would quickly throw up. Anticoagulants are commonly used, too, but there is evidence to suggest that rats are developing resistance to them.

Rats are smart and often work cooperatively. At the former Gansevoort poultry market in Greenwich Village, New York, pest control authorities could not understand how rats were stealing eggs without breaking them, so one night an exterminator sat in hiding to watch. What he saw was that one rat would embrace an egg with all four legs, then roll over on his back. A second rat would then drag the first rat by its tail to their burrow, where they could share their prize in peace. In a similar manner workers at a packing plant discovered how sides of meat, hanging from hooks, were knocked to the floor and devoured night after night. An exterminator named Irving Billig watched and found that a swarm of rats formed a pyramid underneath a side of meat, and one rat scrambled to the top of the heap and leaped onto the meat from there. It then climbed to the top of the side of meat and gnawed its way through it around the hook until the meat dropped to the floor, at which point hundreds of waiting rats fell upon it.

When eating, rats will unhesitatingly gorge if plenty is available, but they can also get by on very little if necessary. An adult rat can survive on less than an ounce of food a day and as little as half an ounce of water. For pleasure they seem to enjoy gnawing on wires. Nobody knows why, because wires clearly are not nutritious and offer nothing in return except the very real prospect of a fatal shock. Still, rats can’t stop themselves. It is believed that as many as a quarter of all fires that can’t otherwise be explained may be attributed to rats chewing on wires.

When they are not eating, rats are likely to be having sex. Rats have a lot of sex—up to twenty times a day. If a male rat can’t find a female, he will happily—or at least willingly—find relief in a male. Female rats are robustly fecund. The average adult female Norway rat produces 35.7 offspring a year, in litters of 6 to 9 at a time. In the right conditions, however, a female rat can produce a new litter of up to 20 babies every three weeks. Theoretically, a pair of breeding rats could start a dynasty of 15,000 new rats in a year. That doesn’t happen in practice, because rats die a lot. Like a lot of other animals, they are more or less programmed by evolution to expire fairly easily. The annual mortality rate is 95 percent. A determined extermination campaign will normally reduce rat populations by 75 percent or so, but once the campaign stops the rat population will recover in six months or less. In short, an individual rat hasn’t got great prospects in life, but his family is effectively ineradicable.

Mostly, however, rats are just immensely lazy. They spend up to twenty hours a day asleep, normally emerging to look for food just after sunset. They seldom venture more than 150 feet if they can possibly help it. This may be part of a survival policy, for mortality rates rocket whenever they are compelled to migrate.

When rats are mentioned in a historical context, the one topic that invariably follows is plague. This may be not quite fair. For one thing, rats don’t actually infect us with plague. Rather, they harbor the fleas (that harbor the bacteria) that spread the disease. Plague kills rats just as energetically as it kills us. Indeed, it kills many other things, too. One of the signs of a plague outbreak is lots of dead dogs, cats, cows, and other animals scattered about. Fleas much prefer the blood of furry creatures to the blood of humans, and generally turn to us only when nothing better is available. For that reason, modern epidemiologists in places where plague is still common—notably parts of Africa and Asia—generally avoid culling rats and other rodents too enthusiastically during outbreaks. In a very real sense there is no more welcome time for rats to be around than when plague is rampant. Anyway, more than seventy other creatures besides rats—including rabbits, voles, marmots, squirrels, and mice—have been implicated in the spread of plague. Moreover, possibly the very worst plague outbreak in history doesn’t seem to have involved rats at all, at least not in England. Long before the notorious Black Death of the fourteenth century, an even more ferocious plague devastated Europe in the seventh century. In some places almost everyone died. The Venerable Bede, in his history of England written in the following century, says that when the pestilence reached his monastery at Jarrow, it killed everyone except the abbot and one boy—a mortality rate considerably over 90 percent. Whatever was the source of its spread, it wasn’t rats, it seems. No rat bones from the seventh century have been found anywhere in Britain—and people have looked hard. One excavation in Southampton collected fifty thousand animal bones from in and around a cluster of dwellings; none came from a rat.

It has been suggested that some outbreaks attributed to plague may not have been plague at all, but ergotism, a fungal disease of grain. Plague didn’t come at all to many cold, dry northern places—Iceland escaped entirely, as did much of Norway, Sweden, and Finland—even though those places had rats. At the same time, plague was associated with miserably wet years almost everywhere it appeared—the very circumstances that would tend to produce ergotism. The one problem with the theory is that the symptoms of ergotism are not much like those of plague. It may be that the word pestilence was used loosely or vaguely and simply misinterpreted by later historians.

Even just a generation or two ago, rat numbers in urban areas may have been considerably higher than now. The New Yorker reported in 1944 that a team of exterminators working in a well-known (but carefully unidentified) hotel in Manhattan caught 236 rats in the basement and subbasement in three nights. At about the same time, rats all but took over the aforementioned Gansevoort poultry market. They invaded in such numbers that secretaries sometimes found rats leaping out of their desk when the drawers were opened. Exterminators were called in and caught four thousand rats in a matter of days, but they couldn’t make the market ratproof. In the end it was shut down.

It is commonly written that there is one rat for every human being in a typical city, but studies have shown that to be an exaggeration. The actual figure is more like one rat for every three dozen people. Unfortunately, that still adds up to a lot of rats—a quarter of a million in New York City, for instance.

II

The real life in your house is at a much smaller scale. Down at the realm of the very tiny, your house teems with life: it is a veritable rain forest for crawling, clambering things. Armies of tiny creatures patrol the boundless jungles of your carpet fibers, paraglide amid floating motes of dust, crawl across the bedsheets at night to graze on the vast, delicious, gently heaving mountain of slumbering flesh that is you. These creatures exist in numbers you cannot comfortably imagine. Your bed alone, if it is averagely clean, averagely old, averagely dimensioned, and turned averagely often (which is to say almost never) is likely to be home to some two million tiny bed mites, too small to be seen with the naked eye but unquestionably there. It has been calculated that if your pillow is six years old (which is the average age for a pillow), one-tenth of its weight will be made up of sloughed skin, living and dead mites, and mite dung—or frass, as it is known to entomologists.

Clambering among the bed mites, on a much more gigantic scale, might also these days be lice, for it appears that these creatures, once nearly vanquished, are making a comeback. Like rats, lice come in two principal varieties: Pediculus capitas, or head lice, and Pediculus corporis, or body lice. These latter (familiarly known as cooties, probably from the Malay term kutu) are relative newcomers on the bodily irritants scene. They evolved sometime in the last fifty thousand years from head lice. Of the two, head lice are much smaller (they are about the size of a sesame seed, and actually look much the same) and so harder to detect. An adult female head louse will lay three to six eggs per day. Each louse can live for about thirty days. Lice eggs are called nits. Lice have developed an increasing resistance to pesticides, but the greatest reason for their increase, it seems, is low-temperature wash cycles in washing machines. As Dr. John Maunder of the British Medical Entomology Centre has put it: “If you wash lousy clothing at low temperatures, all you get is cleaner lice.”

Historically, the most common bedroom dread was bedbugs—Cimex lectularius, as the little blood suckers are scientifically known. Bedbugs made sure that no one ever slept alone. In former times, people were driven half mad by bugs and the desire to be rid of them. When Jane Carlyle discovered that bedbugs had invaded her housekeeper’s bed, she had the bed taken to pieces and carried to the garden, where each piece was washed with chloride of lime, then immersed in water for two days to drown any bugs that survived the disinfectant. The bedding meanwhile was taken to a sealed room and dusted repeatedly with disinfectant powder until no more bugs emerged. Only then was it put back together and the housekeeper allowed to resume a normal night’s sleep, in a bed that was now almost certainly at least mildly toxic to her as well as to any insect life that dared to creep back in.

Even when beds weren’t actively infested, it was routine to take them apart at least once a year and paint them with disinfectant or varnish as a precaution. Manufacturers often advertised how quickly and easily their beds could be dismantled for an annual maintenance. Brass beds became popular in the nineteenth century not because brass was suddenly thought a stylish metal for bedsteads, but because it gave no harbor to bedbugs.

Like lice, bedbugs are making an unwelcome comeback. For most of the twentieth century they were virtually extinct in most of Europe and America thanks to the rise of modern insecticides, but in recent years they have been vigorously rebounding. No one is sure why. It may have something to do with more international travel—people bringing them home in their suitcases and so on—or that they are developing greater resistance to the things we spray at them. Whatever it is, they are suddenly being noticed again. “Some of the best hotels in New York have them,” the New York Times quoted one expert as saying in a report in 2005. The Times article went on to note that because most people have no experience of bedbugs and don’t know what to look out for, they are likely to discover they are infested only when they wake up and find themselves lying in a swarm of them.

If you had the right equipment and a peculiar measure of motivation, you could find numberless millions of dinky creatures living with you—vast tribes of isopods, pleopods, endopodites, myriapods, chilopods, pauropods, and other all-but-invisible specks. Some of these little creatures are practically ineradicable. An insect named Niptus hololeucus has been found living in cayenne pepper and in the cork stoppers of cyanide bottles. Some, like flour mites and cheese mites, dine with you pretty regularly.

Move down to the next level of living things, to the world of microbes, and the numbers swell beyond counting. Your skin alone is home to about a trillion bacteria. Inside you are many thousands of trillions more, many of them engaged in necessary and helpful tasks like breaking down food in the gut. Altogether you hold about a hundred quadrillion bacterial cells in your body. If you took them out and put them in a pile, they would weigh about four pounds. Microbes are so ubiquitous that we easily forget that a large part of every modern house is taken up with heavy metal objects—refrigerators, dishwashers, washing machines—that exist exclusively to kill or suppress them. Getting germs out of our lives is a kind of endless daily quest for most of us.

The most celebrated germ expert in the world is almost certainly Dr. Charles P. Gerba of the University of Arizona, who is so devoted to the field that he gave one of his children the middle name Escherichia, after the bacterium Escherichia coli. Dr. Gerba established some years ago that household germs are not always most numerous where you would expect them to be. In one famous survey he measured bacterial content in different rooms in various houses and found that typically the cleanest surface of all in the average house was the toilet seat. That is because it is wiped down with disinfectant more often than any other surface. By contrast the average desktop has five times more bacteria living on it than the average toilet seat.

The dirtiest area of all was the kitchen sink, closely followed by the kitchen counter, and the filthiest object was the kitchen washcloth. Most kitchen cloths are drenched in bacteria, and using them to wipe counters (or plates or breadboards or greasy chins or any other surface) merely transfers microbes from one place to another, affording them new chances to breed and proliferate. The second most efficient way of spreading germs, Gerba found, is to flush a toilet with the lid up. That spews billions of microbes into the air. Many stay in the air, floating like tiny soap bubbles, waiting to be inhaled, for up to two hours; others settle on things like your toothbrush. That is, of course, yet another good reason for putting the lid down.

Almost certainly the most memorable finding of recent years with respect to microbes was when an enterprising middle school student in Florida compared the quality of water in the toilets at her local fast-food restaurants with the quality of the ice in the soft drinks, and found that in 70 percent of outlets she surveyed the toilet water was cleaner than the ice.

What is perhaps most remarkable about all these multitudinous life forms is how little we sometimes know about them—and how recently what we do know has been learned. Bed mites weren’t discovered at all until 1965, even though millions of them exist in every bed. As late as 1947, a medical correspondent for The New Yorker could write: “Mites are only infrequently found in this country and until recently were practically unknown in New York City.” Then, in the late 1940s, residents of an apartment complex called Kew Gardens in Queens, New York, began sickening in large numbers with flulike symptoms. The malady was known as “the Kew Gardens mystery fever” until an astute exterminator noticed that mice were also getting sick and discovered on close inspection that tiny mites living in their fur—the very mites that were supposed not to exist in America in large numbers—were transmitting rickettsialpox, a kind of spotted fever, to apartment dwellers.

Similar degrees of ignorance have long applied to many larger creatures, not least one of the most important and least understood of all animals that are sometimes found in modern houses: bats. Hardly anybody likes bats, which is truly unfortunate because bats do much more good than harm. They eat enormous quantities of insects, to the benefit of crops and people alike. Brown bats, the most common species in America, consume up to six hundred mosquitoes per hour. Tiny pipistrelle bats—which weigh no more than a small coin—vacuum up three thousand insects apiece in the course of a night’s swoopings. Without bats there would be a lot more midges in Scotland, chiggers in North America, and fevers in the tropics. Forest trees would be chewed to pieces. Crops would need more pesticides. The natural world would become a very stressed place. Bats are also vital to the life cycles of many wild plants through pollination and seed dispersal. A seba bat—a tiny bat in South America—will eat as many as sixty thousand tiny seeds per night. The seed distribution of a single colony of seba bats—about four hundred bats—can produce nine million seedlings of new fruit trees a year. Without the bats, those fruit trees wouldn’t happen. Bats are also critical to the survival in the wild of avocados, balsa, bananas, breadfruit, cashews, cloves, dates, figs, guavas, mangoes, peaches, and saguaro cactus, among others.

The world has far more bats than most people realize. In fact, about a quarter of all mammal species—some eleven hundred in all—are bats. They range in size from tiny bumblebee bats, which really are no bigger than bumblebees and therefore are the smallest of all mammals, up to the magnificent flying foxes of Australia and south Asia, which can have wingspans of six feet.

At times in the past attempts have been made to capitalize on bats’ special qualities. In the Second World War, the American military invested a great deal of time and money in an extraordinary plan to arm bats with tiny incendiary bombs and to release them in vast numbers—as many as a million at a time—from planes over Japan. The idea was that the bats would roost in eaves and roof spaces, and that soon afterward tiny detonators on timers would go off and they would burst into flames, causing hundreds of thousands of fires.

Creating sufficiently tiny bombs and timers required a great deal of experiment and ingenuity, but finally in the spring of 1943 work had progressed sufficiently that a trial was set to take place at Muroc Lake, California. It would be putting it mildly to say that matters didn’t go quite to plan. Remarkably for an experiment, the bats were fully armed with live bomblets when released. This proved not to be a good idea. The bats failed to light on any of the designated targets, but did destroy all the hangars and most of the storage buildings at the Muroc Lake airport, as well as an army general’s car. The general’s report on the day’s events must have made interesting reading. In any case, the program was canceled soon afterward.

A rather less harebrained, but ultimately no more successful, plan to make use of bats was conceived by a Dr. Charles A. R. Campbell of Tulane University Medical School. Campbell’s idea was to build giant “bat towers,” where bats would roost and breed, and then go out to eat mosquitoes. This, Campbell believed, would substantially reduce malaria and also provide guano in commercially worthwhile quantities. Several of the towers were built, and some actually still stand, if precariously, but they never worked. Bats, it turns out, don’t like to be told where to live.

In America, bats were persecuted by health officials for years because of inflated—and at times irrational—concerns that they carried rabies. The story began in October 1951 when an anonymous woman in west Texas, the wife of a cotton planter, came across a bat in the road outside her house. She thought it was dead, but when she bent to look at it, it leaped up and bit her on the arm. This was highly unusual. American bats are all insectivores and none had ever been known to bite a human. She and her husband disinfected and dressed the wound—it was just a small wound—and didn’t think anything more of it. Three weeks later the woman was admitted to a hospital in Dallas in a delirious condition. She was “wildly agitated,” and unable to speak or swallow. Her eyes were filled with terror. She was beyond help. Rabies can be successfully treated, but only if the treatment is immediate. Once symptoms start, it’s too late. After four days of unutterable distress, the woman slipped into a coma and died.

Now scattered cases of people being bitten by rabid bats began to crop up in other locations—two in Pennsylvania; one each in Florida, Massachusetts, and California; two more in Texas. All this was over the space of four years, so it was hardly rampant, but it did cause concern. Finally, on New Year’s Day 1956, a public health official in Texas, Dr. George C. Menzies, entered a hospital in Austin with rabies symptoms. Menzies had been studying caves in central Texas for evidence of rabies-bearing bats, but hadn’t been bitten or otherwise exposed to rabies as far as anyone knew. Yet somehow he became infected, and after just two days’ care he died in the usual hideous manner, in discomfort and terror, his eyes like saucers.

The case was widely reported and resulted in a kind of vengeful hysteria. Officials at the highest levels concluded that extermination was an urgent and necessary step. Bats became the most friendless creatures in America. Years of steady persecution followed, and bat populations in many places suffered shocking depredations. In one case, the largest bat colony in the world, at Eagle Creek, Arizona, experienced a population fall from thirty million to three thousand in a matter of years.

Merlin D. Tuttle, America’s leading bat authority and founder of Bat Conservation International, a charity for bats, related a case, reported in The New Yorker in 1988, in which public health officials in Texas told a farmer that if he didn’t kill the bats in a cave on his land, he and his family and their livestock would be at grave risk of contracting rabies. At their instructions, the farmer filled the cave with kerosene and lit it. The conflagration killed about a quarter of a million bats. When Tuttle interviewed the farmer later, he asked him how long his family had owned the property. About a century, the farmer replied. And in all that time, Tuttle went on, had they ever been troubled by rabies? No, the farmer responded.

“And when I explained to him the value of the bats and what he’d done, he actually broke down and cried,” Tuttle said. In fact, as Tuttle pointed out, “more people die of food poisoning at church picnics annually than have died in all history from contact with bats.”

Today bats are among the most endangered of all animals. About a quarter of bat species are on extinction watch lists—that is an amazingly and indeed appallingly high proportion for such a vital creature—and over forty species teeter on the very edge of extinction. Because bats are so reclusive and often so difficult to study, much about their population numbers remains uncertain. In Britain, for example, it is unknown whether there are seventeen surviving species of bats or sixteen. Authorities haven’t got enough evidence to decide whether the greater mouse-eared bat is extinct or just laying very low.

What is certain is that matters everywhere may be about to get much worse. In early 2006 a highly lethal new fungal disease, called white-nose syndrome (because it turns the hair around the victims’ noses white), was discovered among hibernating bats in a cave in New York. The disease kills up to 95 percent of the bats that it infects. It has now spread to half a dozen other states and will almost certainly spread farther. As of late 2009, scientists still had no idea what it is about the fungus that kills its host, how it spreads, where it originated, or how to stop it. All that is certain is that the fungus is specially adapted to survive in cold conditions—not good news for the bats of much of North America, Europe, and Asia.

III

The direction of movement for populations is not always downward, it must be said. Sometimes populations boom, occasionally in ways that shape history. Never has that been more true than in 1873, when farmers in the western United States and across the plains of Canada experienced a devastating visitation unlike anything anyone had ever seen before. From out of nowhere there came swarms of Rocky Mountain locusts—great chirring masses of motion and appetite that blotted out the sun and devoured everything in their path. Wherever the swarms landed, the effects were appalling. They stripped clean fields and orchards. They ate laundry off lines and wool off the backs of living sheep. They ate leather and canvas and even the handles of wooden tools. One amazed witness reported them landing in such numbers that they put out a good-sized fire. It was, according to most witnesses, like experiencing the end of the world. The noise was deafening. One swarm was estimated as being 1,800 miles long and perhaps 110 miles wide. It took five days to pass. It is thought to have contained at least 10 billion individual insects, but other estimates have put the figure as high as 12.5 trillion, with a massed weight of 27.5 million tons. It was almost certainly the largest gathering of living things ever seen on Earth. Nothing would deflect them. When two swarms met, they would push through each other and emerge in unbroken ranks on the other side. No amount of battering them with shovels or spraying with insecticide made any measurable impact.

This was exactly at a time when people were moving in vast numbers into the western United States and Canada, and creating a new wheatbelt across the great plains. Nebraska’s population, for instance, went from twenty-eight thousand to over a million in one generation. Altogether four million new farms were created west of the Mississippi in the period after the U.S. Civil War, and many of these new farmers were heavily indebted both with mortgages on their houses and land and with loans on flotillas of new equipment—reapers, threshers, harvesters, and so on—needed to farm on an industrial scale. Hundreds of thousands of others had invested huge sums in railroads, grain silos, and businesses of every type to support the booming populations of the West. Now vast numbers of people were being literally wiped out.

At the end of the summer, the locusts vanished, and a measure of hopeful relief crept in. But the optimism was misplaced. The locusts returned in the following three summers, each time in larger numbers than before. The unnerving thought that life in the West might become untenable began to take hold. No less alarming was the thought that the locusts could spread eastward and begin to devour the even richer farmlands of the Midwest and the East. There has never been a darker or more helpless moment in the whole of American history.

And then it all just came to an end. In 1877, the swarms were much reduced and the locusts within them seemed curiously lethargic. The next year they didn’t come at all. The Rocky Mountain locust (its formal name was Melanoplus spretus) didn’t just retreat but vanished altogether. It was a miracle. The last living specimen was found in Canada in 1902. None has been seen since.

It took more than a century for scientists to work out what had happened, but it appears that the locusts retired every winter to hibernate and breed in the loamy soils abutting the winding rivers of the high plains east of the Rockies. These, it turned out, were the very places where new waves of incoming farmers were transforming the land through ploughing and irrigation—actions that killed the locusts and their pupae as they slept. They couldn’t have devised a more effective remedy if they had spent millions of dollars and studied the matter for years. No extinction can ever be called a good thing, but this was probably as close to positive as such an event can get.

Had the locusts continued to thrive, the world would have been a very different place. Global agriculture and commerce, the peopling of the West, and ultimately the fate of our Old Rectory, as well as almost everything else beyond, connected to, and in between, would have been profoundly reshaped in ways we can scarcely imagine. American farmers in the last quarter of the nineteenth century were already gripped with a form of angry populism that was deeply resentful of banks and big business, and these feelings were widely echoed in the cities, particularly among newly arrived immigrants. Had agriculture collapsed sufficiently to produce widespread hardship and hunger, there might well have been an overwhelming rush to socialism. There were certainly many who ardently desired such an outcome.

Instead, of course, matters settled down, the West resumed its long expansion, America became the breadbasket of the world, and the British countryside went into a long tailspin from which it has never entirely recovered. That is a story that we shall get to in due course, but meanwhile let’s step into the garden and consider why so much of that landscape was, and indeed remains, so very attractive to be in.

* The Norway rat was often in the past called the brown rat, and the roof rat has been called the black rat. However, the names are misleading—the color of a rat’s fur isn’t a reliable indicator of anything—so rodentologists now nearly always avoid the terms.