Finding Arcadia Read online

  Dr. Starr completes another loop of the table and stops to pick up a tray from the side of the room. On it are three small boxes, each covered by a coloured cloth. One red, one yellow, one blue—but there will be no boiled sweets today.

  “Now,” he continues, placing the tray in the centre of the table, “it would be impractical to bring an elephant into the drawing room and in any case Marwell doesn’t have one. It does, however, have a remarkable collection of some smaller creatures that can help demonstrate my point.”

  He lifts up the red cloth to reveal a small plastic cube inside which a dead moth has been mounted. Its pale wings are about two inches across and speckled with dots that give it a mottled appearance.

  “Meet Biston betularia, better known as the peppered moth. You can see from its wings how it got its name—these enabled it to hide from predators by blending into the bark of light-coloured trees and the lichen that sometimes covers them. It was common in England for hundreds of years. This example comes from the start of the nineteenth century.”

  Past tense because it died out? But today the theme is evolution rather than extinction.

  “Now, meet another moth.” The yellow cloth is removed to reveal a second plastic box with a moth that is the same shape and size as the first, but almost completely black in colour. “Would anyone like to hazard a guess at what this moth is called?”

  Biston betularia, presumably. But when?

  “Bison beetle?” Sebastian is trying to reproduce the Latin name of the first moth, but Dr. Starr charitably pretends that he is naming the second.

  “Well done, Sebastian! Yes, this is also Biston betularia—though now the name ‘peppered moth’ seems a little out of place. The black variant of this moth was virtually unknown when our pale friend was caught. Yet by the time his darker descendant here was captured at the end of the nineteenth century almost every single ‘peppered’ moth was actually black.”

  “Her,” she says quietly.

  “I beg your pardon?” Dr. Starr looks up and is about to say something, but hesitates and looks at the first moth more closely, noticing for the first time its elongated abdomen. He clears his throat. “So, when her descendant was captured, why had most of the moths changed colour?”

  “Poachers?” suggests Sebastian helpfully. The poor boy thinks he is on a roll.

  Dr. Starr bites his lip and looks expectantly for another answer. Any other answer.

  “Something to do with the environment,” says Henry. “And humans. You said they hid from predators on light-coloured trees. Did the trees change colour?”

  Of course: soot.

  “Indeed they did.” The bitten lip transforms into a smile. “The nineteenth century, you will recall, was the period of the Industrial Revolution. Vast amounts of coal were burnt to power factories that sprang up from London to Manchester. Soot killed the lichen and blackened the trees. And so?”

  Sebastian’s eyes light up. “Suddenly the peppery wings don’t hide the moths but make them stand out. So they all got eaten?”

  “Exactly,” says Dr. Starr with all the pride of a parent seeing a child take his tottering first steps. “Meanwhile, the tiny number of peppered moths that happened to be born with black wings found themselves at a distinct advantage. They were the ones able to thrive and in the space of less than a century became the dominant form.”

  But what is in the third box? The story surely doesn’t stop there.

  “Our tale has a slightly more optimistic coda,” Dr. Starr continues. “Clean air standards have improved considerably from Dickensian times. The trees regained their colour; the lichen returned. And our little black friends found that their day in the sun—albeit choked with smog for much of the time—had passed. And here we have an example of the peppered moth today.”

  With a flourish he lifts the blue cloth. It reveals another box, though this one is open. Startled by the sudden light, the peppered moth inside flaps its pale speckled wings into action and rises from the box, circling around briefly before flitting towards the safety of a dark corner.

  “So evolution can alter appearance, and humans can cause evolution.” He is building to something beyond the scope of the textbook. Echoes of Miss Alderman and her passion for monkeys.

  “But evolution can also shape behaviour. You’ve all presumably heard of the cuckoo’s unusual style of parenting. They are an example of a ‘brood parasite’, meaning an animal that relies on others to rear their young.”

  “Isn’t that a bit like shipping your kids off to boarding school?” Henry says under his breath.

  Dr. Starr catches the comment, but decides to let it pass. “Here we are talking about the most basic form of care,” he says, “watching over the egg, feeding the infant, all the way to independence. What’s more, this often happens without the host parents ever knowing that they have been tricked.

  “It can be seen among insects and fish, but is most spectacular in birds. Cuckoos simply lay their eggs in other birds’ nests and then trick or persuade those birds to care for them until hatching. Some cuckoos seem able to change the colour of their eggs to match those of the hosts. When a nest with eggs is left unattended, the cuckoo disposes of one and then lays her own egg in its place. The owner of the nest returns none the wiser and continues to care for the whole batch.”

  “That’s trickery,” Henry says. “But you said sometimes they ‘persuade’ the host?” He has probably read about fish that behave in this way; the feathered descendants of dinosaurs are more creative and more brutal in their methods.

  “Ah yes,” Dr. Starr responds. “Not all brood parasites are able to mimic egg colour, and some hosts are better than others at distinguishing the imposter egg. As a result, the host may toss the new egg out and continue caring for its own. This can lead to what some biologists call ‘mafia behaviour’ by the other bird. Any guesses what that might mean?”

  “They fit them out with cement shoes?” Sebastian is now trying to be amusing, an even weaker suit for him than trying to be correct.

  Dr. Starr pretends not to hear and looks at the other students, eventually settling on her. A raised eyebrow prompts her to speak.

  “It destroys the nest completely,” she says. “Punishing the bird, with the message that a refusal to care for my egg means that I will wipe out all of yours.”

  “Precisely.” He nods. “The brown-headed cowbird, for example—another brood parasite like the cuckoo—lays its eggs in a variety of other birds’ nests and then goes back to check on them periodically. If the parasite egg goes missing, the punishment—for want of a better word—can be severe.”

  The circling of the table resumes.

  “Once the chicks hatch, there is a different kind of problem. Eggshells might be similar in appearance, but these are completely different birds. Cuckoos look nothing like the host birds—robins, dunnocks, and so on—and once that becomes clear the cuckoo chick might be abandoned. So cuckoos tend to develop faster than other eggs and hatch first. Any guesses what they do then?”

  “Remove the competition?” she says, now keen to move him along to his destination.

  “Yes,” he nods again, perhaps eager also to reach his conclusion, or just happy to have someone actively engaged. “The cuckoo hatchling either rolls the other eggs out of the nest or attacks them. Some cuckoos are born with sharp hooks on their beaks that appear to have no other function than killing any other chicks in the same nest. After this mass murder, they are left as the only hatchling—most host birds then seem content to raise them as their own.

  “So what’s fascinating here is not simply that evolution has given rise to this parasitic behaviour. It’s that the actions of the cuckoo chick could not possibly have been taught. They do this within hours of birth, without interacting with their parent or indeed any other creature. It is instinctual, somehow encoded into their genetic makeup: literally natural born killers.”

  “That’s horrible,” Henry cannot help saying.

&n
bsp; “Morality has nothing to do with it,” Dr. Starr counters. “Or rather, morality would have something to do with it if morality provided an evolutionary advantage. Some biological anthropologists do argue that our human sensibilities evolved in just this way. The content of our moral code is part of a culture that is learned, but the capacity to be a moral creature is genetically determined.”

  Nature versus nurture all over again. Dr. Starr is at last getting to his point.

  “So human behaviour can affect evolution, and evolution can help shape behaviour. But what happens if we close this loop? Elephants with shorter tusks and peppered moths with different coloured wings were not ‘natural’ selection: they were a direct response to human preferences. The desire for ivory. The desire for factories. Have such human preferences started shaping our own evolution?”

  “What about car crashes?” says Henry.

  “Go on.”

  “Well, people like to be able to drive but every year something like a million people die on the roads. Presumably that includes some of the worst drivers, so are we evolving into better drivers?”

  “An interesting theory.” Dr. Starr’s hands come together, fingers intertwined. “If driving were an integral part of growing up and if only those with poorer attention or slower reaction times died on the roads, I suppose it is possible that the average attention span or reaction time might slowly improve. Poachers wiped out most of the big-tusked elephants quite quickly, leading to the change in tusk size of those that were left. But cars kill many more people than just the drivers, and technological improvements mean that they are safer than ever. The rise of autonomous or self-driving vehicles will reduce the risks even more.”

  He chuckles to himself. “You do remind me, however, of a professor I once had who advocated that primary schools should ideally be built next to a cliff on one side and a motorway on the other. Such schools should also, he argued, have no fences—the better to weed out the dull and the clueless of each generation.”

  A clap to focus his mind and theirs. “Actually, however, I am thinking of the opposite kind of change to the evolutionary process.” No one is biting. “Miss Greentree?”

  She has not put up her hand, but a response is expected. Human choices that are not improving or accelerating human evolution, but doing the opposite. Dr. Starr’s altruism gene run amok. “Medicine?” she offers. “Hospitals? Fertility treatment? Charity?”

  There is a spark in his eyes that she has not seen before. “Exactly! Our medical advances mean that many of those who, for whatever reason, would never have survived in the past—let alone reproduced—now reach maturity and pass on their genetic material to future generations. Evolution is slow, but such developments could halt it completely.

  “What is more, this is an evolutionary cul-de-sac of our own making. The very advantages that enabled humans to dominate the planet—our brains and our instinctive desire to form bonds with one another, to create communities—now give us the ability and the willingness to stop natural selection in its tracks.”

  So the answer is to cull the weak? Or does he want to empower the strong? The classroom falls silent for a moment.

  “What if Lamarck was right?” she says, thinking aloud.

  “I beg your pardon?” Too late, she realises that he had intended to halt the lesson there.

  “What if Lamarck was right. If it is possible for a species to change not just by killing off its weak but by passing on the best of itself to its young. It might not be at a genetic level, but, as you just said, natural selection has virtually no impact from one generation to the next. And in the case of humans it may have slowed to a halt completely.”

  “You’re talking about culture.” He is unimpressed. Disappointed, even? “There is a way out of the cul-de-sac, but it is not to rely on the better angels of our nature. It is to take charge of our destiny. But that is a topic for another day.”

  The rest of the afternoon is spent looking in more detail at the genetic processes that make evolution possible. The peppered moth is an unusually clear example as the colour of its body is determined by a single gene. The manner in which cuckoos and other brood parasites encode instinctual behaviour is more complicated and controversial. Videos of the murderous birds are watched; formaldehyde-filled jars with chicks at various stages of development are studied. So curious that the cuckoo developed this reputation of being nature’s cheat, an animal that outsources the most fundamental functions of life—raising one’s young—with cuckoldry among humans being the ultimate humiliation of a husband who raises another man’s children. How is it that this terrible image of the cuckoo exists alongside celebration of it as the harbinger of spring, its call echoing in thousands upon thousands of homes in the form of cuckoo clocks?

  Dr. Starr, moving restlessly around the table, peering over shoulders, remains an enigma. She needs more information. His background; possible connections to Miss Alderman and the former Headmaster. Why he has come to the Priory School now. What his connection to Henry is.

  At four o’clock they are dismissed for a break and she walks out into the zoo proper alongside her classmate. The grounds have just closed to the public and the babble of visitors is replaced by the tranquillity of twilight, broken only by the occasional call of an animal and the distant hum of a plane.

  “So how do you know Dr. Starr?” she asks.

  Henry tries to hide a grin. “You were mostly right,” he says. “He is a family friend—but not an old one. My parents have a house in the Cotswolds and we spent a few weeks there over the summer, fly fishing and going on walks. Dr. Starr was renting in the area also and we caught up over a few meals. My father likes to pretend he’s an intellectual, so when he heard that Starr was a professor Dad insisted that he sit with us.”

  “Was it just chance that you bumped into one another?” They continue walking past some bored-looking gibbons. The sound of the plane—light aircraft?—gets closer.

  “I should think so,” Henry replies, giving the gibbons a wave. They stare glumly back. “We go there most years and we’d not seen him before.”

  A predictable pattern, not random variation. Unnatural selection? “So what did you talk about?” She tries to keep her voice light. The engine noise is too high-pitched. Could the plane be a model aircraft?

  “Oh this and that.” He sees a sign pointing to zebras and angles towards the path heading in that direction. “My father is such a blowhard that he did a lot of the talking. But Dr. Starr said he was moving to the Priory School and so he asked me a bit about that.”

  “Quite a coincidence bumping into him in the Cotswolds.” They continue walking for a moment. “Did he ask about me?”

  Henry stops. “No,” he says firmly. “For Heaven’s sake, Arcadia, if there was anything suspicious about him I would tell you of all people. Why do you think that he’d be asking about you?”

  “It’s too much of a coincidence. He, Milton, Miss Alderman all did science at Oxford around the same time.”

  “Lots of people go to Oxford, Arcadia. You’ll go there one day if you decide that you want to.”

  She lets that pass. “And just to happen to meet you and your family before starting here?”

  “Another coincidence. What’s that James Bond line? ‘Once is happenstance. Twice is coincidence. The third time it’s enemy action’?”

  Perhaps Goldfinger was right; perhaps it is just coincidence. The buzzing noise has continued to get closer and for the first time she sees it against the reddened horizon. Not a model aircraft but a football-sized drone—a quadcopter hovering some hundred yards away. Occasionally used for deliveries, they are also popular with hobbyists. Most have a built-in camera.

  They have reached the zebras, standing in a wide field and absent-mindedly munching on grass. It is almost time to go back, but she lingers in the moment.

  “It must be strange for the animals here,” she muses. “Having evolved to deal with the African savannah, lions and leopards hu
nting you, they now find themselves on the grounds of an English country manor. All their needs are provided for, their waste is carried away. But they live under constant scrutiny, an assortment of people filing past to gawk at them, take a photo, and move on.”

  The drone continues to hover. Watchful. Watching? Maybe Henry is right, maybe she is being paranoid.

  “Come on,” she says. “It’s time to go back.”

  After they have walked for a few minutes, her phone chimes within her bag, announcing a text message. It is from Lestrange:

  Dear Miss G, have insurance policy. Cannot send to you but call to discuss. Lestrange.

  “Miss G”—how formal. He is evidently wary of being in a texting relationship with a teenage girl. News of Pratt’s death has not yet been made public and she is not yet ready to discuss it with Henry. She quickly types a reply as they continue towards Marwell Hall.

  Look for suicide clause. Any luck on the ice? A

  The buzzing noise has followed them from the field. She sends the message, but instead of dropping the phone back in her bag she switches on the camera function and reverses it so that her face now fills the screen.

  “Are you taking a selfie, Arcadia?” Henry laughs. “I didn’t think you approved of such things.”

  “I don’t, normally,” she replies, zooming in on her left ear. The light is terrible and the lens on the front-facing camera is inferior to the main camera, but it is sufficient to get an image of the drone’s outline against the fading light.

  He sees what she is doing. “Is that the drone that was near the zebras?” He starts to turn around but a gentle hand on his shoulder stops him.

  “Yes,” she replies. “Their range can be a couple of miles, but my guess is that in this light the operator won’t be too far away.”

  “What are you going to do?” They have reached the entrance to Marwell Hall and Henry opens the door for her.

  “Officially,” she says, stepping inside, “I am going in search of a bathroom. That’s what you can tell Dr. Starr.”