Horizon

by Barry Lopez

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  BEHIND ME, now that Captain Moreno had taken the helm, the wake of the Beagle III was straight as a runway.

  And my here was, again, here, awash in equatorial sunshine and soft air, riding the untroubled waters of El Canal de Santa Cruz, two magnificent frigatebirds moving west on deep, slow wingbeats, and the Beagle bound for a supper of fresh Bacalao (grouper) and langostinos in Puerto Ayora. The episodes that memory had brought forth, of my conversations with the native Hawaiian patriot Noa Emmett Aluli, of purchasing the silver real in Christiansted, of the time Rick told me about the Maori invitation to ease the universal grief of traditional people, and of the honor silence Russell has asked for, to acknowledge the work ordinary laborers had done in their anonymous way, were now situated in the undisturbed present, this moment here, where the world seems more benign and the opportunity to forgive, to accept, floods the heart.

  To recall trouble does not necessarily mean to dwell on what once had happened. The recollections also bring with them the relief that perspective offers.

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  AT THE CORE of Darwin’s idea about evolution is a very simple observation: every living thing has parents.4 The germ cells of each parent carry sets of genes that, though generally the same from one generation to the next, hold out multiple possibilities for the offspring of any given set of parents. The nature of this event, what will actually come of combining these two packets of information, is what scientists call stochastic (i.e., a result that can be approached statistically but that cannot be predicted, i.e., random).

  With the aid of sophisticated tools of observation, geneticists today can identify whole swaths of genetic material in a particular genome—the human genome, for example—and say with some confidence which genes influence which trait in the ontogenic development of a member of a new generation. They can say, in other words, which genes will influence the color of a baby’s eyes and what color they’re likely to be. What they are not able to predict, however, despite their knowing the color of both parents’ eyes, is what the baby will actually look like or—a much more complicated question—how the baby will behave. They can speak with some precision about the first part of the event (the creation of a new person, the beginning of its ontogeny, or growth) but not the second (who the person will be). No one can know what, in fact, is to come.

  Change in the genome of a species over time and the relative quickness with which genetic mutations can start to alter the familiar (and similar) appearance of members of a species are not phenomena easy to characterize. Together with the speed and direction of genetic change taking place because of selective pressures being exerted by an animal’s changing environment (changes in its climate, catastrophic geological events, chronic pollution of its environment, changes in the species it shares an environment with), random genetic change creates a landscape of quicksilver movement for an evolutionary biologist, paleoanthropologists, and other scientists trying to guess where any particular species might be headed, including human beings.

  We know that as one generation succeeds another within a given species, the species changes, usually incrementally but occasionally dramatically. (A species is not so much a permanent thing as a point on the developmental line of that thing through time.) We know that genetic mutation interacts in some way with a species’ environment such that some randomly generated changes in the nucleotides of a gene are reinforced, in order, generally, to perpetuate fitness in a species. But there’s a great difference between the fate of an individual of a particular species and the fate of that species itself. Parents who have great hopes for their own children in an environmentally compromised world may therefore also be parents who despair over the fate of mankind.

  The reason radical changes in the human environment caused by the Industrial Revolution are so anxiety-producing is not that they keep us from predicting a benign future for ourselves. We’ve never been able to do that anyway. It’s that, apparently, major changes in Homo sapiens’s physical environment are occurring with what scientists believe is unprecedented speed. However well individual people might manage in the face of these changes in the decades ahead, the future of the species remains as open a question as it was for all the other hominins we’re related to, none of whom, it’s important to note, are still with us.

  It is characteristic of our age that the urge to commit to the eschatology of a particular organized religion, and the intense critiques of all of organized religions’ eschatologies, are both driven by the same conviction: no one knows where we’re headed. We know only that we will change over time, and that our long history as a relatively stable species (200,000 years or so for anatomically modern man) is no guarantee that these changes will take place slowly, especially in the Anthropocene.

  Darwin receives most of the credit for the way modern people imagine themselves changing through time as a species and for people’s ability to conceive of their phylogenetic ancestors—from australopithecines and several species in the genus Homo through to, probably, Homo heidelbergensis—as being both different from and similar to themselves. In reading The Voyage of the Beagle as a young man, I was struck by two things that I felt shaped the way Darwin came to understand biological evolution. One was the effect of his years-long experience aboard the Beagle. During his time at sea in this two-masted barque, in weathers calm and calamitous, he developed, I thought, a more informed sense of the sheer size of Earth, which he’d had little inkling of as a boy growing up in Shropshire. Each day he spent offshore was one more day in which he stood at the center of almost unlimited space, an expanse of water and sky defined only by the continuous line of the horizon. Every hour at sea, becalmed in the Atlantic’s doldrums or scudding before a quartering wind, the breadth of the ocean he saw and the great reach of the inverted bowl of the sky were in stark contrast to the world Darwin was familiar with as a passenger aboard HMS Beagle, little more than a mote of dust in the vastness between continents. This contrast, day in and day out, between the unknown ocean and the familiar ship, I felt, encouraged Darwin to develop a similar figurative vastness around the idea of evolution just then beginning to mature in his imagination.

  The extent of pelagic space surrounding the Beagle compelled Darwin, I believe, to take what he thought he knew about change in an entirely new direction. The Beagle offered him the comfort and reassurance of a known cultural world: each leech line, halyard, clew line, and sheet on the Beagle was meant to do something specific in a complicated (though not complex) system, and he leaned toward complexity. Each book in the personal library Darwin took aboard the Beagle at Devonport in December 1831 addressed a topic he was already more or less familiar with. His table conversation with Robert FitzRoy, a zealous Christian fundamentalist and the Beagle’s autocratic, mercurial, and very empirically minded master, was predictably orthodox, class sensitive, and reactionary. I have to imagine that Darwin’s glances out the open door of FitzRoy’s cabin, as the inscrutable and protean ocean rolled past each day during their meals together, spoke volumes.

  It struck me as indicative, too, that the subject of the first paper Darwin wrote that was based on his experiences aboard the Beagle concerned the nature of dust blown westward from North Africa on a harmattan wind, dust he found covering the ship’s main deck one morning. Far out to sea, he discovered indisputable evidence of the impermanence of the enduring world.

  The second thing I feel significantly shaped his ideas about biological evolution early on were the three volumes of Charles Lyell’s Principles of Geology. The ramifications suggested by Lyell’s central idea—that Earth was far older than was commonly believed—created a kind of fever in Darwin’s mind. (Darwin received the first volume as a gift from FitzRoy, on their departure. The second and third volumes reached him later in Montevideo and at Port Stanley, respectively, in the Falkland Islands.) In the 1830s, geologists could be roug
hly separated into two camps. Uniformitarians maintained that Earth had changed only gradually through time; catastrophists argued that changes evident on the surface of Earth had occurred suddenly. Each tended to stress the characteristics of physical geology that most strongly supported their views. Uniformitarians pointed to the gradual buildup of sediments on the floors of lakes that give rise to sedimentary rocks, such as sandstone and shale. Catastrophists brought in volcanic eruption and unconformities in layers of rock. What Lyell, a uniformitarian, introduced was a temporal framework within which to reconsider either one of these positions. What he placed before his (for the most part) religiously conservative Christian colleagues was a span of time over which geological processes had been at work that was immense, vast beyond their reckoning. Archbishop Ussher’s six thousand years would not begin to cover it.

  What Lyell offered Darwin was the second part of the context in which to consider biological evolution. With the enormity of space surrounding him almost every day, and with Lyell, who gave him an enormity of time, Darwin was able to see biological evolution as a very long road branching off and unfurling through time, that phenomenon more profound historically and infinitely more complex to him than the impressive but still incidental English machine that he was sailing aboard.

  I can imagine, too, that Darwin sensed yet another stimulus for revising his nascent ideas about biological change through time. It came during the thirty-five days he spent meandering though the islands of Galápagos in 1835 while FitzRoy was making marine soundings. While islands might offer the traveler firm footing and certain concrete realities to deal with—species of plants, layers of sedimentary rock, catchments of freshwater—they are also each circumscribed by a shoreline. In an archipelago, similar islands are almost always visible nearby, across a watery surface that is forever in motion and not so easily characterized by empirical measurements. And to reach any of these other places requires some sort of assistance—a ship or a boat. Darwin must have noticed that certain birds and sea mammals—sea lions and fur seals, for example—actually moved easily among the islands. Later, when he understood for the first time how finches on the various islands differed from one another, he must have considered again what might explain the thing that held all this biology together. What, in other words, was the nature of a biological archipelago—a number of distinctly different but similar things (islands), each individual biome characterized by its own menagerie of life-ecologies but all these biomes subtly related. He must have seen in the connection between biology and geology here, in this microcosm, the adumbration of something quite new.

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  DARWIN CREATED a massive scientific and cultural disturbance in the West with the publication of On the Origin of Species. Theologians viewed his ideas about humankind as a most serious threat to orthodoxy and social order. This Shropshire gentleman, they believed, was arguing that biological change followed no preset course and that it had no purpose other than biological fitness in the moment. Moreover, it was change without a destination. In essence, they saw, he was saying not only that Homo sapiens was not headed in any particular direction as a species (i.e., Homo sapiens was changing over time but not “improving”) but also that humanity had no end point in “perfection.” Further, he was implying there was no hierarchical arrangement of Earthly species, at the apex of which Homo sapiens was to be found. According to one of his most astute biographers, Janet Browne, what most frightened Darwin about his own ideas was not the threat they presented to fundamentalists among the theologians of his day, but that he was implying there was little difference, ultimately, between people and animals. In other words, that humans were not set apart by having “a soul.”

  Darwin’s assertions were shattering to consider because they suggested for some the ultimate meaninglessness of human life. Resistance to his ideas of adaptation and change remains as strong in some quarters today as it was in England in the 1870s. (One of the most peculiar pockets of resistance to the theory of evolution happens to be in Galápagos, where fundamentalist Christians have sought successfully to become certified as official guides. They want to offer visitors alternative ideas about evolution and to emphasize the “special creation” of human life.) Darwin strived to restrict the discussion of his ideas to the province of biology, but of course he was unsuccessful. Atheists, agnostics, political revolutionaries, existentialists, and eventually social Darwinists—all commandeered his insights and took them off in directions Darwin himself probably would never have headed. Darwin was a cogitator, not an agitator, someone better imagined as a philosopher than a provocateur. He was, in fact, the herald of a kind of thinking that wouldn’t come to the fore in another discipline—particle physics—for another forty years. Like Copernicus before him, and like Freud and Jung after him, he changed fundamentally the way we imagine ourselves in the world.

  At the time Darwin was writing, scientists trying to explain the natural world concentrated their research in only two areas, chemistry and physics. Biology was viewed primarily as a descriptive science, a sort of stepsister to the other two types of inquiry, and further, one largely in the hands of gentlemen naturalists, people with nothing more serious on their minds than the twittering of birds and the blooming of roses. What Darwin did was to put biology on a level with physics and chemistry as a path of inquiry into the nature of the natural world. His work in systematics and his theoretical work in evolution took biology into areas of unpredictability and indeterminacy, which physics in fact had been aimed toward since the time of Democritus, and which it finally attained with the development of relativity theory and quantum mechanics. Darwin anticipated Heisenberg’s famous insight, that the kind of indeterminacy that characterizes quantum theory is present in all natural systems. He wasn’t implying that the human effort to achieve, say, moral progress without a map wasn’t possible. He was saying it wasn’t possible to make such a map in the first place.

  Though inclined as a scientist toward the immutability of laws—physics and chemistry had laws: Newton’s first law of motion, say, or Boyle’s laws about the behavior of gases—Darwin was actually giving us reason to consider that biology had no laws. Instead, it had situations, like evolution or parthenogenesis or mitosis. People wonder sometimes whether Darwin might have written in a different way about biological evolution if he’d had Mendel’s “laws” of inheritance to work with. The answer to this is that if Mendel had preceded Darwin, we likely would never have gotten the Darwin who created such an impact. Mendel’s observations about genetic inheritance were not about predictability, as Mendel had hoped. They were about probability, and probability was awaiting a mathematics that would make change more comprehensible.

  When I was seventeen, traveling though Europe with a group of my prep school classmates, I remember emerging from the Uffizi Gallery in Florence one afternoon with my head spinning. The artwork had made a terrific impression on my adolescent and febrile imagination. Trying to walk off the excitement, I ended up on the Ponte Vecchio, staring down at the Arno River. I had a book in my shoulder bag which I’d been trying unsuccessfully to read for several weeks. I was in over my head with it. It was called The Orientation of Animals: Kineses, Taxes, and Compass Reactions. The authors were an entomologist named Gottfried Fraenkel and a zoologist from Sri Lanka, Donald Gunn. Their subject was the way animals, mostly insects, orient themselves in the environments in which they live. Given their needs—to feed and to survive long enough to reproduce—and the quality of their environments, and given a particular moment in time—the temperature and humidity, the season, the angle of the sun—how did they orient themselves in the physical world? The subject was deeply fascinating to me, that animals could be understood in terms of how they adjusted themselves daily in a changeable environment in order to satisfy some utilitarian need. Or simply to please themselves.

  I stood at one of the Ponte Vecchio’s portals between two shops,
struggling with the meaning of some of the technical terms the authors were using, and, not for the last time, closed the book, distracted by the muddy surface of the rain-swollen Arno. And wondering where, in a world of autonomous insects evolving in some South American jungle at that moment, Botticelli’s The Birth of Venus might fit, that painting having left me in a state of wonder as deep as the one Messrs. Fraenkel and Gunn had taken me to.

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  LATE ONE AFTERNOON, our guide aboard the Beagle III, Orlando Falco, offered to take a few of us swimming at Bartolomé, a small island off the east coast of San Salvador. I brought my fins and my mask along, though Orlando said there wouldn’t be much in the way of tropical fish there. The bottom was composed mostly of old lava flows around a few pockets of sand, but there was no coral. The water was so clear I could read the textures of ropy flows of pahoehoe lava twenty feet below the panga. After everyone else had jumped overboard, Orlando took me a little farther offshore, into deeper water, and motioned for me to drop overboard there.