On September 5, 1955, I flew to New York. The last four hours up to Boston by train, eased only slightly by an anesthetic reading and rereading of a copy of that week’s Life magazine, were the longest of my life. Finally, clad in khaki and heavy boots, crew-cut, twenty pounds underweight, and tinted faint yellow from the antimalarial drug quinacrine, I fell into Renee’s arms. I came home innocent of hula hoops, Davy Crockett, Tommy Manville’s ninth divorce, and other Western Hemispheric events of 1955. I had not heard Vice President Richard Nixon say, “Sincerity is the quality that comes through on television.” I was ignorant of the latest in men’s leisure clothing, which, should you wish to learn or be reminded, consisted of cotton jersey pullovers, bateau necklines, and moccasin slip-ons worn in chaste combinations to create a European effect. American culture had begun to fade for me around the edges in the ten months of my absence. I began quickly to recover, however, with the help of ten-cent hamburgers at the White Tower and hours of serious television watching.
Six weeks later Renee and I were married in Boston’s St. Cecilia Church. We moved to Holden Green, university housing on the Cambridge-Somerville line that seemed to be the starting point of most young Harvard couples. There were young Holden Greeners on their way up and out and older Holden Greeners who apparently wanted to stay there and at Harvard forever.
The following winter I was offered an assistant professorship in Harvard’s Department of Biology. My main function would be to assist William H. (“Cap”) Weston, an elderly professor and fungus expert, in the creation of a new beginning biology course for nonscience students. The department chairman, Frank Carpenter, who had previously served as my doctoral adviser, cautioned me that the appointment would be for five years only. After that I had a distant chance of further employment, but the position was not tenure track. Would I be interested just the same? I had already sent letters of inquiry to thirty other prospective employers and gleaned offers from the University of Florida and the University of Michigan, both tenure track. Then, as now for most colleges and universities, this meant that all I had to do was perform well for the first few years to be guaranteed a lifetime position.
The impermanence of the Harvard position did not faze me. I was young, only twenty-six, and wanted the added time there to settle in a world-class collection and library and to expand my research program. I accepted Harvard’s offer and set out to plan my first lectures.
Partway into the first year, however, my nerve began to fail. Like all assistant professors at the great university, I felt disposable. And obviously, I was disposable. With Renee’s assistance, I made plans to find a new position long before the end of my five-year term put me on the street. Then providentially, in the spring of 1958, with more than three years to go, Stanford University offered me an associate professorship with lifetime tenure as part of the package. The invitation came out of the blue in a letter from Victor Twitty, chairman of the Department of Biology, flat and definitive, prefaced by no tentative inquiry, and conditional upon no visit and seminar. Twitty said in effect: Here it is; will you join us?
Soon afterward Frederick Terman, dean of the Stanford faculty, came to visit me in my office in the Biological Laboratories. He was accompanied by an older gentleman whom he introduced as Wallace Sterling.
When the two were seated, I turned to Sterling. “Are you with Stanford, too?”
Terman answered for him: “Yes, he’s the president.”
Leaving me time to regain my composure, the two men went on smoothly to explain that the biology faculty hoped that I would come to Palo Alto to build a new program in entomology. The incumbent professor, a specialist on scale insects, was retiring. I listened with intense excitement. Stanford was the Harvard of the West, and California was the golden state of the 1950s. Come to this land of opportunity, they said, and help us to grow. I knew that others were responding to the call. Earlier that year Time had reported a westward surge of scientists and other academics from the older eastern universities.
Renee and I were thrilled by Stanford’s commitment. I was really wanted for my special skills in entomology and for my myrmecophilia, the love of ants! The salary was also good for the times, $7,500 a year, and Stanford would assist us in buying a house, a policy unheard of at Harvard. The next morning I told Carpenter that I was going to Stanford. Thank you, I said, for all you have done. He said, Wait a few weeks before making a firm commitment. Let’s see what Harvard can do. Over the next two months the biology faculty and McGeorge Bundy, dean of the Faculty of Arts and Sciences, moved to review my status and decide whether to match the offer from Stanford. As I waited I tossed the matter around in my mind. To the present day this is how Harvard makes most offers of tenure to its own young faculty. It reacts to outside threat, and even then turns down a majority of the hopefuls. The process seems more ponderous than anything west of the Vatican, usually taking a year or more to complete. But I was favored by an accelerated schedule. I received the offer from Mac Bundy, and I decided.
Nowadays on freezing January mornings in Cambridge, as I pick my way across Kandinsky landscapes of snow painted with automobile smudge and dog urine, I remind myself that the New England winter is a hard but fair price to pay to work closely with the best collection of ants in the world. Thirty-five years after accepting Harvard’s tenure offer, having reached the same age as Cap Weston when he walked with me into the lecture room of Allston Burr Hall that first September morning, I still teach a large class in beginning biology for nonmajors. My contentment with this repetitious schedule does not rise from the comfortable stagnation of the tenured academic. Rather, it exists because I find Harvard undergraduates wonderfully talented, and because each year’s contact with them renews me. Most share my own restlessness and optimistic rationalism. We work each other up into enthusiastic conversation. The nonscientists in particular are a prime investment. I know they will carry with them into great ventures, in law, government, business, and art, the commitments they first acquire in the university’s hothouse environment, and a few (it has happened) will convert to biology. I speak to these students as intellectual equals, keeping in the back of my mind their prospective if not immediate attainment of that status. In 1992 the Committee on Undergraduate Education, consisting of undergraduate students, awarded me the Levenson Prize, as outstanding tenured teacher in the college. But I have another, more selfish reason for lecturing on biology to nonscientists. The bourgeois life of the college teacher, if one’s schedule is not too crowded, frees the mind for creative work.
By 1958 I had temporarily forsaken field biology to press research in the laboratory and museum. My central aim was the classification and analysis of the ants of New Guinea and the surrounding regions of tropical Asia, Australia, and the South Pacific. I had embarked on a bread-and-butter task, of a largely descriptive nature. It was time-consuming, tedious, fact-centered, and, for this combination of reasons, virtuous in my own mind.
So let me digress for a moment to explain the special satisfaction of taxonomy. It is a craft and a body of knowledge that builds in the head of a biologist only through years of monkish labor. The taxonomist enjoys the status of mechanic and engineer among biologists. He knows that without the expert knowledge accumulated through his brand of specialized study, much of biological research would soon come to a halt. Only a specialist expert enough to recognize the species chosen for study (“Ah, that is a carabid beetle of the genus Scarites”) can unlock all that is already known about it in the literature. From journal pages and museum specimens he is able to go promptly from the already discovered to the exhilarating unknown. If a biologist does not have the name of the species, he is lost. As the Chinese say, the first step to wisdom is getting the right name.
There is much more. A skilled taxonomist is not just a museum labeler. He is a world authority, often the world authority since there are so few taxonomists, on the group he has chosen. He is steward and spokesman for a hundred, or a thousand, species. Other scientis
ts come to him to seek entry to his taxon—sharks, rotifers, soldier flies, weevils, conifers, dinoflagellates, cyanobacteria, and so on down the long roster comprising over a million species. He knows not only the classification but also the anatomy, physiology, behavior, biogeography, and evolutionary history of the group, in fine detail both published and unpublished. In conversation he will speak as follows: “Come to think of it, there is an enchytraeid I ran into in Honduras with a reddish color, and that just might be the invertebrate hemoglobin you’re looking for.” Or, “No, no, the main center of that particular moth family is the temperate forests of southern Chile. Those species haven’t been worked on yet, but there is a big collection in the National Museum made by the Hensley expedition in 1923. Let’s check it out.” No CD-ROM, no encyclopedia can replace the taxonomic expert. Once, after receiving an award in Japan for such studies, I had the additional honor of spending an evening in conversation with Emperor Akihito, a noted specialist on the taxonomy of gobiid fishes. Soon I fell into a comfortable routine of listening to him speak about gobies and Japan’s endangered fish species, while he and his family asked me questions about ants. It was like a Harvard seminar. At times I almost (but never completely) forgot with whom I was speaking.
In 1958, sitting in my office on the first floor of the Biological Laboratories, occasionally glancing out the window past the monumental bronze statues of the Indian white rhinoceros, I felt on temporarily safe professional ground returning to this kind of enterprise. It guaranteed a stream of tangible results, the kind for which grants-in-aid and other professional emoluments are awarded. At the age of twenty-nine, I had fifty-five technical articles published or in press. Being thoroughly professional in attitude by that time, I knew that every young scientist needs such proof of productivity. Otherwise the National Science Foundation and J. S. Guggenheim Selection Committee will wave his grant applications aside. But if truly creative he does not always hug the coast. He gambles repeatedly on risky projects, stays alert and aggressive, ready to move whenever a long shot shows a hint of promise.
What, then, were my gambles? Highly diverse in nature, they came to me as unplanned products of pedestrian daily research. During my accumulation of facts about ant biology, vaporous notions—constructs, definitions, inchoate patterns (the perfect phrase escapes me)—drifted in and out of my mind like Celtic fog. My daydreams were mostly about the origins of biological diversity. Most took coherent form, only to prove marginal or unattractive, then to fade and disappear. A few went on to gain robust life in the course of my daily reverie. They then turned into narratives, which I began to repeat to myself like stories. I prepared to speak about the matter to others. I imagined how the narrative would look in print, how it might sound in a lecture before a skeptical audience. I rehearsed, edited, and performed in silence. I was a storyteller, sorting and arranging pieces of nonfiction, dreaming in order to fill in the gaps. Then I tried the performance before a real audience.
One of my first constructions was a critique of subspecies, the formal category of race used universally in biological classifications. My coauthor in this endeavor was William L. Brown, seven years my senior, who had enticed me to come to Harvard as a graduate student. During 1952 we met almost daily at lunch to gossip and mull over issues in evolutionary biology. Brown, I soon learned from his pungent remarks, was a scientific curmudgeon. He seemed happiest when he could sprinkle doubt on the reputation of a reigning academic pooh-bah. He tended to divide all scientific ideas into two piles: those he embraced passionately and those he ridiculed. Passionate he was (and remains), but also thoroughly professional. And proletarian in spirit, a hater of pomposity and pretense. Grinning impishly, he would hold up an imaginary “phony meter” when certain faculty notables walked nearby, and take a reading: Red zone! Off the scale! In other lives he would have been the first sergeant who wisecracks about the foibles of the company commander, or the engineer, oil-streaked in the bowels of the plant, who makes up for and grumbles about the incompetence of management. He enjoyed having a beer, or two or three, with working-class stiffs at a nearby bar after a day in the Museum of Comparative Zoology. He was annoyed with me for not joining him. “Can’t completely trust someone who doesn’t like beer.” It seems never to have occurred to him that he was himself a member of the ruling class. But no matter; his animadversions were usually on target. Management was incompetent, a lot of the time. This year, as we began collaborating, he had been roused by the subspecies.
It was a subject deserving close inspection. Everywhere taxonomists were treating the subspecies as an objective category and one of the key steps of evolution. Consider their logic: species are divided into subspecies, which we must assume to be real and objective because given enough time they evolve into species, which are real and objective. Subspecies were (and still are) given formal latinized names by taxonomists. The bald eagle Haliaeetus leucocephalus, for example, is a species divided by taxonomists into two such races, the southern bald eagle Haliaeetus leucocephalus leucocephalus and the northern bald eagle Haliaeetus leucocephalus washingtoniensis.
For reasons not immediately clear to Brown and me, subspecies seemed insubstantial and arbitrary. We set out to conduct a critical review of the premises behind their recognition, by looking at real cases. The foundations proved even weaker than we had imagined. We discovered that the geographic limits of subspecies are often hard or impossible to draw, because the traits used to define them vary in a discordant pattern. The nature of the discordance can be most immediately understood with an imaginary but typical example: color in a butterfly species varies east to west, size decreases from north to south, and an extra band appears on the hind wing in a few localities near the center. And so on for any number of traits the taxonomist might choose from an almost endless list available for classification. It follows that the identity of the subspecies into which the butterfly species is divided depends on the traits chosen to define them. Pick color, and you have two east-west races. Pick color plus size, and four races in a quadrant come into existence. Add the hind-wing band, and the number of races can double again. Hence the subspecies are arbitrary. In 1953 we published a report recommending that subspecies not be given formal names.* We argued that the geographic variation is real all right but should instead be analyzed trait by trait. It is more informative to focus on the traits and not on the subspecies that might be concocted from them.
Our critique of the subspecies triggered a tempest of controversy in the journals of systematic biology. When the debate subsided several years later, opinion had shifted to our side. Fewer triple-name races were formally described thereafter, and emphasis was increasingly placed on the properties of independently varying traits. Nevertheless, I realize now that Brown and I overstated our case in 1953. Some populations can be defined clearly with sets of genetic traits that do change in a concordant, not a discordant manner. Furthermore, the subspecies category is often a convenient shorthand for alluding to important populations even when their genetic status is ambiguous. What, for example, is the Florida panther? It is a subspecies, a nearly vanished remnant of a series of populations once widespread across the United States, now further altered by hybridization with panthers of South American origin released to the wild in south Florida. Biologists rightly speak of the Florida population in a way that calls attention to its genetic distinctness, using one sharp phrase: the Florida subspecies (or race, meaning the same thing) of Felis concolor.
Soon afterward Brown and I made a second conceptual discovery, this one unfettered by controversy. We found a new phenomenon in biodiversity, which we came to call character displacement. The process is the exact opposite of hybridization. In hybridization, two species exchange genes where they meet, and as a result become overall more similar. In character displacement two species spring apart where they meet, like particles with the same charge. I first encountered the mysterious effect in the ant genus Lasius, which I had chosen as the subject of my Ph.D. dissert
ation. During our lunchtime dialogues Brown and I explored the possible causes and searched the literature for a similar pattern in other kinds of organisms.
We learned that the British ornithologist David Lack had already delineated character displacement in his 1947 study of Darwin’s finches on the Galápagos Islands. In the 1970s and 1980s Peter Grant of Princeton University, his wife, Rosemary, and their students were to work out displacement in exquisite detail through a lengthy field study of the same finches in the Galápagos. Thus this little group of birds has been favored by three of the best field studies in the history of evolutionary biology: those by Darwin, Lack, and the Grants, respectively. The principal contribution that Brown and I made in our 1956 report was to show that the repellant effect is widespread among animals and is caused, according to the species pair considered, by either competition or the active avoidance of hybridization.* We brought character displacement to prominence in biology and gave it the name now in general use.
Character displacement, we also realized, is one means by which species can be packed together more tightly in ecosystems. The evolution of greater differences between species reduces the chance that one of them will erase the other through competition or hybridization. The better the mutual adjustment that avoids competition and hybridization, the more species that can live together indefinitely; hence the richer will be the biodiversity, as an outcome of evolution in the community as a whole. In 1959 Evelyn Hutchinson of Yale University, the doyen of ecology, used our presentation of character displacement as a key point in his highly influential article, “Homage to Santa Rosalia, or Why Are There So Many Kinds of Animals?” The question he posed in this title became the entree for ecologists who later tried to analyze the basis of biodiversity in more quantitative terms. They asked, Why are there a certain number of butterfly species in Florida, and not some other? of snakes in Trinidad, of marsupials in Australia? Just posing such questions presaged the effort to understand more deeply the causes of species formation and extinction, which by the 1980s was to become a prominent social issue in biology.
Naturalist 25th Anniversary Edition Page 18