Leftist radicalism and an uneven passage through ROTC were minor deflections from my chosen trajectory. My resolve to be a biologist was reinforced when I discovered the ideal social environment for developing a scientist—or at least one of several possible ideals. It is the same as for a political revolutionary. Start with a circle of ambitious students who talk and work together and conspire against their elders in order to make their way into a particular discipline. They can be as few as two or as many as five; more than five makes the unit unstable. Give them an exciting new idea that can transform the discipline and with which they can advance their ambitions: let them believe that they own a central truth shared by few others and therefore a piece of the future. Add a distant authority figure, in this case a scientist who has written a revolutionary text, or at least a circle of older revolutionaries who have generated the accepted canon. The farther away these icons are from their acolytes, the better. At midcentury, Europe was best of all. French and German pedants, especially if their texts are hard to translate (and therefore require exegesis by English-speaking disciples) are especially potent. Bring on a local role model, an older man or woman who promotes The Idea and embodies in his character and working habits the ideals of the youthful discipline.
The circle I joined in my sophomore year, though all older than I by two to seven years, were also novices, committed naturalists, and ambitious. They included future successful academics: George Ball from Detroit, later to become professor of entomology at the University of Alberta; Herbert Boschung, a fellow native Alabamian who was to remain at the university first as professor and subsequently as director of the Alabama State Natural History Museum; Hugh Rawls, whose love of mollusks led to a professorship in Illinois; and Barry Valentine, a New Yorker who became a professor of zoology and entomology at Ohio State University.
Our mentor in this formulaic mix was Ralph Chermock, newly arrived from Cornell University as an assistant professor. A relative of Erich Tschermak von Seysenegg, one of the three rediscoverers of the Mendelian laws of heredity, he was a highly competent specialist in butterfly classification and deeply committed to research on evolutionary biology. At thirty, Chermock was physically impressive, an amateur boxer with a compact gymnast’s body and thick arms, who occasionally performed one-arm pushups on his office floor to intimidate his followers, but also a tense man who chain-smoked and often snorted and giggled when he laughed. He had the disconcerting habit of listening intently to everything you had to tell him, head cocked and wearing an inviting but quizzical smile, like a psychiatrist or a skeptical job interviewer.
Perhaps I overinterpret Chermock’s demeanor from his particular reaction to me. On arriving at the university in 1947 he immediately spotted me as a youngster turning spoiled and overconfident from too much praise. An adjustment was in order. He scandalized me by giving me an A - instead of A in a course on evolutionary theory when I was convinced I had done brilliantly—at least until thirty years later, when I reread my final examination paper. In any case he took every opportunity to grind my ego down to size. When I completed a careful laboratory study of prey selection in the trapjawed ant Strumigenys louisianae, using a “cafeteria” technique I had invented myself, and showed him the article I had written on my findings, his response was muted. He gravely informed me that I could never publish the article until I had confirmed the laboratory data by going back into the field and actually finding the same prey captured and dead in undisturbed Strumigenys nests. I knew it would be like searching for a needle in a haystack, but out I went, day after day, locating these elusive little ants and carefully opening their nests until finally I discovered one with freshly caught prey that were still intact enough to be identified before the voracious larvae had eaten them; and Chermock relented. The several best teachers of my life, including Chermock, have been those who told me that my very best was not yet good enough.
Ball and Valentine had come to Alabama explicitly to work with Ralph Chermock. With him they brought the Cornell mystique, the reputation of an entomology department whose history extended back to the great nineteenth-century pioneer John Henry Comstock, and whose reputation for total dedication to insect research at the highest professional level was and remains internationally respected. Awed by the legends, I felt myself to be in the best of company.
The prophets of the Chermock circle were the architects of the Modern Synthesis of evolutionary theory. All were, in 1947, men of middle age who worked in prestigious places like Columbia, the University of Chicago, and New York’s American Museum of Natural History. The sacred text of the Chermock circle was Ernst Mayr’s 1942 work Systematics and the Origin of Species. Mayr was the curator of birds at the American Museum, but his training had been in Germany, a source of added cachet. The revolution in systematics and biogeography that Mayr promulgated was spreading worldwide, but especially in England and the United States, the national strongholds of Darwinian evolutionary theory.
Bear with me while I explain the reason for the extraordinary impact of the new Darwinian movement. By 1920, just a quarter-century before I encountered it as a student, evolutionary biology had dissolved into a jumble of natural history observations, with its best theory consisting of a few rules and geographic trends mounted upon statistical correlations. The principle of natural selection, the core of the Darwinian theory, was itself in doubt. Geneticists thought that evolution might proceed not so much by incremental episodes of natural selection (acting upon continuously varying traits such as size, instinct, and digestion) as by mutations that change heredity in discontinuous steps. In retrospect it seems obvious that both propositions had to be true. Variation, we now understand very well, arises by mutations and also by recombinations of mutations during sexual reproduction; the changes can be large or small in effect; and natural selection—differential survival and reproduction—determines which mutations and combinations survive and reproduce by virtue of the traits they prescribe in such properties as size, instinct, and digestion.
This synthetic view is essentially the Darwinian theory of natural selection with mutating genes added. The close connection to Darwinism is why the modern theory came to be called Neo-Darwinism or, just as often, the Modern Synthesis. In the 1920s and early 1930s a group of population geneticists, most prominently Sergei Chetverikov of Russia, Sewall Wright of the United States, and J. B. S. Haldane and Ronald A. Fisher of England, used mathematical models to demonstrate that one gene form created by mutation can replace another throughout a population even if its advantage in survival and reproduction is quite small, say 1 or 2 percent. In theory at least, the substitution can occur rapidly, with most of it completed in as few as ten generations. Such microevolution, entailing one or a few genes at a time, can accumulate to become macroevolution, producing whole new structures such as eyes and wings. It can also cause the splitting of species into two or more daughter species, a process that is the fount of higher-level biodiversity.
The Modern Synthesis reconciled the originally differing worldviews of the geneticists and naturalists. It empowered scientists in both disciplines to examine the entire evolutionary cavalcade as an extension of Mendelian heredity and, later, to add the refinements of genetics brought by molecular biology. The natural history phase of the Modern Synthesis followed genetics and natural selection theory. If there was any single moment of birth, it was the publication in 1937 of Theodosius Dobzhansky’s landmark Genetics and the Origin of Species. For the first time, new data from the field and laboratory defined the differences among species and races with precision, illuminating the nature of variation within populations in chromosomes and genes, and the steps of microevolution. Evolution seemed firmly grounded in genetics, at least to the following extent: nothing the geneticists could say by the late 1940s, when I came along as a student, seemed likely to overturn the Modern Synthesis. Only a complete surprise, something major and out of the blue, could accomplish that. To this day nothing so radical has occurred, although ma
ny an ambitious biologist has tried to play the role of revolutionary.
The naturalists were given a hunting license, and for the Chermock circle Mayr’s Systematics and the Origin of Species, following upon Dobzhansky’s book, was the hunter’s vade mecum. From Mayr we learned how to define species as biological units. With the help of his written word we pondered the exceptions to be expected and the processes by which races evolved into species. We acquired a clearer, more logical way to think about classification by using the phylogenetic method. This system measures differences between species by the amount of evolution that has occurred since they split apart.
Also in our armamentarium was George Gaylord Simpson’s Tempo and Mode in Evolution, published in 1944. The great paleontologist argued that the fossil record is consistent with the evidences of ongoing evolution seen in living species. And finally, in 1950, botany entered the mainstream with the publication of Ledyard Stebbins’ Variation and Evolution in Plants.
We thus were equipped with the texts of radical authority. We also had field guides and our own previously acquired expertise: fishes, amphibians, and reptiles for Boschung; mollusks for Rawls; beetles for Ball and Valentine; and ants for me. And providence shone bright on all of us together: Valentine had an automobile. We were scientifically licensed hunters, with the means to roam an ecologically diverse state that had to that time been only partly explored by naturalists.
Chermock encouraged us to collect not only our favored organisms but also amphibians and reptiles for the University of Alabama collection. On weekends and holidays we struck out across the state, to the farthest corners and back and forth. We pulled the car over to roadsides and clambered down into bay-gum swamps, hiked along muddy stream banks, and worked in and out of remote hillside forests. On rainy spring nights we drove along deserted rural back roads, falling silent to listen for choruses of frogs. Sometimes I sat on the front fender of the car as Rawls or Valentine drove slowly. Perched that way, with my left arm curled around a headlight and a collecting jar held in my right hand, I watched for frogs and snakes spotlighted by the high beams of the car. When one was sighted the driver stopped the car, and I dashed ahead to bottle the specimen. On other nights we walked the streets of Tuscaloosa, observing and collecting insects attracted to the lights of storefronts and service stations. During these expeditions I soaked up new information on dryinids, perlids, limulodids, entomobryomorphs, plethodontids, lithobiids, sphingids, libelludids, and so on and on deep into the heart of biodiversity. Chermock was unimpressed by our growing expertise. He told us, half seriously, that we could not call ourselves biologists until we knew the names of 10,000 kinds of organisms. I doubt that he could have passed the test himself, but it didn’t matter. Hyperbole from the chief kept our juices flowing.
By the age of eighteen I had been converted to scientific professionalism. Barely out of my Boy Scout years, I was back on the trail of merit badges, this time through research, discovery, and publication. I came to understand that science is a social activity. Previously I had spent most of my time in natural history to learn about wild creatures and to enjoy personal adventure. I didn’t care much what others thought of my activity. Now, as Alfred North Whitehead once said of scientists generally, I did not discover in order to learn; I learned in order to discover. My private pleasure was now tinged with social value. I came routinely to ask: What have I acquired in my studies that is new not just for me but for science as a whole?
The poorly explored Alabama environment offered the Chermock circle boundless opportunity for discovery even with minimal training. One night we drove slowly from the central part of the state into the Florida panhandle, stopping the car frequently to listen to the songs of chorus frogs mating in the accumulated rainwater of roadside ditches. (For a close approximation of a chorus frog call, run the edge of your fingernail along the fine teeth of a pocket comb.) We were searching for the zone where the northern race Pseudacris nigrita triseriata, which sings with one trill pattern, meets and interbreeds with the southern race, Pseudacris nigrita nigrita, which sings with a different pattern. Near dawn we encountered the changeover close to the Florida border, and then it proved to be very abrupt. We reasoned that the two forms are actually reproductively isolated species, not interbreeding races, and deserved their formal distinction as Pseudacris triseriata and Pseudacris nigrita. Research by later specialists proved us right.
At another time, wading far up the underground stream of a cave in northern Alabama, we discovered a new kind of blind white shrimp. And again: in mixed hardwood and pine forests, Barry Valentine and I collected the first Alabama specimens of the rare insect order Zoraptera, and soon afterward published our records in an entomological journal. Occasionally I worked alone, an old habit. While digging into soil on the fringes of a swamp near Tuscaloosa, I discovered a new species of a pretty little ant with dark-brown body and yellow legs and described it as Leptothorax tuscaloosae.
Scientific discovery at this elementary level was all so easy, all such fun. I could not understand why most of the other students at the university did not also aspire to be biologists.
Meanwhile I developed a strong new research interest in the imported fire ant, which I had first observed in Mobile in 1942. The notorious pest species was beginning to spread out of the city and into the fields and woodlands of the rural countryside. In 1948 Bill Ziebach, the “Outdoors” editor of the Mobile Press Register, began a series of articles on the threat by the ant to crops and wildlife. He consulted me on the species and quoted me in the paper. As a result, in early 1949 the Alabama Department of Conservation asked me to conduct a study of the ant and evaluate its impact on the environment. I took leave from the university for the spring term to begin, at the age of nineteen, a four-month stint as entomologist, my first position as a professional scientist. I was joined by James Eads, another biologist, like my other companions a war veteran in his mid-twenties and, most crucially again, owner of a car. Jim and I crisscrossed southwestern Alabama and the western counties of the Florida panhandle, mapping the expanding semicircular range of the ant. We dug up colonies to analyze nest structure, explored fields for crop damage, and interviewed farmers. In July we submitted a fifty-three-page analysis to the Department of Conservation office in Montgomery titled “A Report on the Imported Fire Ant Solenopsis saevissima var. richteri Forel in Alabama.” It contained original findings on the ant still in use today, including the rate of spread (five miles a year along all borders), the partial elimination of native fire ant species, and documentation of moderate crop damage caused by direct consumption of seeds and seedlings.
How this notorious insect got its common name is itself a story worth telling. Up to the time of our first meeting with state officials in Montgomery, the species was called the Argentine fire ant, in recognition of its presumed native origins (it is now known to occur widely through northern Argentina as far as the Paraguayan border). Someone in the Department of Conservation suggested that the name might prove offensive to Argentinians; we already had too many German cockroaches, English sparrows, and the like. We should change it, he said, while we had time. Someone else, I can’t remember who, suggested the imported fire ant. That name was used in our report and subsequently by the media and in scientific literature.
In the year following, while working on my master’s degree at the University of Alabama, I intensified my studies of the imported fire ant. Eads and I, along with Marion Smith at the National Museum, had observed that workers of the species belonging to different colonies vary in color from dark brown to light reddish brown. I noticed further that the light workers were smaller, and that their colonies appeared to be displacing those of the dark workers. By 1949 the dark form was limited mostly to peripheral areas in Alabama and Mississippi. It had disappeared entirely from Mobile, its point of origin. I set out to test experimentally whether the two forms were genetically distinct. One method I invented was to introduce light queens into dark colonies and observe
the color of their offspring reared in a socially altered environment. The color remained true to their mother queen, providing evidence—but not definitive proof—that the difference between light and dark was hereditary.
In the course of my switching experiments I discovered that when more than one queen was introduced into a new colony at the same time, the workers executed all but one by stinging and dismembering them. They never made the mistake of eliminating the final queen, which would have destroyed the colony’s ability to produce more workers. This result foreshadowed the discovery, by other entomologists thirty years later, that the workers are able to discriminate among many queens and select the healthiest and most fecund.
In a history of the imported fire ant I published later, in 1951, I considered the color forms to be varieties of the same species. In 1972 William Buren, after an exhaustive new study, confirmed my general findings but elevated the light form to full species rank. He gave it the name Solenopsis invicta, meaning the “unconquered” Solenopsis. In 1972 the ant was spreading throughout the southern United States in the teeth of intense efforts and the expenditure of over $100 million to stop it. In a widely quoted interview at the time I summed up the futility of the enterprise in a phrase: the fire ant eradication program, I said, is the Vietnam of entomology.
Naturalist 25th Anniversary Edition Page 10