Asa Gray

American botanist

• Born: November 18, 1810
• Birthplace: Sauquoit, New York
• Died: January 30, 1888
• Place of death: Cambridge, Massachusetts

The leading botanical taxonomist in nineteenth century United States and the founder of the discipline of plant geography, Gray was the first advocate of Darwinian evolution in the United States.

Early Life

The son of Moses Gray, a tanner, and Roxana Howard Gray (New Englanders who had migrated to upstate New York after the Revolutionary War), Asa Gray was born in upstate New York and educated at local schools and academies. He entered the College of Physicians and Surgeons of the Western District of New York in 1826. Alternating attendance at the lectures at the medical school with apprenticeship with practicing physicians, Gray received his medical degree in January, 1831.

Slight, short, and clean-shaven until his middle age, Gray was physically agile and appeared ever-youthful. This physical agility was matched by his mental quickness. Complementing these traits was a self-assuredness that led him to abandon medical practice in 1832 to follow his dream of becoming a botanist.

Life’s Work

Gray’s interest in botany had been sparked by James Hadley, one of the faculty at the College of Physicians and Surgeons, but his real mentor was John Torrey, one of the outstanding American botanists. After a tryout in 1832, Torrey hired Gray the following year to collect specimens for him. Ultimately, Gray moved into the Torrey home and became Torrey’s collaborator on his Flora of North America (1838-1843).

Finding employment as a scientist during the 1830’s was not easy. For the first few years after he rejected a medical career, Gray supported himself through part-time teaching and library jobs. In 1836, he was selected as botanist on the United States Exploring Expedition but resigned the position in 1838, before the expedition ever sailed, disgusted by the delays that had plagued the venture. Instead, he became professor of botany (the first such professorship in the United States) at the University of Michigan, spending the next year in Europe purchasing books and equipment for the university. The university’s financial problems resulted, however, in the suspension of his salary in 1840, before he had ever taught a class.

Not until April, 1842, with his appointment as Fisher Professor of Natural History at Harvard University, with responsibility for teaching botany and maintaining the botanical gardens, did Gray obtain a stable and permanent institutional home. He remained at Harvard (which also indirectly supplied him with his wife, Jane Lathrop Loring, the daughter of a leading Boston lawyer who was a member of the Harvard Corporation) for the rest of his life.

Manifest Destiny helped shape the contours of Gray’s scientific career: Overseas exploration and domestic reconnaissance and surveying during the two decades before the Civil War had resulted in a huge flow eastward of botanical specimens gathered by army engineers, naval explorers, and collectors accompanying the expeditions. Gray spent most of his professional life worrying about the nomenclature and taxonomy of these plants. Through either his own research or the coordination of the activities of other botanists, he was responsible for the description of flora gathered from Japan to Mexico.

By the 1850’s, Gray was clearly the leading botanist in the United States. He was the cement that held together a huge network of amateur collectors. His publications included the Manual of the Botany of the Northern United States (1848) and extremely popular textbooks for college, high school, and elementary school students. A frequent visitor to Europe, he was well known in international scientific circles.

The opportunity for Gray’s greatest contribution to science came about because of his international reputation, but his connection with this flow of specimens enabled him to exploit fully the opportunity. Charles Darwin had written him in April, 1855, inquiring about the geographical distribution of Alpine plants in the United States. In response, Gray produced a statistical analysis of the flora of the northern United States, drawing on his wide knowledge of the botany of the Northern Hemisphere. This in turn encouraged Darwin in 1857 to let Gray in on his great secret—the theory of evolution.

At this point, Gray had in hand an extensive collection from Japan, gathered by Charles Wright during the North Pacific Exploring Expedition, as well as smaller collections from Matthew C. Perry’s expedition, which opened up Japan. Gray discerned that the flora of Japan was much more similar to that of eastern North America than western North America or Europe. He rejected the possibility of separate creation and, applying Darwin’s ideas, proposed instead that the similarities reflect the evolution of the flora from common ancestry under similar conditions. A single flora, Gray theorized, had stretched round the earth before the Ice Age; changing geological conditions resulted in the differences in Northern Hemispheric flora.

This public endorsement of Darwin in early 1859, the first in the United States, was followed by many others. Gray quickly became the leading American spokesperson for Darwin’s theory, and he negotiated the American publishing contract for On the Origin of Species by Means of Natural Selection (1859). Moreover, the review of this work in the American Journal of Science, the leading American scientific journal of the day, was written by Gray. Time and again he debated the leading anti-evolutionist in the American scientific community, the Swiss-born Louis Agassiz, director of Harvard’s Museum of Comparative Zoology. In 1860, in a series of articles in the Atlantic Monthly, Gray defended Darwin from critics who charged that the theory of evolution was hostile to religion, taking a position on the compatibility of Darwinian evolution with theism that the author of the theory himself was unable ultimately to accept.

After his retirement from teaching in 1873, Gray continued his research and field trips. He spent six triumphant months in Europe in 1887, returning to the United States in October. A month later, he was taken ill and died in his home in Cambridge on January 30, 1888. He left behind the Harvard Botanic Garden, the Gray Herbarium, and a generation of botanists and collectors for whom he had provided training, guidance, and assistance.

Significance

Asa Gray was fortunate to be a botanist in the United States at a time when the expansionist drive of the nation resulted in its soldiers and sailors crisscrossing the North American continent and the Pacific Ocean. Describing the botanical fruits of these exploring and surveying expeditions was Gray’s lifelong work. His skill helped set American botany on a par with its European counterparts. Prodded by Charles Darwin, he asked some important questions about plant distribution that led to the development of a new scientific field and further evidence for the evolutionary thought of Darwin.

Gray’s greatest impact on American society, however, was as the defender of Darwin’s theory of evolution. Gray, a member of the First Congregation Church of Cambridge, understood that if evolution was to be accepted by the deeply religious American scientific community of the mid-nineteenth century, it would have to be reconciled with a belief in the existence of God. Gray believed that Darwin’s theory, whatever its scientific merits, had to be defended from accusations of atheism. His solution was to suggest that the Creator intervened by limiting or directing variations. Darwin could not accept such an interpretation, however, and Gray’s vision died with him. If Darwin had made another choice, the intellectual, cultural, and philosophical history of the West might have taken a course much different from that which it subsequently followed.

Bibliography

Dupree, A. Hunter. Asa Gray: 1810-1888. Cambridge, Mass.: Belknap Press of Harvard University Press, 1968. The standard biography, well documented, interpretive, and accurate. Views Gray within the context of the social and intellectual history of the United States.

Evans, Howard Ensign. Pioneer Naturalists: The Discovery and Naming of North American Plants and Animals. Drawings by Michael G. Kippenhan. New York: Holt, 1993. Provides information about more than 100 people who lent their names to North American plants and animals. Includes information about Gray and other prominent naturalists.

Eyde, Richard H. “Expedition Botany: The Making of a New Profession.” In Magnificent Voyagers: The U.S. Exploring Expedition, 1838-1842, edited by Herman J. Viola and Carolyn Margolis. Washington, D.C.: Smithsonian Institution Press, 1985. Discusses the problems surrounding the botanical activities of the expedition.

Fry, C. George, and Jon Paul Fry. Congregationalists and Evolution: Asa Gray and Louis Agassiz. Lanham, Md.: University Press of America, 1989. Compares the lives and philosophies of Gray and his Harvard colleague, zoologist Louis Agassiz, focusing on their dispute over Darwin’s theory of evolution and their membership in the Congregationalist Church.

Goetzmann, William H. Exploration and Empire: The Explorer and the Scientist in the Winning of the American West. New York: Alfred A. Knopf, 1966. A well-researched history of American exploration in the nineteenth century and the scientific discoveries that were its by-product. Although Gray is mentioned only briefly, this book describes the context of much of his scientific efforts.

Gray, Asa. Darwiniana. Edited by A. Hunter Dupree. Cambridge, Mass.: Belknap Press of Harvard University Press, 1963. A collection of Gray’s essays on evolution, first published in 1876. Essential for understanding Gray’s attempt to reconcile evolution and religion.

‗‗‗‗‗‗‗. The Letters of Asa Gray. Edited by Jane Loring Gray. 2 vols. Boston: Houghton Mifflin, 1893. This collection, edited by Gray’s widow, includes Gray’s autobiography.

Keeney, Elizabeth. The Botanizers: Amateur Scientists in Nineteenth-Century America. Chapel Hill: University of North Carolina Press, 1992. In the nineteenth century, tens of thousands of amateur botanists (or “botanizers”) collected plant samples, exchanged specimens, and corresponded with expert botanists. Using popular magazines, textbooks, letters, diaries, and other contemporary sources, Keeney traces the rise and fall of botany as a popular recreational science. Includes information about Gray’s participation in the movement.

Lurie, Edward. Louis Agassiz: A Life in Science. Chicago: University of Chicago Press, 1960. The essential biography of Darwin’s chief American scientific opponent.

Rodgers, Andrew Denny, III. American Botany, 1873-1892: Decades of Transition. Princeton, N.J.: Princeton University Press, 1944. Discusses the evolution of American botany from a descriptive to an experimental science and Gray’s role in that transition.

‗‗‗‗‗‗‗. John Torrey: A Story of North American Botany. Princeton, N.J.: Princeton University Press, 1942. A scholarly, although somewhat dated biography of Gray’s mentor. Provides an excellent account of Torrey’s scientific accomplishments and his role in developing American botany.