A Brief History of Evolution at Indiana University
Indiana University (IU) was founded in 1820, making it the oldest state university west of the Allegheny Mountains. Evolution entered the curricula in 1864 with the hiring of Richard Owens, the commander of the 60th Indiana Volunteers during the Civil War. Owens had a medical degree, but his real interests were in geology. Thus, it is perhaps unsurprising that his lectures in the natural sciences had a strong evolutionary flavor.
Owens retired in 1879 and was replaced by David Starr Jordan, an extraordinary researcher, teacher, and administrator. Jordan was a student of fishes, but his work impacted biology more broadly. He championed Darwinian evolution, and his 1888 monograph titled, "Darwinism, a brief account of Darwinian theory of the origin of species," catalyzed the acceptance of evolution by the American natural science community. As president of IU and later Stanford University, Jordan also encouraged and facilitated the shift of biological research from an emphasis on natural history to one on experimentalism. Finally, his massive research program on the fishes of the world greatly enriched the zoological literature of the period. Jordan's achievements have recently been honored by the establishment of the David Starr Jordan Prize, an international prize that rewards groundbreaking work by young scientists in the disciplines to which Jordan contributed--evolution, ecology, and population or organismal biology.
When Jordan left to become the first president of Stanford University, he was replaced by Carl Eigenmann. Eigenmann mirrored Jordan both in his focus on fishes, and in his broader interests in ecology, development, and evolutionary biology. Eigenmann was particularly interested in biogeography, and he and his students studied the relative importance of ecology and history in explaining the geographic distribution of fishes. In 1894, Eigenmann became Dean of the Graduate School and over the next 33 years influenced the hiring of a broad array of faculty, including two with interests in evolutionary biology: the gall-wasp systematist, Alfred Kinsey and fruit-fly cytologist Fernandus Payne.
Although Kinsey is primarily recognized for his work on human sexual behavior, his impact on systematic and evolutionary biology was surprisingly large as well. His studies of individual and geographic variation, as well as his insistence that all aspects of an organism be studied, were unique at the time, but later became standard practice in biosystematics. Likewise, his pioneering introduction of statistical methods to taxonomy foreshadowed "numerical taxonomy," an approach which dominated systematics in the 1960s. Even after he became famous for his sex research, he always maintained that he was a taxonomist applying taxonomic methods to an important social phenomenon.
Although a taxonomist first, Kinsey's writings contained a substantial evolutionary component as well. For example, he described adaptive radiation in insular gall wasps, commented on the origin and definition of species, and theorized on the origin of higher taxa. He was generally bemused that his ideas on the origin of species and higher taxa were more readily accepted by evolutionary geneticists than taxonomists.
Unlike Kinsey, who was raised and educated in New England, Fernandus Payne was an Indiana farm boy. After completing his undergraduate degree in zoology at IU, he moved to Columbia University for graduate work. As a doctoral student, Payne had the distinction of introducing the fruit fly from Bloomington to Columbia, where it was adopted as an experimental animal by T. H. Morgan. In terms of research, Payne is probably best known for his paper "Sixty-nine generations in the dark," which remains a classic disproof of Lamarckian evolution.
Payne was appointed chairman of zoology in 1927, a position he held until 1948. During that period and the decade that followed, the genetics and evolution group at IU probably reached its zenith. Noteworthy faculty (all National Academy of Science members) included protozoologist Tracy Sonneborn, Nobel Laureate geneticist Hermann Muller, plant geneticist Ralph Cleland, plant biosystematist Charles Heiser, and Nobel Laureate microbial geneticist, Salvador Luria. In addition, Nobel Laureate James Watson completed his doctoral work at IU with Luria.
Of this group, Muller undoubtedly had the greatest impact on evolutionary biology. Like Payne, Muller received his doctoral degree under the direction of T. H. Morgan at Columbia University. Muller made numerous contributions to basic genetics and more broadly to evolutionary theory. He was an uncompromising Darwinist, and his work on gene mutations can be viewed as providing a mechanism for Darwinian variation. In particular, he showed that genes reproduce their variations; i.e., mutations change the function of genes, but not their capacity for replication. Muller also demonstrated that most mutations were deleterious and recognized that sexual recombination served to combine adaptive gene combinations and purge maladaptive ones. Because most of the slightly deleterious genes were nearly recessive, Muller realized that they would accumulate in populations and reduce fitness, a phenomenon he referred to as genetic load.
In addition to his studies of mutation and its role in evolution, Muller made pioneering contributions to our understanding of adaptive evolution and speciation. Early in his career, his recognition of the role of modifier and major genes in controlling quantitative traits helped restore Darwin's theory of natural selection by gradual change. He also independently derived a simple epistatic model for the evolution of hybrid sterility or inviability, which is now commonly referred to as the Bateson-Dobzhansky-Muller model.
Muller's botanical colleagues, Cleland and Heiser, also made substantial contributions to evolutionary biology. Cleland was a leading student of chromosomal structural heterozygosity. His elegant studies of the cytogenetics and evolution of permanent structural heterozygosity in Oenothera helped make it the best understood example of this phenomenon in plants. More generally, his detailed investigations of the evolutionary factors and pathways responsible for diversification in Oenothera were unique at that time, and his work provided the first convincing evidence for homoploid hybrid speciation in nature.
Like Cleland, Heiser's early work also concerned the role of hybridization in evolution. During the 1940s and 1950s, introgressive hybridization was viewed as a major contributor to adaptive evolution, and intermediate morphologies were often interpreted to result from hybridization. Working with members of the sunflower genus, Helianthus, Heiser demonstrated how experimental crosses and cytogenetic work were necessary to rigorously test hypotheses of natural hybridization and introgression. Heiser, however, is probably best known for his studies of the biosystematics and evolution of domesticated plants and their wild relatives, including sunflowers, peppers, bottle gourds, nightshades, naranjilla, chenopodium, sumpweed, and locusts. He identified the possible wild progenitors of many of these cultivars, clarified their systematics, and provided insight into the probable early stages of their domestication. His many books in this area, including The Gourd Book, The Sunflower, Of Plants and People, and Seed to Civilization, represent easily readable and highly entertaining discussions of the evolution of domesticated plants. Heiser, a former president of the Society for the Study of Evolution, continues to work on domesticated plants as a distinguished emeritus professor at IU.
The work of Sonneborn and Luria, although eminent scientists, was not as directly related to evolutionary biology as that of Muller, Cleland and Heiser. Nonetheless, Sonneborn did lay the groundwork for evolutionary studies in protozoans by working out so much of the basic biology and genetics. His work on the role of nuclear and cytoplasmic factors in inheritance and the "killer" trait in Paramecium inspired studies of the origin of cell organelles. Sonneborn also discussed the species problem in Protozoa, described mating system evolution in this group, and published the first nucleotide sequence of a gene. Luria is best known for his Nobel Prize winning studies of the genetics of bacteria and bacterial viruses.
The modern era (1960-present) of evolutionary biology at Indiana University has been characterized by growth in both the number and diversity of faculty that study evolution. As a result, IU has become an increasingly attractive location for evolutionary studies, and our evolution group is one of the strongest in the nation. Details concerning our current faculty and degree programs can be found elsewhere on the Department of Biology website.