Francisco J. Ayala | Biography

Well into the age of genetic engineering and cloning, the Darwinian debate continues, and few other scientists have done such concentrated work in elucidating the mechanism of evolution--and thus shedding light on that debate--as Francisco J. Ayala. Ayala has made vital contributions to the modern theory of evolution, both by theory and experiment, examining the rates and patterns of molecular evolution, the causes of genetic polymorphism (the ability of two or more distinct forms of an organism to coexist in the same interbreeding population) or gene mutation (changes in the hereditary material) in one species, the importance of natural selection versus random selection, as well as the role that reproductive isolation and environment play on population growth. Additionally, Ayala has been a major voice in the philosophical and ethical issues related to the study of human evolution.

Francisco Jose Ayala was born in Madrid, Spain, the son of a businessman, Francisco Ayala, and of Soledad (Pereda) Ayala. His early education was attained in the city of his birth, and in 1955, Ayala graduated with a B.S. from the University of Madrid. Six years later, after studies at the University of Salamanca, Ayala came to the United States to study at Columbia University in New York. He earned his M.A. there in 1963 and his Ph.D. in genetics the next year. Following graduation, Ayala remained on the east coast, in and around New York, first as a research associate at Rockefeller University (1964-1965), and then as an assistant professor both at Providence College, Providence Rhode Island (1965-1967), and at Rockefeller University (1967-1971). During these years Ayala worked on an experimental model to relate the amount of genetic polymorphism to the rate of evolutionary change, using principally the Drosophila, or various species of the fruit fly as the control subject. His resulting publications established a new understanding of the mechanics of adaptation in evolution. It was also during the late 1960s that Ayala met his future wife, Mary Henderson. They were married on May 27, 1968 and have two children. Ayala became a naturalized United States citizen in 1971.

It was also in 1971 that Ayala accepted a post as assistant professor of genetics at the University of California at Davis, and was made full professor three years later. He remained at Davis until 1987, when he became a distinguished professor of biological science at the University of California at Irvine. His work since the late 1960s has been focused in three primary areas: the process of geographic speciation or divergence of species; the study of adaptive significance of genetic variation in various populations; and the process of molecular evolution. In the first of these, Ayala and his researchers studied three groups of species from various parts of the world and were able--by using molecular techniques--to ascertain how much genetic change occurred during the several stages of speciation. In studying adaptive significance, Ayala and his colleagues have been able to demonstrate how environmental factors such as food supply, density of population, and temperature affect the selection of genetic variants. Finally, in the field of molecular evolution, Ayala's studies of DNA cloning have broken new ground and challenged old models of evolutionary change.

Ayala's research in the 1980s with various disease-causing protozoa has also had direct impact on medicine. Various parasitic protozoa affect millions of people worldwide, and Ayala discovered that many of these organisms have a clonal--reproduce by cloning--rather than a sexual population structure. This discovery was vital to the production of vaccines that fight such organisms.

For his work in genetics and evolution, Ayala has been honored with many awards: the Medal of the College of France, 1979; the W. E. Key Award from the American Genetics Association, 1985; and the Scientific Freedom and Responsibility Award of the American Association for the Advancement of Science, 1987, among others. A fellow of scientific societies around the world and the holder of numerous honorary doctorates, Ayala is also a frequent spokesperson in the debate between evolution and creationism, and has published widely on the humanistic aspects of science.