Leigh Van Valen (August 12, 1935 – October 16, 2010) was a U.S.

evolutionary biologist Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life for ...

. At the time of his death, he was professor emeritus in the Department of Ecology and Evolution at the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

Research and interests

Amongst other work, Van Valen's proposed "Law of Extinction", known as Van Valen's law, drew upon the apparent constant probability (as opposed to rate) of extinction in families of related organisms, based on data compiled from existing literature on the duration of tens of thousands of genera throughout the fossil record. Van Valen proposed the

Red Queen Hypothesis The Red Queen hypothesis is a hypothesis in evolutionary biology proposed in 1973, that species must constantly adapt, evolve, and proliferate in order to survive while pitted against ever-evolving opposing species. The hypothesis was intended ...

(1973), as an explanatory tangent to the Law of Extinction. The Red Queen Hypothesis captures the idea that there is a constant 'arms race' between co-evolving species. Its name is a reference to the Red Queen's race in Lewis Carroll's ''

Through the Looking-Glass ''Through the Looking-Glass, and What Alice Found There'' (also known as ''Alice Through the Looking-Glass'' or simply ''Through the Looking-Glass'') is a novel published on 27 December 1871 (though indicated as 1872) by Lewis Carroll and the ...

'', in which the chess board moves such that Alice must continue running just to stay in the same place. Van Valen also defined the Ecological Species Concept in 1976, in contrast to

Ernst Mayr Ernst Walter Mayr (; 5 July 1904 – 3 February 2005) was one of the 20th century's leading evolutionary biologists. He was also a renowned taxonomist, tropical explorer, ornithologist, philosopher of biology, and historian of science. His ...

Biological Species Concept The species problem is the set of questions that arises when biologists attempt to define what a species is. Such a definition is called a species concept; there are at least 26 recognized species concepts. A species concept that works well for se ...

. In 1991, he proposed that

HeLa HeLa (; also Hela or hela) is an immortalized cell line used in scientific research. It is the oldest and most commonly used human cell line. The line is derived from cervical cancer cells taken on February 8, 1951, named after Henrietta ...

cells be defined as a new species, which was named ''Helacyton gartleri''. Van Valen originated the concept of

fuzzy sets In mathematics, fuzzy sets (a.k.a. uncertain sets) are sets whose elements have degrees of membership. Fuzzy sets were introduced independently by Lotfi A. Zadeh in 1965 as an extension of the classical notion of set. At the same time, defined ...

, prior to the formalization of this concept by L.A. Zadeh. He was the editor of the journal ''Evolutionary Theory,'' which he printed on simple paper stock under the motto, "Substance over form." He was also interested in fields outside biology, including

measure theory In mathematics, the concept of a measure is a generalization and formalization of geometrical measures (length, area, volume) and other common notions, such as mass and probability of events. These seemingly distinct concepts have many simila ...

probability theory Probability theory is the branch of mathematics concerned with probability. Although there are several different probability interpretations, probability theory treats the concept in a rigorous mathematical manner by expressing it through a set ...

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from prem ...

thermodynamics Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws ...

epistemology Epistemology (; ), or the theory of knowledge, is the branch of philosophy concerned with knowledge. Epistemology is considered a major subfield of philosophy, along with other major subfields such as ethics, logic, and metaphysics. Epi ...

and the

philosophy of science Philosophy of science is a branch of philosophy concerned with the foundations, methods, and implications of science. The central questions of this study concern what qualifies as science, the reliability of scientific theories, and the ultim ...

. As a biologist, Van Valen considered the role of zoological and botanical gardens, in a world with a degrading natural environment, to be essential for the safeguard of endangered flora and fauna.

Biography

Leigh Van Valen was born on Aug. 12, 1935, in Albany, NY and was chosen "most academic" in the first grade. He earned a zoology and botany degree at age 20 in 1955 from

Miami University Miami University (informally Miami of Ohio or simply Miami) is a public research university in Oxford, Ohio. The university was founded in 1809, making it the second-oldest university in Ohio (behind Ohio University, founded in 1804) and the ...

Ohio Ohio () is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Of the List of states and territories of the United States, fifty U.S. states, it is the List of U.S. states and territories by area, 34th-l ...

. As a graduate student at Columbia, he studied under George Gaylord Simpson and Theodosius Dobzhansky, both giants in honing the synthetic theory of evolution, which melded Darwin's ideas about evolution with Mendel's on genetics. Van Valen met and married Phebe May Hoff while they were both doctoral students in biology at Columbia University. They had two children, girls Katrina and Diana. They divorced in 1984 after a long and friendly separation. Van Valen then married Virginia Maiorana, and eventually separated from that relationship as well. His last great love, with whom he was engaged to be married, was Towako Katsuno, a Japanese professor of Geriatric Nursing. They met when she came to Chicago to do her PhD. Leigh Van Valen died on October 16, 2010 of

pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severit ...

at St. Mary of Nazareth Hospital Center in

Chicago, Illinois (''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = Country , subdivision_name ...

. Van Valen had been hospitalized for more than three months from a rare form of fungal pneumonia, complicated by a long-standing but slowly progressing form of

leukemia Leukemia ( also spelled leukaemia and pronounced ) is a group of blood cancers that usually begin in the bone marrow and result in high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or ...

.Family history, Leigh's daughter Katrina Van Valen.

Van Valen's description of his work

On the University of Chicago website for the Committee on Conceptual and Historical Studies of Science, Van Valen had written and posted this about himself:

Publications

Van Valen's publications include: * "Ecological species, multispecies, and oaks" (1976), Taxon, 25:233–239. * "

, a new microbial species". With Virginia C. Maiorana (1991). Evolutionary Theory, 10:71–74. * "The extinction of the multituberculates", Systematic Zoology 15 (1966), 261¬278 (with R.E. Sloan). * "Selection in natural populations 7, New York babies (Fetal Life Study)", Annals of Human Genetics 31 (1967), 109–121 (with G.W. Mellen). * "The origins of inversion polymorphisms", American Naturalist 102 (1968), 5–24 (with R. Levins). * "A new evolutionary law", Evolutionary Theory 1 (1973), 1–30. * "Brain size and intelligence in man", American Journal of Physical Anthropology 40 (1974), 417–423. * "Multivariate structural statistics in natural history", Journal of Theoretical Biology 45 (1974), 235–247. * "Group selection, sex, and fossils", Evolution 29 (1975), 87–94. * "Individualistic classes", Philosophy of Science 43 (1977), 539–541. * "The Archaebacteria and eukaryotic origins", Nature 287 (1980), 248–250 (with V.C. Maiorana). * "Why misunderstand the evolutionary half of biology?" in E. Saarinen, ed., Conceptual Issues in Ecology, Reidel, 1982, 323–343. * "Homology and causes", Journal of Morphology 173 (1982), 305–312. * "Species, sets, and the derivative nature of philosophy", Biology and Philosophy 3 (1988), 49–66. * "Biotal evolution: a manifesto", Evolutionary Theory 10 (1991), 1–13. * "The origin of the plesiadapid primates and the nature of Purgatorius", Evolutionary Monographs 15 (1994), 1–79. * "The last third of Mendel's paper", Evolutionary Theory 12 (2001), 99–100. * "The evolution of menopause", Evolutionary Theory 12 (2003), 131–153. * "The statistics of variation", in: Variation (B. Hallgrímsson & B. Hall, ed.), Elsevier Academic Press (2005), 29–47. * "How ubiquitous is adaptation? A critique of the epiphenomenist program", Biology and Philosophy 24 (2009), 267–280.

References

External links

University of Chicago homepageWeb page dedicated to Leigh Van Valen
{{DEFAULTSORT:Van Valen, Leigh Evolutionary biologists American biologists 1935 births University of Chicago faculty 2010 deaths Deaths from leukemia Deaths from cancer in Illinois Academic journal editors