Van Valen, Leigh: An evolutionary biologist who came up with the model of the Red Queen -- the living chess piece that Alice encounters in Through the Looking Glass who must keep running as fast as she can to stay in the same place -- as a metaphor to explain evolutionary patterns. His studies involve genetics and systematics, and involve a wide range of topics, including the evolution of biotas and of mammals.
variance: A measure of how variable a set of numbers are. Technically, it is the sum of squared deviations from the mean divided by (n-1) (the number of numbers in the sample minus one). Thus, to find the variance of the set of numbers 4, 6,and 8, we first calculate the mean, which is 6. We then sum the squared deviations from the mean (4 - 6)2 + (6 - 6)2 + (8 - 6)2, which comes to 8, and divide by (n-1) (which is 2 in this case). The variance of the three numbers is8/2 = 4. The more variable the set of numbers, the higher the variance. The variance of a set of identical numbers (such as 6, 6, and 6) is zero.
Vermeij, Geerat J.: Biologist at the Center for Population Biology of th eUniversity of California, Davis, and author of Privileged Hands: A Scientific Life. Vermeij, blind since age 3, combines autobiography and description of the evolutionary "arms race" between intertidal predator and prey species. Wider research interests include economic relationships between organisms and ecosystems and their implications for human organisms.
vertebrates: The group (specifically, a subphylum) of animals, descended from a common ancestor, that share the derived character of an internal skeleton made of bone or cartilage.
vestigial: Any structures that have been greatly reduced in size and function over evolutionary time to the extent that they now appear to have little or no current function.
virulence: The disease-producing ability of a microorganism.
virus: A kind of intracellular parasite that can replicate only inside a living cell. In its dispersal stage between host cells, a virus consists of nucleic acid that codes for a small number of genes, surrounded by a protein coat. (Less formally, according to Medawar's definition, a virus is "a piece of bad news wrapped in a protein.")
vitamin A: A member of a chemically heterogeneous class of organic compounds that are essential, in small quantities, for life.
Von Mutius, Erika: A pediatrician and allergist, Dr. von Mutius's research interests include the epidemiology of childhood asthma and allergies with a focus on environmental predictors and gene-environment interactions.
Vrijenhoek, Robert: A senior scientist in the areas of evolutionary biology, marine biology, and conservation, Vrijenhoek studies the ecological and evolutionary consequences of genetic diversity in animals. His research efforts have focused on the evolutionary and ecological consequences of sexual and asexual reproduction in Mexican poeciliid fish (genus Poeciliopsis), as well as invertebrates in deep-sea hydrothermal vents.
Wake, David: A professor in the Department of Integrative Biology at the University of California, Berkeley, Dr. Wake's research emphasizes analysis of evolutionary patterns and the processes that produce them, ranging from functional morphology to evolutionary genetics and population ecology. Amphibians and reptiles are the focus of his work.
Wallace, Alfred Russel: A British naturalist and contemporary of Charles Darwin. Wallace conducted research on the Amazon River and studied the zoological differences between animal species of Asia and Australia, developing a theory of evolution similar to Darwin's.
Ward, Peter Douglas: Professor of geological sciences at the University of Washington in Seattle, where he is also adjunct professor of zoology and of astronomy. Author of several books on biodiversity and the fossil record, Including Rivers in Time: The Search for Clues to Earth's Mass Extinctions and Rare Earth: Why Complex Life is Uncommon in the Universe (with Donald Brownlee).He is the principal investigator for the University of Washington's portion of the NASA Astrobiology Institute.
Wegener, Alfred: A German climatologist and geophysicist whose book, The Origins of Continents and Oceans, was the first to propose the concept of continental drift (the forerunner to the theory of plate tectonics), as well as to suggest a supercontinent called Pangaea, which Wegener suggested had fragmented into the continents as we know them today. His ideas remained controversial until the1960s, when they became widely accepted as new evidence led to the development of the concept of plate tectonics.
White, Tim: A paleoanthropologist with University of California, Berkeley's Laboratory for Human Evolutionary Studies, White is known for his meticulous fieldwork and analysis investigating early hominid skeletal biology, environmental context, and behavior. With an international team of colleagues, he discovered and named Ardipithecus ramidus and Australopithecus garhi.
wild type: The genotype or phenotype, out of a set of genotypes or phenotypes of a species, that is found in nature. The expression is mainly used in lab genetics to distinguish rare mutant forms of a species from the lab stock of normal individuals.
Wilford, John Noble: A New York Times reporter and winner of two Pulitzer Prizes for his national reporting of science topics, and for his work on the Challenger explosion and the aftermath. While at the Times he served as science correspondent, assistant national news editor, and director of science news.
Wilson, E.O.: A biologist and professor at Harvard University since 1955. Wilson has won two Pulitzer Prizes for his books On Human Nature and The Ants, and has received numerous honors for his research and conservation efforts.