Influenza A viruses continue to be of enormous interest to biomedical researchers and clinicians alike. In addition to the annual influenza epidemics, which have been inferred to cause substantial excess mortality, there is the ever-present threat of a global pandemic due to several features of influenza virus biology. A high mutation rate associated with a [...]
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An interesting hypothesis in the evolutionary genetics of treating infections and cancers is that if the therapeutic agent does not directly target the pathogen or tumor, then the pathogen or tumor will be less likely to evolve resistance to that agent. While early work on inhibitors of angiogenesis as potential cancer therapeutics suggested that [...]
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Both Nature and Science are currently celebrating the 100th anniversary of the birth of an icon of logic, computer science, and mathematical biology: Alan Turing. In reading Andrew Hodges’s spectacular biography of Turing (1983) many years ago I came to appreciate that the subject of the book was both a deeply creative and extraordinarily rigorous [...]
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Natural selection depends on heritable phenotypic variation. The most obvious source of phenotypic variation is genotypic variation. A new study, by Casanueva et al. in Science (2012) suggests that in addition to genotypic variation, variation in life history and stochastic variations in gene expression can substantially affect phenotypic variation. These authors studied mutation penetrance in [...]
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As noted in my last post, the selective advantage of heterozygosity for the sickle allele at the beta-globin locus has been known since Allison’s report in 1954 (Lancet). Nevertheless, a plausible and detailed mechanism to account for the protective effect of an allele that is typically highly deleterious when homozygous has not been forthcoming until [...]
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In previous posts, I discussed, respectively, the use of selection to generate an antibody of potential value in treating influenza A virus infections (1) and the relevance of protein dynamics to the evolution of protein function (2). A recent paper in Science (3) offers evidence suggesting that internal protein dynamics play a crucial role in [...]
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In an 1858 humorous poem The Deacon’s Masterpiece, or the Wondeful One Hoss Shay, Oliver Wendell Holmes Sr. described a carriage so artfully constructed as to have no weakest link. The carriage ran smoothly for exactly a hundred years, and then one day it went to pieces all at once, – All at once, and [...]
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According to both academic lore and history (Paulos, 1985; Ryerson, 2004), the late Sidney Morgenbesser, a professor of philosophy at Columbia and a renowned conversationalist and wit, was once listening to an Oxford colleague, J. L. Austin, lecturing on the philosophy of language. The eminent Professor Austin proceeded to claim that while a double negative [...]
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I recently saw the movie, “The Blind Side,” based on a book of almost the same name (“The Blind Side: Evolution of a Game”) by author, Michael Lewis. The reference to “evolution” in the book title refers to the adaptations necessitated in the (American) game of football on the offensive line, especially at the left tackle [...]
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Posted in Good Questions, Trade-offs on Jun 11th, 2008
The human appendix has long fascinated both biologists and physicians. A recent bout of appendicitis has heightened my interest in this organ and has stimulated me to write about it. Because of its small and variable size, an The human vermiform appendix (image from the Talk Origins Archive; www.talkorigins.org) d its apparent uselessness, Darwin (1871) [...]
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