Contemporary systematic philosophies
01 Nov 1970-Annual Review of Ecology, Evolution, and Systematics (Annual Reviews 4139 El Camino Way, P.O. Box 10139, Palo Alto, CA 94303-0139, USA)-Vol. 1, Iss: 1, pp 396-440
TL;DR: This phenetic school of taxonomy had its origins in a series of papers in which several workers attempted to quantify the processes and procedures used by taxonomists to classify organisms, of special interest was the process of weighting.
Abstract: During the past decade, taxonomists have been engaged in a controversy over the proper methods and foundations of biological classification. Although methodologically inclined taxonomists had been discussing these issues for years, the emergence of an energetic and vocal school of taxonomists, headed by Sokal and Sneath, increased the urgency of the dispute. This phenetic school of taxonomy had its origins in a series of papers in which several workers attempted to quantify the processes and procedures used by taxonomists to classify organisms. Of special interest was the process of weighting. These early papers give the impression that the primary motivation for the movement was the desire to make taxonomy sufficiently explicit and precise to permit quantification and, hence, the utilization of computers as aids in classification [22, 23, 41, 91, 106, 107, 111, 112], The initial conclusion that these authors seemed to come to was that taxonomy, as it was then being practiced, was too vague, intuitive, and diffuse to permit quantification. Hence, the procedures and foundations of biological classification had to be changed.
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01 Jan 1945
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TL;DR: A survey of the literature indicates that when such arrangements are made, they usually correspond very closely to previously recognized relationships of various species groups based on classical systematic criteria, which makes it clear that electrophoretic techniques will provide an extremely valuable tool for systematists.
Abstract: Avise, John C. (Department of Genetics, University of California, Davis, California 95616) 1975. Systematic value of electrophoretic data. Syst. Zool. 23:465-481.-Two consistent observations from recent multi-locus electrophoretic studies are: (1) levels of genic similarity between conspecific populations appear very high (populations nearly identical in allelic content at 85 percent or more of their loci) and (2) genic similarities between different, even very closely related species, are generally much lower and more widely dispersed (congeneric species pairs often completely distinct at one-fifth to four-fifths of their loci). These observations have valuable implications regarding the practical utility of electrophoresis: (1) one or a few samples often yield adequate data for the description of an entire species for systematic purposes and (2) closely related species may be arranged according to percentages of shared alleles or genotypes. A survey of the literature indicates that when such arrangements are made, they usually correspond very closely to previously recognized relationships of various species groups based on classical systematic criteria. This observation, coupled with several theoretical advantages of the study of allozymes, makes it clear that electrophoretic techniques will provide an extremely valuable tool for systematists. [Electrophoresis; genetics; systematics.] Electrophoretic techniques were first used by Tiselius (1937; cited by Brewer, 1970) to distinguish multiple fractions of serum proteins migrating through solution under the influence of an electric current. During the next 25 years, advances in electrophoretic methodology and knowledge centered on three fronts: (1) improvements in types of supporting media including the development of starch gels (Smithies, 1955) which are widely used today; (2) the application of histochemical staining methods (Hunter and Markert, 1957), which allowed analysis of electrophoretic variation in enzymatic proteins; and (3) the demonstration that much of the variation was inherited in simple Mendelian fashion. Prior to 1963, most studies described variation in single proteins, but by the mid 1960's, electrophoretic techniques were sufficiently refined to permit examinations of large numbers of different proteins in the same organisms (Hubby, 1963; Hubby and Throckmorton, 1965; Hubby and Lewontin, 1966; Johnson et al., 1966; Lewontin and Hubby, 1966; Harris, 1966). These multi-loci studies were the prototypes for a profitable new method of analysis of levels of genic variability and population structure (review by Gottlieb, 1971). Ironically, some of their findings may also have had an initially retarding influence on the evaluation of electrophoretic data in systematics because, although it was immediately recognized that a quantification of allozyme differences between populations (based on allele or genotype frequencies) might offer potentially valuable information for systematics (Hubby and Throckmorton, 1965), other allozymic results stimulated far greater interest. The disclosure of very high levels of genic variability in natural populations was in apparent conflict with classical population genetic models of balanced load, and hence generated great controversy. Researchers turned their attention to the question of whether most allozymes were maintained by natural selection or were selectively neutral (Proc. VI Berkeley Symp., 1972). Thus, even by 1970, a major review of electrophoretic literature included almost no discussion of uses of electrophoretic data in systematics, other than for description and identification of species (Manwell and Baker, 1970). Today, the selectionist versus
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TL;DR: A new classification scheme is presented, built on the work of Porter and Abell, as a first step toward developing an “optimal” business strategy classification system.
Abstract: Porter's (1980) and Abell's (1980) attempts to classify business strategies have several fundamental limitations After discussing the objectives and attributes of “scientific” classification systems, this article presents a new classification scheme, built on the work of Porter and Abell, as a first step toward developing an “optimal” business strategy classification system.
323 citations
TL;DR: It is concluded that phylogeny-driven microbial genome sequencing projects such as the Genomic Encyclopaedia of Archaea and Bacteria (GEBA) project are likely to rectify the situation of microbial systematics and genomics being reconciled.
279 citations
01 Jan 1993
TL;DR: Baboon diversity is used to explore some aspects of species definition and diagnosis, without attempting a comprehensive revision of the group or an exhaustive exploration of the species concept.
Abstract: The baboons of the genus Papio [excluding the gelada (Theropithecus) and (pace Delson, 1975), the mandrills, and drills (Mandrillus)] comprise a cluster of para-patric populations spread across most of the Ethiopian faunal zone. The present paper uses baboon diversity to explore some aspects of species definition and diagnosis, without attempting a comprehensive revision of the group or an exhaustive exploration of the species concept. The baboons are well suited to this purpose, because the various phenotypically distinct “forms” (which I call subspecies) have some but not all of the attributes commonly used to define one or another variant of the species concept. Another advantage is their quasi-continuous distribution, mostly undivided by extrinsic barriers that would avoid the problem of delineating natural units yet including some populations that are geographically isolated but not phenetically distinct, which illustrate the problems of definition raised by extrinsic isolation.
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TL;DR: Page 108, last line of text, for "P/P″" read "P′/ P″."
Abstract: Page 108, last line of text, for "P/P″" read "P′/P″."
Page 120, last line, for "δ v " read "δ y ."
Page 123, line 10, for "4Nn" read "4Nu."
Page 125, line 1, for "q" read "q."
Page 126, line 12, for "q" read "q."
Page 135, line 5 from bottom, for "y4Nsq" read "e4Nsq."
Page 141, lines 8
7,850 citations