Showing papers by "John C. Avise published in 1983"

Mitochondrial DNA differentiation during the speciation process in Peromyscus.

Abstract: We address the problem of the possible significance of biological speciation to the magnitude and pattern of divergence of asexually transmitted characters in bisexual species. The empirical data for this report consist of restriction endonuclease site variability in maternally transmitted mitochondrial DNA (mtDNA) isolated from 82 samples of Peromyscus polionotus and P. leucopus collected from major portions of the respective species' ranges. Data are analyzed together with previously published information on P. maniculatus, a sibling species to polionotus. Maps of restriction sites indicate that all of the variation observed can be reasonably attributed to base substitutions leading to loss or gain of particular recognition sites. Magnitude of mtDNA sequence divergence within polionotus (maximum approximately equal to 2%) is roughly comparable to that observed within any of five previously identified mtDNA assemblages in maniculatus. Sequence divergence within leucopus (maximum approximately equal to 4%) is somewhat greater than that within polionotus. Consideration of probable evolutionary links among mtDNA restriction site maps allowed estimation of matriarchal phylogenies within polionotus and leucopus. Clustering algorithms and qualitative Wagner procedures were used to generate phenograms and parsimony networks, respectively, for the between-species comparisons. Three simple graphical models are presented to illustrate some conceivable relationships of mtDNA differentiation to speciation. In theoretical case I, each of two reproductively defined species (A and B) is monophyletic in matriarchal genealogy; the common female ancestor of either species can either predate or postdate the speciation. In case II, neither species is monophyletic in matriarchal genotype. In case III, species B is monophyletic but forms a subclade within A which is thus paraphyletic with respect to B. The empirical results for mtDNA in maniculatus and polionotus appear to conform closely to case III. These theoretical and empirical considerations raise a number of questions about the general relationship of the speciation process to the evolution of uniparentally transmitted traits. Some of these considerations are presented, and it is suggested that the distribution patterns of mtDNA sequence variation within and among extant species should be of considerable relevance to the particular demographies of speciation.

Extensive genetic variation in mitochondrial dna's among geographic populations of the deer mouse, peromyscus maniculatus.

Abstract: Restriction endonucleases have recently permitted the detection of extensive intraspecific mitochondrial DNA (mtDNA) sequence heterogeneity in a number of mammalian species (e.g., Potter et al., 1975; Upholt and Dawid, 1977; Avise et al., 1979b; Brown, 1980; Brown and Simpson, 1981; Ferris et al., 1981). Because mtDNA appears to evolve very rapidly (Brown et al., 1979), and because mtDNA seems to be strictly maternally inherited (Hutchison et al., 1974; Lansman et al., 1983), the molecule has been advocated as a potentially useful marker for estimating matriarchal phylogenies within and among conspecific populations and closely related species (Lansman et al., 1981). To date, however, only a small handful of studies have begun to exploit this potential for natural population analysis (Avise et al., 1979b; Brown and Wright, 1979; Brown, 1980; Brown and Simpson, 1981; Ferris et al., 1981a, 1981b). In the first paper of this series, we included a description of mtDNA restriction fragment divergence among three geographically distant samples of the deer mouse, Peromyscus maniculatus (Avise et al., 1979a). Of particular interest was the observation that samples from Colorado and southern Michigan were very similar in mtDNA sequence (estimated nucleotide divergence, P .005), while a sample from North Carolina was very distinct from these (P .040). Here we greatly extend our survey of the deer mouse by analyzing mtDNA sequence variation in 135 animals collected across much of the vast range of the species in North America. Our procedure has been to map restriction sites recognized by eight endonucleases. The restriction maps permit comparisons of the pattern and character of changes in the mtDNA molecule that have occurred during its evolutionary history in P. maniculatus. Thus the data presented in this paper are of considerable significance to two different but closely interrelated aspects of mtDNA evolution: (1) the ' Number IV in the series, "The use of restriction endonucleases to measure mitochondrial DNA sequence relatedness in natural populations." 2 Current address: Laboratory of Genetics, National Institute of Environmental Health Sciences, Research Triangle Park; North Carolina 27709.

Critical experimental test of the possibility of "paternal leakage" of mitochondrial DNA

Abstract: Most previous data suggesting maternal inheritance of mtDNA have come from single-generation mating experiments, and most of the analytical techniques utilized would not have detected paternal mtDNA molecules in progeny at levels less than about 5%. Long-term mating experiments, in which a fertile female lineage derived from hybridization of two species with distinguishable mtDNAs is backcrossed recurrently to the male parental species, provide an ideal opportunity to assess possible low-level paternal leakage. We have analyzed the 45- and 91-generation backcross progeny of such matings between two species of lepidopteran insects [Heliothis (Noctuidae)], using autoradiographic techniques that can detect rare mtDNA molecules in less than 1 part per 500. The analysis failed to detect any paternal mtDNA and sets an upper limit of paternal leakage at about 1 molecule per 25,000 per generation in this system.

Clonal diversity and population structure in a reef-building coral, acropora cervicornis: self-recognition analysis and demographic interpretation.

Abstract: Description of genetic variation in a population, recognized by Hubby and Lewontin (1966) as providing "the fundamental datum of evolutionary studies," is now routinely accomplished by electrophoretic characterization of allozyme variation and by other molecular techniques. These studies have revealed considerable variation at the molecular level, as well as the structure of this variation within and among populations. Although the value of the molecular approach in population genetics is beyond dispute, there remain interesting aspects of population variation not directly assayable by these methods. Biological self-recognition phenomena, exemplified by self-sterility in flowering plants and immune systems in animals, have been utilized in a population genetic context for only a few species. An analysis of genetic population structure based upon a self-recognition phenomenon requires a relatively straightforward assay incorporating the phenomenon, and an established relationship between the detectable polymorphisms and a more general aspect of population structure. Harberd used a combination of morphological characters and self-sterility relationships to deduce clonal structure in populations of the grasses, Festuca rubra and F. ovina (Harberd, 1961, 1962a) and the clover, Trifolium repens (Harberd, 1962b). In most vertebrate populations nearly every individual possesses a unique histocompatibility type, but some vertebrate population structures have been characterized by a departure from this condition of complete diversification. Kallman (1964) interpreted the occurrence of duplicated histocompatibility types within isolated populations of platyfish as an indication of inbreeding. For populations in which asexual reproduction occurs, some authors (Maslin, 1967; Cuellar, 1976, 1977; Angus and Schultz, 1979; Angus, 1980) have assumed that each clone is distinguished by a unique histocompatibility type, thus equating the diversity of incompatible strains with clonal diversity. In one such study (Angus and Schultz, 1979), a tissue graft analysis applied to populations of the unisexual fish, Poeciliopsis monacha-lucida, resolved more clones than had been detected in an earlier electrophoretic survey (Vrijenhoek et al.,

An empirical evaluation of qualitative Hennigian analyses of protein electrophoretic data.

Abstract: In an empirical evaluation of a qualitative approach to construction of phylogenetic trees from protein-electrophoretic data, we have employed Hennigian cladistic principles to generate molecular trees for waterfowl, rodents, bats, and other phylads. This procedure of tree construction is described in detail. Branching structures of molecular trees produced by three different algorithms were compared against those of “model” classifications previously proposed by other systematists. In each case, the qualitative cladistic trees provided fits to model phylogenies which were strong and as good or better than those resulting from phenetic-clustering or distance-Wagner trees based on manipulation of quantitative values in matrices of genetic distance.

Histocompatibility bioassays of population structure in marine sponges Clonal structure in Verongia longissima and lotrochota birotulata

Abstract: Author(s): Neigel, JE; Avise, JC | Abstract: Clonal population structure in two marine sponges, Verongia longissimia and lotrochota birotulata, was examined with a self-recognition bioassay. The bioassay consists of grafts of branch segments between conspecific individuals. Results were consistent with the operational properties expected of a precise histocompatibility system. Autografts exhibited acceptance responses; grafts between individuals separated by large distances exhibited rejection responses; Individuals were not limited to a single mode of response at one time; and all identity relationships were transitive. Clonal population structure was assessed by examining the relationship between graft response and donor-to-recipient distance, and by actually mapping the distributions of particular clones. Clones of lotrochota birotulata were usually restricted to single coral heads or small patch reefs (1-3 m diameter). For Verongla longissima, which can grow directly upon the coral rubble surrounding coral heads and patch reefs, individual clones often occupied larger areas (up to 10 m diameter). The spatial patterns of clonal distributions are readily interpreted as consequences of the particular demographies and habitat specificitles of these two species. / 1983, American Genetic Association.