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Genetics and Genomics Commons

Open Access. Powered by Scholars. Published by Universities.®

1998

Zoology

Articles 1 - 4 of 4

Full-Text Articles in Genetics and Genomics

Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi Jan 1998

Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi

Dissertations, Theses, and Masters Projects

Blue marlin diversity was assessed at mtDNA, scnDNA, microsatellite DNA, and allozyme molecular markers. Hierarchical analysis of molecular variance (AMOVA) revealed that most genetic variation was maintained within populations, with a non-significant fraction attributable to variation among temporal replicates and between locations within oceans. In contrast, inter-ocean divergence was highly significant for a majority of loci within each marker class. Previous studies of mitochondrial DNA (mtDNA; n = 104) genetic variation within the blue marlin revealed two distinct clades of haplotypes, one of which was present only in the Atlantic (the 'Atlantic clade'), at a frequency of 40% &(F\sb{lcub}st{rcub}& = …


The Phylogeny Of Coleoid Cephalopods Inferred From Molecular Evolutionary Analyses Of The Cytochrome C Oxidase I, Muscle Actin, And Cytoplasmic Actin Genes, David Bruno Carlini Jan 1998

The Phylogeny Of Coleoid Cephalopods Inferred From Molecular Evolutionary Analyses Of The Cytochrome C Oxidase I, Muscle Actin, And Cytoplasmic Actin Genes, David Bruno Carlini

Dissertations, Theses, and Masters Projects

Although the fossil record of early cephalopods is rich and demonstrates the dominance of the group in Paleozoic times, the mainly soft-bodied coleoids (Cephalopoda: Coleoidea) are poorly represented. Therefore, little is known of the evolutionary history of coleoids through paleontology and current classifications of the subclass are based primarily on the morphology of extant representatives. A molecular phylogenetic analysis of the Coleoidea was therefore warranted. Phylogenetic relationships within the Coleoidea were constructed using molecular sequence data from one mitochondrial and two nuclear genes: cytochrome c oxidase I (COI) and two unlinked actin genes (Actin I and Actin II, respectively). A …


Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford Jan 1998

Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford

Dissertations, Theses, and Masters Projects

Phylogenetic and historical biogeographic hypotheses were explored for three groups of teleost fishes that are hypothesized to share a common biogeographic track. Distributed across the eastern Pacific/eastern Atlantic (EP/EA) biogeographic track of Rosen (1975) are the Scomberomorus regalis (Scombridae), Strongylura marina (Belonidae) and Hyporhamphus unifasciatus (Hemiramphidae) species groups comprised of one eastern Atlantic; three, three and four western Atlantic; and two, two and four eastern Pacific species, respectively, for each group. In addition, two species in the Strongylura marina and Hyporhamphus unifasciatus groups, have invaded freshwater drainages of Central and South America. Each of the three species groups were found …


Phenotypic Clines In The Intertidal Snail Littorina Obtusata: The Role Of Water Temperature And Predator Effluent As Inducers Of Phenotypic Plasticity And Associated Trade-Offs In Shell Form, Geoffrey Clayton Trussell Jan 1998

Phenotypic Clines In The Intertidal Snail Littorina Obtusata: The Role Of Water Temperature And Predator Effluent As Inducers Of Phenotypic Plasticity And Associated Trade-Offs In Shell Form, Geoffrey Clayton Trussell

Dissertations, Theses, and Masters Projects

I examined variability in the shell form of 25 Littorina obtusata populations from Massachusetts to northern Maine. I chose this scale because the history of one of L. obtusata's principal predators, the crab Carcinus maenas, has changed dramatically in the past 100 years. Before 1900, Carcinus did not occur north of Cape Cod, Massachusetts, but by 1950 it had reached Canadian border. Moreover, in summer water temperatures during average 6-8&\sp\circ&C colder at northern locations. Shell thickness and mass increased and body mass decreased with increasing latitude. to test whether these patterns reflect plasticity in response to predators, snails from two …