3 resultados para Divergence dates

em Brock University, Canada


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Seven crayfish species from three genera of the subfamily Cambarinae were electrophoretically examined for genetic variation at a total of twenty-six loci. Polymorphism was detected primarily at three loci: Ao-2, Lap, and Pgi. The average heterozygosities over-all loci for each species were found to be very low when compared to most other invertebrate species that have been examined electrophoretically. With the exception of Cambarus bartoni, the interpopulation genetic identities are high within any given species. The average interspecific identities are somewhat lower and the average intergeneric identities are lower still. Populations, species and genera conform to the expected taxonomic progression. The two samples of ~ bartoni show high genetic similarity at only 50 percent of the loci compared. Locus by locus identity comparisons among species yield U-shaped distributions of genetic identities. Construction of a phylogenetic dendrogram using species mean genetic distances values shows that species grouping is in agreement with morphological taxonomy with the exception of the high similarity between Orconectespropinquus and Procambarus pictus. This high similarity suggests the possibility of a regulatory change between the two species. It appears that the low heterozygosities, high interpopulation genetic identities, and taxonomic mispositioning can all be explained on the basis of low mutation rates.

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One page from the 1984 daily planner of Donald Ziraldo, October 18, 1984, the page is filled with point form notes regarding GATT (General Agreement on Tariffs and Trade). One note reads "don't understand how serious". The second date from the planner is October 27th and the notes appear to be expressions/thoughts like "society wants self-gov't" and "Realities = Crossroads in the Labrynth"

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List of officers and dates of commissions and appointments in the 4th Regiment of the Lincoln Militia including the troop of cavalry in the 4th Lincoln Militia (2 pages, handwritten), June 18, 1838.