Variation

Variation - alleles Harmonia axyridis o Patterns thought to...

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Gene 3000 03-01-07 Development of Evolutionary Biology (Dr. Anderson’s first lecture) Slide 15 Orthogenesis – straight line/direction/pathway (ex. Increase in size) Mutationism – evolution by big mutational steps Saltationism – evolution by jumps Neo-Lamarckism – inheritance of acquired characteristics Variation of Organisms and Its Genetic Basis Rare Variants: Elaphe guttata o Color acts as camouflage – presence of all colors is wild-type Black, orange, and albino mutants caused by recessive mutations Collinsia grandiflora o Albino mutants lack pigment and are susceptible to disease Mytilus edulis o Blue and brown (brown is dominant); there are no adaptive differences Clarkia amoena o Spotted from is dominant, both are found frequently in nature Pisaster ochraceus o Purple and orange, continuous variation may be present due to many
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Unformatted text preview: alleles Harmonia axyridis o Patterns thought to be determined by multiple alleles of a single gene; pattern is correlated with geography Foxglove o Colors are due to 3 genes, speckling is also present All other examples of variation are in the notes online Beak of the Finch Discussion (ch. 1-3) Why does the Origin of Species focus on pigeons, not finches? Pigeons were available for Darwin to study, he knew pigeon breeders and he became one; Darwin thought that people would be more able to relate to pigeons than to finches Why are the Galapagos Islands good to study? They are isolated There are enough species and individuals to study, but not too many The climate and geography is similar from island to island Infinite variation (beaks) 1...
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