BIO120H1 Lecture Notes - Lecture 9: Sympatric Speciation, Ecological Speciation, Allopatric Speciation

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12 Jul 2017
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BIO120H1 Full Course Notes
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BIO120H1 Full Course Notes
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36 documents

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Hypothesis: no selection against mutations that impair flight. Important as antipredator mechanism, but not many predators on islands. May be disadvantageous (could fly out to sea and never come back) Not flying can be an advantage when there are no predators. Can be impediment when going down deep into water. Allows them to dive in a much more physically efficient manner. Hawaiian honeycreepers have all descended from a single species of finch in the last 10 million years. Darwin: i look at the term species, as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other (morphological characterization of species) Coyne: when we understand the origin of reproductive isolating factors, we understand the origin of species (to understand species, have to understand how reproductive isolation occurs) Two main species concepts: taxonomic/morphological: based primarily on distinct morphological differences, biological: based on inter-fertility (crossability) among individuals.