BIOL 121 Lecture Notes - Lecture 19: Species Complex, Speciation, Allopatric Speciation
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Not applicable to asexual or fossil species; difficult to assess if populations don"t breed & don"t evolutionary produce viable independence do not overlap geographically. Subjective (research often disagree about how much or what kinds of morphological distinction indicate speciation); misses cryptic species. Widely applicable; based on testable on phylogenetic criteria currently available tree. Speciation that begins with physical isolation via either dispersal or vicariance. Genetic isolation happens routinely when populations become physically separated. E. g. if a new physical barrier like a mountain range/ river splits the geographic. Physical isolation via dispersal or vicariance produces genetic isolation range of a species. Sympatric speciation geographic area or at least close enough to 1 another to make interbreeding possible. Speciation that occurs even though gene flow is possible (rare or non-existent) Sympatric population are not physically isolated, but may be isolated by preferences for different habitats. Polyploidy speciation (polyploidy has more than 2 chromosome copies) Due to a major mutation/ genetic change.
