BIOL 103 Lecture Notes - Ploidy, Gamete, Adaptive Radiation
Document Summary
How are species formed: gradually in situ or by more rapid division of ancestral population, usually allopatric, sometimes in sympatry. How do species persist: gene flow reduced by rima". Variation within and between groups of organisms is common. Morphospecies were the traditional way of describing species, going back to the latin naming system created by swedish biologist carl linnaeus in the mid 1700s: works where clear groups are defined by reliable characters. Monkeyflow" species of the genus mimulus share distinct floral morphology and other traits associated with their preferred pollinators and habitats. Different species concepts each have strengths and weaknesses more than one may be useful depending on context and question. Few phylogenies phylogenetic group testable available independence and fossils. Speciation: population becomes reproductively isolated, separated gene pools diverge, due to genetic drift and local adaptation, genetic exchange stops, new lineages go their independent evolutionary ways.