BIO152H5 Chapter Notes - Chapter 24: Ecological Niche, Allele Frequency, Gene Flow
Document Summary
Barriers impeding two species from producing viable, fertile offspring (before or after fertilization) Before fertilization (prezygotic): impede members of diff species from attempting to mate, prevent the succesfful completion of a mating, or hindering fertilization if mating is completed: habitat isolation. Species cannot interact due to differences in habitats: temporal isolation, behavioural isolation. Organisms breed at different times, different seasons. Courtship displays that attract a mate are different: mechanical isolation. Organs do not work, or do not fit: gametic isolation. Defects in sperm or eggs, that cannot make offspring. Speciation: the process by which one species splits into two or more species. Responsible for unity in diversity (similarities within differences of species) Yields new species that differ from existing ones. Forms a bridge between microevolution: changes in allele frequencies in a pop"t over time and macroevolution: the broad pattern of evolution.
