The theory of punctuated equilibrium requires one form of this process to be less common than another; the latter form of this process was postulated by Ernst Mayr and is sometimes considered a subtype of the former. That form of this process occurs when a subgroup colonizes an area on the borders of the population's viable range, resulting in substantial genetic drift, and is called peripatric. The vicariant form of one type of this process occurs when a geologic event 
The theory of punctuated equilibrium requires one form of this process to be less common than another; the latter form of this process was postulated by Ernst Mayr and is sometimes considered a subtype of the former. That form of this process occurs when a subgroup colonizes an area on the borders of the population's viable range, resulting in substantial genetic drift, and is called peripatric. The vicariant form of one type of this process occurs when a geologic event separates an extant population into two roughly equal groups; that type is called allopatric. For 10 points, name this process wherein two populations begin to reproduce separately, eventually isolating and forming new examples of a taxonomic classification more specific than genus.
The theory of punctuated equilibrium requires one form of this process to be less common than another; the latter form of this process was postulated by Ernst Mayr and is sometimes considered a subtype of the former.
{speciation} [accept {allopatric} speciation before mentioned; prompt on {evolution}]