Describes why similar organisms do not interbreed because of a physical barrier.

asexual reproduction

sympatric speciation

the biological species concept

allopatric speciation

Allopatric Speciation describes why similar organisms do not interbreed because of a physical barrier.

Explanation:

The specific situation in which the population of identical species doesn’t interbreed or leaves in isolation with each other is referred as ‘allopatric speciation’.  It is also considered a specification of geographical factors.

The factors that work as a barrier to the process of breeding between same groups of organisms are- mountain formation, formation of water bodies, agriculture etc. These natural and human occurrences affect the geography of a place that influences the separation in species.

1.the evidene of the reaction

2.yes

3.yes

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).