Difference Between Allopatric Speciation vs. Sympatric Speciation

Main Difference

Speciation is defined as the formation of distinct and new species in the process of evolution. It is divided into many modes, and we will discuss allopatric speciation and sympatric speciation here. Allopatric speciation is the mode of speciation that takes place when biological populations of the similar species become vicariant. In this speciation, there is interferes with genetic interchange. And, the sympatric speciation is the mode of speciation through which we evolve new species from a single ancestral species. In this speciation, two or more populations of a species are involved.

Comparison Chart

Allopatric SpeciationSympatric Speciation
DefinitionAllopatric speciation is the mode of speciation that takes place when biological populations of the similar species become vicarian.Sympatric speciation is the mode of speciation through which we evolve new species from a single ancestral
OccurrenceIn allopatric speciation, genetic modification occur in the populations that are distributed.Sympatric speciation has a genetic modification in the common ancestor.
VariationIn allopatric speciation, the change is due to the difference in the environmental factors.In sympatric speciation, change is in the individuals that are selected naturally.
PopulationAllopatric speciation involves one population in it.Sympatric speciation involves two or more populations.

What is Allopatric Speciation?

Allopatric speciation is also named as geographical speciation. Allopatric speciation is the mode of speciation that takes place when biological populations of the similar species become vicariant. In this speciation, there is interferes with genetic interchange. It is said as geographical because one species become two just due to the formation of some geographical barriers, these barriers are like land separation, migration or mountain formation. When such barriers are formed between species, there occur an isolation of one portion of a particular population. Then due to factors like ecological conditions and environmental changes, these species are modified and adapted according to it, and modifications take place which produces differences in these species. There may be mutation and changes in the genetics according to the demand of the environment etc. These adaptations are necessary for the survival of the species, if no adaptation occur, the species may die in the change that occurs In its surroundings. Adaptations are according to the demand of the environment in which that species live. In the result, finally, the species are isolated from one another.

What is Sympatric Speciation?

Sympatric speciation is also one of the modes of speciation. Sympatric speciation is the mode of speciation through which we evolve new species from a single ancestral species. In this speciation, two or more populations of a species are involved. In the sympatric speciation, there is a single ancestor of all species. New species are formed because of genetic modifications in the ancestor. There is no geographical range in this mode; all the species have the same range of geographical area. The difference in the populations occurs because of the individuals who are selected by nature. The mating preferences form new groups and subgroups. Many theories were proposed for this mode, but the most acceptable theory was “Disruptive Selection Model” that was proposed by John Maynard Smith in 1966. According to this, homologous individuals are more favored than heterozygous individuals. This cause a species to be diverted into two subgroups that have survived having the homozygous dominant genotype and other with homozygous recessive. These homozygous groups will form two separate species with the passage of time.

Allopatric Speciation vs. Sympatric Speciation

  • Allopatric speciation is the mode of speciation that takes place when biological populations of the similar species become vicariant, whereas sympatric speciation is the mode of speciation through which we evolve new species from a single ancestral.
  • Allopatric speciation has geographical barriers between species whereas sympatric speciation has a same geographical area between them.
  • In allopatric speciation, genetic modification occur in the populations that are distributed whereas, sympatric speciation has a genetic modification in the common ancestor.
  • In allopatric speciation, the change is due to the difference in the environmental factors, on the other hand, in sympatric speciation, change is in the individuals that are selected naturally.
  • Allopatric speciation involves one population in it whereas, sympatric speciation involve two or more populations.

Comparison Video

Author: