What is the Difference Between Parapatric and Sympatric Speciation?

Parapatric and sympatric speciation are two modes of speciation, which is the process by which new species are formed. The main difference between these two modes lies in the geographical distribution of the populations and the degree of gene flow between them:

• Parapatric speciation: This mode occurs when new species are formed from a continuously distributed population, meaning that the populations are spread out over a large geographic area but not geographically isolated from one another. In parapatric speciation, the populations occupy distinct niches in their environment and are separated by ecological factors. Gene flow between the populations is not completely restricted, but it is reduced, allowing genetic differences to accumulate over time and eventually lead to the formation of new species.
• Sympatric speciation: This mode occurs when new species are formed from within the range of the ancestral population, meaning that the populations share the same ecological niche. In sympatric speciation, the frequency of gene flow between the populations is high, and reproductive isolation is not initially present. However, genetic differences can still accumulate due to factors such as natural selection or genetic drift, eventually leading to the formation of new species.

In summary, the main difference between parapatric and sympatric speciation is the degree of geographical separation between the populations and the extent of gene flow between them. Parapatric speciation involves populations that are spread out but not geographically isolated, while sympatric speciation involves populations that share the same ecological niche and have high gene flow. Both modes can lead to the formation of new species, but the processes involved differ in terms of geographical context and levels of gene flow.

Comparative Table: Parapatric vs Sympatric Speciation

Here is a table comparing parapatric and sympatric speciation: