Peripatric speciation

Definition
noun
A speciation in which new species evolve in a sub-population that colonized a new habitat or niche within the same geographical area of the ancestral species, and experience genetic drift.
Supplement
Similar to allopatric speciation, peripatric speciation involves populations being geographically separated and prevented from exchanging genes. It differs from the allopatric speciation in a way that the population separating from the main population involves a smaller unit.
An example of this is the London Underground mosquito, a variant of the mosquito Culex pipiens, which entered in the London Undgerground in 19th century. Evidence for its speciation includes genetic divergence, behavioural differences, and difficulty in mating.
Word origin: Greek, from peri, around, near + Greek patrā, fatherland.
Compare: allopatric speciation, parapatric speciation, sympatric speciation.

See also: speciation, genetic isolation.