A paraspecies (a paraphyletic species) is a species, living or fossil, that gave rise to one or more daughter species without itself becoming extinct. The concept of a paraspecies emerges naturally from the Evolutionary Species Concept. Geographically widespread species that have given rise to one or more daughter species as peripheral isolates without themselves becoming extinct (i.e. through peripatric speciation) are examples of paraspecies. A well-known example is the evolution of modern humans Homo sapiens from the ancestral species Homo rhodesiensis.
Paraspecies are expected from evolutionary theory (Crisp and Chandler, 1996), and are empirical realities in many terrestrial and aquatic taxa (e.g. Patton and Smith, 1989; Bell and Foster, 1994.; Crisp and Chandler, 1996; Funk and Omland, 2003.; Albert et al., 2004; Turner et al., 2004; Hoskin, 2007; Feinstein, 2008; Lozier et al., 2008).
The evolution of the polar bear from the brown bear is a well-documented example of a living species that gave rise to another living species. Another examples of a living paraspecies is the North Island tuatara Sphenodon punctatus, which gave rise to the Brothers Island tuatara Sphenodon guntheri.
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