Intraspecific lineages as focal points in the extinction and persistence of species
A deteriorating environment causes species’ range contraction and places species on a trajectory toward rarity and ultimately extinction. Contraction hypotheses focus on the cumulative demise of single populations or groups thereof, without regard to their evolutionary/genetic affinity. I propose that genealogical lineages, be they referred to as subspecies, ecogeographical races, or otherwise, are focal points in the extinction trajectory of species. Such intraspecific entities are likely to be well integrated and respond individualistically to environmental change. Given that these entities have disparate geographical footprints, substantive and varied environmental degradation across a species’ range may cause the demise of intraspecific entities independently of each other. Eventually, all lineages may go extinct and with that the species as a whole. Biodiversity loss has tended to be measured in terms of changes in population and species numbers. The development and implementation of improved conservation policies is contingent upon recognizing the importance of discrete lineages in species survival.
KeywordsEnvironmental change Extinction Intraspecific lineages/taxa Persistence
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Conflict of interest
There are no conflicts of interest or plagiarism.
Human and animal rights
No humans or animals were involved in the study, which is based only on the literature.
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