Bird Watching (UK) - - Your View -

En­demic is one of those con­fus­ing words, with two very dis­tinct mean­ings de­pend­ing on how it is be­ing used. Of­ten used on tele­vi­sion to mean “wide­spread” or “com­mon”, as in “cor­rup­tion is en­demic”, in the bird­ing world en­demic means some­thing quite dif­fer­ent. To a birder, or in­deed to any nat­u­ral­ist, en­demic refers to a species that is found in one lo­ca­tion and no other. As there is no ac­cepted up­per limit for the size of such a lo­ca­tion, we could say that all birds are en­demic to the Earth, but usu­ally the term is used in ref­er­ence to smaller ge­o­graph­i­cal ar­eas, such as deserts or coun­tries. There are two dis­tinct forms of en­demism; firstly we have what are called ‘neoen­demic’ birds, which are those that have evolved in one place and have never been found any­where else, such as the fa­mous Gala­pa­gos finches. Then there are ‘pa­le­oen­demic’ birds that were for­merly wide­spread and have for var­i­ous rea­sons dwin­dled un­til only one pop­u­la­tion re­mains, a sit­u­a­tion that un­for­tu­nately looks like be­com­ing more com­mon. The num­ber of en­demic species in an area does not seem to be re­lated to the size of that area ei­ther; whereas Sri Lanka has nearly 30 birds en­demic to the is­land, Bri­tain’s only en­demic bird is the Scot­tish Cross­bill, once thought to be a sub­species of Cross­bill, but granted species sta­tus in the late 20th Cen­tury.

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