[Answer] The different finch species found on the Galápagos Islands probably arose as a result of _____.

Answer: Adaptive radiation
The different finch species found on the Galápagos Islands probably arose as a result of _____.
Darwin’s finches (also known as the Galápagos finches) are a group of about 18 species of passerine birds. They are well known for their remarkable diversity in beak form and function. They are often classified as the subfamily Geospizinae or tribe Geospizini. They belong to the tanager family and are not closely related to the true finches. The closest known relative of the Galápagos finches is the S…
Darwin’s finches (also known as the Galápagos finches) are a group of about 18 species of passerine birds. They are well known for their remarkable diversity in beak form and function. They are often classified as the subfamily Geospizinae or tribe Geospizini. They belong to the tanager family and are not closely related to the true finches. The closest known relative of the Galápagos finches is the South American Tiaris obscurus. They were first collected by Charles Darwin on the Galápagos Islands during the second voyage of the Beagle. Apart from the Cocos finch which is from Cocos Island the others are found only on the Galápagos Islands. The term “Darwin’s finches” was first applied by Percy Lowe in 1936 and popularised in 1947 by David Lack in his book Darwin’s Finches. Lack based his analysis on the large collection of museum specimens collected by the 1905–06 Galápagos expedition of the California Academy of Sciences to whom Lack dedicated his 1947 book. The birds vary in size from 10 to 20 cm and weigh between 8 and 38 grams. The smallest are the warbler-finches and the largest is the vegetarian finch. The most important differences between species are in the size and shape of their beaks which are highly adapted to different food sources. The birds are all dull-coloured.
During the survey voyage of HMS Beagle Darwin was unaware of the significance of the birds of the Galápagos. He had learned how to preserve bird specimens from John Edmonstone while at the University of Edinburgh and had been keen on shooting but he had no expertise in ornithology and by this stage of the voyage concentrated mainly on geology. In Galápagos he mostly left bird sho…
During the survey voyage of HMS Beagle Darwin was unaware of the significance of the birds of the Galápagos. He had learned how to preserve bird specimens from John Edmonstone while at the University of Edinburgh and had been keen on shooting but he had no expertise in ornithology and by this stage of the voyage concentrated mainly on geology. In Galápagos he mostly left bird shooting to his servant Syms Covington . Nonetheless these birds were to play an important part in the inception of Darwin’s theory of evolution by natural selection . On the Galápagos Islands and afterward Darwin thought in terms of “centres of creation” and rejected ideas concerning the transmutation of species . From Henslow s teaching he was interested in the geographical distribution of species particularly links between species on oceanic islands and on nearby continents. On Chatham Island he recorded that a mockingbird was similar to those he had seen in Chile and after finding a different one on Charles Island he carefully noted where mockingbirds had been caught. In contrast he paid little attention to the finches. When examining his specimens on the way to Tahiti Darwin noted that all of the mockingbirds on Charles Island were of one species those from Albemarle of another and those from James and Chatham Islands of a third. As they sailed home about nine months later this together with other facts including what he had heard about Galápagos tortoises made him wonder about the stability of species. Following his return from the voyage Darwin presented the finches to the Zoological Society of London on 4 January 1837 along with other mammal and bird specimens that he had collected. …

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