Credit: Paul Krawczuk/Flickr, CC BY
By Frank Nicholas
When Charles Darwin visited the Galapagos Islands in October 1835, he and his ship-mates on board HMS Beagle collected specimens of birds, including finches and mockingbirds, from various islands of the archipelago.
At the time, Darwin took little interest in the quaint finches, making only a one-word mention of them in his diary. As painstakingly shown by Frank Sulloway and more recently by John Van Whye, it wasn’t until two years later that the finches sparked Darwin’s interest.
By then he had received feedback from the leading taxonomist of the time, John Gould, that the samples comprised 14 distinct species, none of which had been previously described! Gould also noted that their “principal peculiarity consisted in the bill [i.e. beak] presenting several distinct modifications of form”.
So intrigued was Darwin by this variation in size and shape of beaks that in the second (1845) edition of Journal of Researches he included illustrations of the distinctive variation between species in the size and shape of their beaks. He added a comment that:
Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.
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