GALAPAGOS FINCHES SPECIATE according to reports in BBC News and ScienceDaily 24 November 2017, and Science doi: 10.1126/science.aao4593, 23 November 2017. A group of scientists from Sweden and USA claim to have observed a new species of finch evolve on the Galapagos Island of Daphne Major. In 1981 a male Large Cactus Finch Geospiza conirostris from the island of Espanola arrived on Daphne Major and mated with a female Medium Cactus Finch Geospiza fortis. One of the male offspring of this pair mated with another G. fortis female, but from then on the descendants of both of these pairs have only bred with each other, and not with any of the other finches on the island. The native G. fortis females tend not to be attracted to the hybrid males because the males sing a different song to the G. fortis males. In spite of the inbreeding the offspring have been fertile, and so far six generations have been produced since the original pairing. These birds have been nicknamed the Big Bird lineage, as they are larger in overall body size and beak size than the native Medium Cactus Finches. Because they do not breed with the other finches on the island they are considered to be reproductively isolated, and therefore can be considered a separate species. The researchers wrote in their report: “This example shows that reproductive isolation, which typically develops over hundreds of generations, can be established in only three”.
Links: BBC, ScienceDaily
ED. COM. The formation of the initial hybrid is no surprise as Galapagos finches with different species labels have been known for many years to hybridise and produce fertile offspring. This has further been confirmed by recent genetic studies that show extensive gene flow between separately named species. See our report Finch Gene Flow. This new study confirms previous studies in two areas: that (1) given opportunity, e.g. being on the same island, and (2) motivation, e.g. not enough available mates of the same species, the finches can interbreed successfully. These birds do show the formation of a group of individuals that breed amongst themselves, but not with outsiders, is a real event, but since the birds are still all finches, and show no signs of turning into another kind of bird, it is not evolution in any sense. In fact we need to note how far the goal posts have been shifted here – interbreeding of two separately named species that has produced fertile offspring has traditionally been regarded as evidence that two types were actually only one species. We can broaden this by stating that all studies of Galapagos finches, wherever they live and whatever they are named, confirm that they are all really members of one kind, and have split into subgroups by choice and necessity as they spread out amongst the different islands. As such these birds are not icons of evolution, but confirmation of Genesis, which tells us that God created the birds according to their kinds.
To illustrate the extreme folly of this goal-post shift ... would you argue that tall Zulus mating with small Pygmies to produce intermediate size humans who then choose to mate only with similar size humans is evolution? Talk about grasping at straws! Creation Research.
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