Finch gene flow reported in BBC News, Nature news and ScienceDaily 11 February 2015. A group of scientists from Princeton and Uppsala Universities have carried out an extensive study of the genomes of finches of the Galapagos Islands, otherwise known as “Darwin’s Finches”. The researchers compared genomes of 120 birds, including individuals from all finch species on the Galapagos Island, along with birds from the Cocos Island and the South American mainland.
They found there was “extensive evidence for interspecific gene flow, i.e. movement of genes between different species. This fits with previous observations that finches classified as different species do breed with one another, and the resulting offspring are fertile, and not sterile as true hybrids are. The resulting finch offspring can mate with an individual from either of the two parental species, and also produce fertile offspring.
The most distinctive difference between the offspring and parent birds is the size and shape of their beaks. Over the last decade scientists have found a number of genes that contribute to beak size and shape. This new study examined a gene named ALX1. The research team found two variations of this gene. One variant was associated with pointed beaks, and was found in all cactus finches, which feed on cactus flowers. The other was associated with blunt beaks, and was found in seed eating birds such as the large ground finch. Medium ground finches, which have some variation in beak shape within the one species, have a mix of the two variants.
Editorial Comment: Although these birds are often referred to as “Darwin’s Finches” Darwin wrote very little about them, and he did not use them as evidence for his theory in Origin of Species. Darwin simply collected some specimens, made a passing reference to them is his journal, and delivered them to the British Museum. Others then classified them into different species and turned them into icons of evolution.
However, this study confirms they are really variations of the same finch kind as we have always stated, and the extensive gene flow between species is no surprise to us. This new study of finch genes is further confirmation that beak shapes are not proof of evolution, even though they are used in biology textbooks as a classic case of evolution over millions of years. Interbreeding of ‘different beak shaped’ birds produces new beak shapes in one generation, not millions of years, and has nothing to do with environmental induced evolution at all. The fact that the variety of beak shapes is simply the result of mixing variations of the same genes reinforces the evidence they are all of one kind.
The different beak shapes do allow the birds to exploit different food sources, but this is not evolution. Narrow pointed beaks are suitable for inserting into cactus flowers, but not much use for cracking seeds. Thick blunt beaks are good for cracking seeds. Therefore, birds will survive wherever there is appropriate food for their beak shape, and die out where the right food is not available. This is natural selection, but it is not evolution.
These results are confirmation of what creationists have been saying for many years, i.e. the Galapagos finches are all one finch kind, and the beak shapes are simply variation within kind. (Ref. genetics, hybrids, ornithology)
Evidence News vol. 15, No. 2
25 February 2015
Creation Research Australia