Finch beak variation described in Nature, vol. 442, p563, 3 Aug 2006. Changes in beak shape of Galapagos Island finches are presented in textbooks and popular media as a classic example of evolution of new species. A group of researchers led by Arhat Abzhanov of the Harvard Medical School, Massachusetts, have studied the development of finch beaks as the birds develop inside the eggs. They found that variations in the amount of a molecule named calmodulin (CaM) regulates the length of the beak. Increased levels of CaM result in increased length of the beak, resulting in a beak like that of the cactus finch. Several years ago variations in another molecule named Bmp4 was found to regulate the depth and thickness of the beak. The Harvard researchers suggest that combinations of levels of these two molecules can explain all variations in beak shape and size between the different finch species, e.g. high CaM and low Bmp4 results in the long thin beak like a cactus finch, low CaM and high Bmp4 gives a short stout beak of the large ground finch.
Editorial Comment: This is exactly what you would predict if the birds were variations within one created Finch Kind. Apart from their beaks and their feeding behaviour, the Galapagos finches are remarkably similar, and hybrids between them can produce fertile offspring. The study described above confirms that the variation in beak shape is just built in variability in the same gene that ensures that some Finches within the population can survive if the environment changes. The more research that is done on the finches the more the evidence fits with the Genesis account of living creatures being made as separate Kinds. (Ref. adaptation, development, kinds)
Evidence News 9 August 2006