DNA Studies Show Microevolution In Penguins

DNA Studies Show Microevolution In Penguins: "Comparison across thousands of years is possible because the extremely cold and dry conditions of the southernmost continent--conditions found almost nowhere else on Earth--preserved the ancient penguins' physical remains so well. The new study shows that the alleles -- slight variations in the coding of genes -- from ancient birds differ in several significant ways from those in modern populations in the same area. The researchers found that the DNA sequences for some of the genes had become longer over time, and that the frequency of some of the different genes had changed as well."