Fossil Friday: A Waiting Time Problem for Feathers
This Fossil Friday features a beautiful fossil feather from the Lower Cretaceous Crato limestones of northeast Brazil, which are about 115 million years old. I photographed this fossil at a German trader collection in July 2008. The feather with preserved color pattern could have belonged to a primitive bird or a feathered theropod dinosaur, which coexisted at this time in Earth history. Actually, the origin of pennaceous feathers represents another striking example of the waiting time problem as an obstacle to neo-Darwinian evolution. The rich fossil record of the dinosaur-bird transition shows that there are only a few million years available for the transformation of hair-like dino-fuzz into real bird feathers. This window of time corresponds to only about the average longevity of a single species, but has to accommodate the origin and fixation of multiple coordinated mutations to allow for the formation of vaned feathers, which are considered the most complex integumental structures in the animal kingdom.
Mathematical calculations based on mainstream population genetics strongly suggest that this time interval is much too short for such a transition to be plausibly explained with a blind process of natural selection acting on random mutations. Birds may well have descended from small bipedal dinosaurs, but this transition arguably required the input of very specific new genetic information that had to come from somewhere. Wherever you look in the history of life you stumble upon overwhelming evidence for design.
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