Anchiornis: Foot Feathers Confuse Bird Evolution Story
The paper on Anchiornis huxleyii was published in Nature,1 along with a News article about it in the same issue by Lawrence Witmer.2 In addition, popular reports were printed by the BBC News, Live Science and Science Daily.
The popular reports are focusing on Xing Xu’s claim that this fossil removes the last argument that birds could not have evolved from dinosaurs because this fossil gets rid of the “temporal paradox” – the fact that the alleged “feathered dinosaurs” were all younger in the fossil record than Archaeopteryx, the earliest known bird. Anchiornis has been assigned to strata dated 1 to 10 million years earlier than Archaeopteryx, effectively removing that objection.
Other than that, this fossil is confusing. It has long feathers on all four legs – even on the hind feet. The feathers get shorter closer to the body. Scientists can’t figure out if the feathers allowed the creature to fly or glide. If not, what function did they perform? The animal had elongated hind legs. It seems that foot feathers would have interfered with flying and with walking on the ground. Some modern birds have feathered feet but not long, pennaceous feathers. Based on this new discovery, and on the previous fossils Microraptor gui (11/16/2005, 03/27/2007), and Pedopenna (feather-foot; see New Scientist 19 Feb 2005), evolutionary biologists are trying to piece together a story of feathers first evolving on the extremities and then moving inward toward the body. That begs the question of what the feathers evolved for in the first place. The authors try to explain,
Extensive feathering of the pes [foot] is also seen in some modern birds, and serves an insulating or protective function. In most cases the feathers are not organized into a coherent planar surface as in Microraptor, Pedopenna and Anchiornis, which indicates that the pedal feathers of these fossil taxa may have differed from those of extant birds in having an aerodynamic function. This would imply that a four-winged condition played a role in the origin of avian flight, as suggested by previous studies, although this conclusion is not universally accepted. However, the significant differences noted above between the large pedal feathers of Anchiornis and those of Microraptor suggest that these feathers might have been less aerodynamically effective in Anchiornis than in Microraptor.
It would seem that going from four wings to two wings represents devolution, not evolution, unless two wings are shown to be more efficient for flying. Even so, the sudden emergence of a four-winged animal would seem improbable for natural selection. Anchiornis adds to the puzzle by causing doubt that the feathers were aerodynamically effective. Yet distal feathers don’t seem to provide much of an insulating or protective function. Why would natural selection produce structures as complex as feathers for no purpose? Witmer explained,
More to the point, it now looks as if we’ll have to accept that avian evolution indeed went through – at the risk of overstatement – a four-wing stage, only to eventually lose the long foot feathers. What this means for the evolution of the avian flight stroke is now an open question. Likewise, we’ll need to seriously consider how these otherwise seemingly very adept and agile runners (Anchiornis has extremely long and slender hindlimbs) could manage with long feathers on their feet.
What does Anchiornis mean for evolutionary history? “The presence of a troodontid in the earliest Late Jurassic indicates that all groups of derived theropods had originated by this time,” the paper said. The common ancestor of these groups (Troodontidae, Dromaeosauridae and Avialae) therefore remains to be discovered earlier in the fossil record. Witmer took it as a plug for evolutionary theory that similarities in early representatives of these groups (e.g., the foot feathers) shows that paleontologists are converging on the common ancestor. “It’s getting hard to tell members of one group from another,” he said. “On the bright side, in this year of Darwin, that fact provides a comforting affirmation of the evolutionary prediction that species in different groups will become increasingly similar as we approach their common origin.”
1. Hu, Hou, Zhang and Xu, “A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus,” Nature 461, 640-643 (1 October 2009) | doi:10.1038/nature08322.
2. Lawrence M. Witmer, “Palaeontology: Feathered dinosaurs in a tangle,” Nature 461, 601-602 (1 October 2009) | doi:10.1038/461601a; Published online 30 September 2009.
This is an opportunity to compare hype with fact. The news media and the discoverers are all chirping that they have an example of bird evolution here. A transitional form between dinosaurs and birds has been found, and now the naysayers need to bow at the feet of the Charlie idol and admit they were wrong. It should be noticed that the Darwinists did not predict finding a dino-chicken with long feathers on its feet. What is this thing? Look at the predictions they had made. The ancestor of birds either learned to fly from the ground up (cursorial) or the tree down (arboreal). The cursorial hypothesis appears down and out if this animal had anything to do with it. Witmer just wondered how this animal could manage to run with feathers on its feet. Put some long feathers on your feet and see if it helps your takeoff. The arboreal hypothesis might still be a contender, but it is 09/06/2007 for the convoluted tale).
There remains no clear picture of the evolution of flight – particularly of powered flight and all the systems required to support it. There are only an assortment of odd, extinct creatures that paleontologists try to sort into man-made categories. Remember that it’s not just the taxonomic categories that assume evolution; it’s the geological categories and the dating methods. Evolutionary paleontology has become a self-fulfilling prophecy. Since the outcome is never in doubt, every find becomes part of the ever more complex story of evolution. They insulate their story from falsification by contorting any and all data to fit the story somehow. It is not science.
All right then, what are creationists saying? Creationists do not accept the dating scheme, the millions of years, the creative power of natural selection, or the phylogenetic stories. The strata diagram in the paper shows alternating bands of andesite, shale, siltstone, agglomerate and tuff. To accept the column, one has to believe that only one kind of material was deposited for many tens or thousands of years (longer than all human history), then another kind for more thousands of years, then another, then a repeat of the first type of material, over and over. Alternative mechanisms could allow for these layers to be deposited rapidly. The time interval between Anchiornis and Archaeopteryx and the other creatures could therefore be so small as to make them contemporaneous. These are questions evolutionists never ask because they are married to the Geologic Column. The whole Darwin story would collapse if it were called into question. Evolutionists need to get off the Lyellian bandwagon and recognize the paradigm-shaking powers of catastrophism. It could rewrite the history of the Liaoning deposits.
Anchiornis, then, represents another species that went extinct among a majority of past species that went extinct. It was not evolving into something better. If anything, it was evolving downward. Combine this with what we know about the Cambrian Explosion, the young material in dinosaur soft tissue, and the capacities for rapid geological change in catastrophes, and it is the Darwinists who need to explain themselves, not their critics. Hint: every time you find a Darwinist begging the question in his or her story, stop them right there. Say, “Excuse me, I do not accept that assumption. What do you mean there were ten million years between those two strata? Prove it. Were you there? I do not accept your line that this was a transitional form on the way to birds. Don’t you realize that taxonomists classified the maniraptorans and troodontids based on evolutionary assumptions that dinosaurs and birds are related by common ancestry? I do not accept those assumptions, therefore I do not accept the classification scheme and the story built on it.” Make them explain their story from first principles using observations and testable data. Then ask the hard questions: “Do you realize how many beneficial mutations would be required to make a feather out of a scale or piece of fuzz? How can you possibly believe it happened? Don’t you know that birds have exquisitely designed bones and wings and respiratory systems for powered flight? Have you seen a hummingbird or eagle? You expect me to believe that some dinosaur fell out of tree and gave rise to the cormorant and falcon? How is that even remotely imaginable, given the complexity of DNA codes and proteins and biochemical systems? A few oddball species interpreted within your scheme are not convincing. There should be thousands upon thousands of transitions showing every step along the way if your story were true. Why don’t you admit with anti-creationist Stephen Jay Gould that the presence of systematic gaps in the fossil record is the trade secret of paleontology? Come back when you can trade in facts, not dredge up isolated oddballs to force-fit into an increasingly implausible tale.”