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Sunday 17 September 2017

Occam's razor to too dull for Darwinism?

With Two New Fossils, Evolutionists Rewrite Narratives to Accommodate Conflicting Evidence
Günter Bechly 


Two new fossils, described in August and September 2017, have again forced evolutionists to rewrite their fanciful narratives of how major transitions in the history of life occurred. In this case the new fossils disarrayed, respectively, the origin of tetrapod land vertebrates and of bird feathers and flight.

The first fossil, described by Lefèvre et al. (2017), is a feathered dinosaur named Serikornis sungei (nicknamed “Silky”), which lived about 160 million years ago during the Upper Jurassic era. Found in China’s Liaoning province, it is a beautifully preserved complete animal with visible dino-fuzz covering its body. It was about the size of a pheasant and its morphology suggests that it was unable to fly and “spent its life scampering around on the forest floor” (Pickrell 2017). The most striking feature is the fact that even though its arms and legs have long feathers, so that the fossil seems to qualify as a member of the four-winged group of “dino-birds” such as Microraptor, Anchiornis, and Xiaotingia, the arms are much too short for wings. The feathers also lack the second order branchings (barbules) of true pennaceous flight feathers.

There are two interesting issues with this remarkable feathered dinosaur (and no, it does not seem to be a forgery like the “missing link” Archaeoraptor, Rowe et al. 2001):

The distribution and type of feathers on its body are not consistent with the currently preferred scenario about the evolution of bird feathers and flight. That scenario assumes that long pennaceous feathers on arms and legs originated with arboreal four-winged gliders such as Microraptor (Pickrell 2017)
The new phylogenetic tree in the original publication by Lefèvre et al. again reshuffles the feathered dinosaurs and early birds into a new branching pattern, disagreeing with previous trees that, in turn, all disagree with each other. Constructing phylogenetic trees looks more and more like an arbitrary enterprise, evolutionary biology’s equivalent of other pseudoscientific methods such as psychoanalysis or the Rorschach test.
The second fossil discovery, by  Zhu et al. (2017), is a new species of lobe-finned fish named Hongyu chowi from the Late Devonian. Discovered at the Shixiagou quarry in northern China, it was about 1.5 metres long, and lived 370 to 360 million years ago. One of its describers happens to be the famous Swedish paleontologist Per Ahlberg from Uppsala University, who also made worldwide headlines this month (e.g.,Ancient footprints in Greece trample on the theory of human evolution,” in The Times of London) with the description of 5.7-million-year-old human footprints from Crete (see Bechly 2017).

Barras (2017) announces at New Scientist that this “Weird fish fossil changes the story of how we moved onto land.” From the article:


[W]hen the researchers tried to fit H. chowi into the existing evolutionary tree, it didn’t fit easily.

That’s because in some respects, H. chowi looks like an ancient predatory fish called rhizodonts. These are thought to have branched off from lobe-finned fish long before the group gave rise to four-legged land animals.

But Ahlberg says H. chowi has aspects that look surprisingly like those seen in early four-legged animals and their nearest fishy relatives —an extinct group called the elpistostegids. These include the shoulder girdle and the support region for its gill covers.

This implies one of two things, the researchers say. The first possibility is that H. chowi is some sort of rhizodont that independently evolved the shoulders and gill cover supports of a four-legged animal.

Alternatively, the rhizodonts may be more closely related to the four-legged animals and the elpistostegids than we thought. But this would also imply a certain amount of independent evolution of similar features, because the rhizodonts would then sit between two groups that have many features in common – features the two groups would have had to evolve independently. …

The find confirms an earlier suspicion that there was independent or “parallel” evolution between the rhizodonts, the elpistostegids and the first four-legged animals, says Neil Shubin at the University of Chicago.

Thus, this fossil raises two important problems for evolutionary biology:

The character distribution is incongruent and implies independent parallel origins of the same tetrapod-like or rhizodont-like characters (convergence). The alternative explanations of independent origin (homoplasy) versus common origin (homology) of a character trait is not alone decided based on anatomic (dis)similarities but mainly based on the (in)congruence with other data. The same data that are considered evidence of convergence can become evidence for common ancestry when you switch positions in the tree, and vice versa. What most evolutionary biologists have exorcised from their mind is that such incongruences (homoplasies) per se are not evidence for evolution as some evolutionists boldly proclaim (Wells 2017) but, instead, prima facie conflicting evidence against it (Hunter 2017). Convergence, which Lee Spetner has called “even more implausible than evolution itself” (Klinghoffer 2017), and other incongruent similarities have to be explained away with ad hoc hypotheses. In past decades, convergence morphed from an inconvenient exception to the rule — to a ubiquitous phenomenon, found virtually everywhere in living nature. In his book Life’s Solution, paleontologist Conway Morris (2003) felt compelled to declare it a kind of necessary natural law. It thus cannot really be considered a success story for the Darwinian paradigm.
Rhizodontids,the group to which this fossil fish belongs, are believed to have branched off early from the lobefin-tetrapod lineage, more than 415 million years ago. However, the oldest fossils are dated to only 377 million years ago, implying a so-called “ghost lineage” of 38 million years when the group should have existed but left no fossil record at all. Such “ghost lineages” are one of the many instances of discontinuity in the fossil record and require ad hoc assumptions in order to be accommodated by evolutionary storytelling.
These two new fossils represent further evidence conflicting with previously accepted evolutionary narratives. But thank God evolutionary theory can easily adapt to such inconvenient evidence, simply by rewriting the story. That way, the new evidence fits perfectly.

Dubious procedures like these would be unthinkable in other natural sciences, such as physics. They call into question whether evolutionary biology really qualifies as a hard science at all. Arguably it is not a testable theory, or even a well-defined one, but merely a loose collection of narratives that are forged to fit the evidence — any evidence whatsoever.

Literature:

Barras C 2017. Weird fish fossil changes the story of how we moved onto land.  New Scientist 4 September 2017.
Bechly G 2017. Fossil Footprints from Crete Deepen Controversy on Human Origins. Evolution News September 6, 2017.
Carassava A 2017. Ancient footprints in Greece trample on the theory of human evolution.  The TimesSeptember 4 2017.
Hunter C 2017. The Real Problem With Convergence. Evolution News May 25, 2017.
Klinghoffer D 2017. “Convergent Evolution Is Even More Improbable than Evolution Itself.”  Evolution News September 5, 2017.
Lefèvre U, Cau A, Cincotta A, Hu D, Chinsamy A, Escuillié F, Godefroit P 2017. A new Jurassic theropod from China documents a transitional step in the macrostructure of feathers.  The Science of Nature 104:74.
Conway Morris S 2003. Life’s Solution: Inevitable Humans in a Lonely Universe. Cambridge University Press.
Pickrell J 2017. New Feathered Dinosaur Had Four Wings but Couldn’t Fly.  National Geographic August 28, 2017.
Rowe T et al. 2001. Forensic palaeontology: The Archaeoraptor forgery. Nature 410: 539-540.
Wells J 2017. Zombie Science: Jonathan Wells on Convergence Versus Common Ancestry.  Evolution News June 28, 2017.

Zhu M, Ahlberg PE, Zhao W-J, Jia L-T 2017. A Devonian tetrapod-like fish reveals substantial parallelism in stem tetrapod evolution. Nature Ecology & Evolution.

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