Bird embryos uncover homology and evolution of the dinosaur ankle


The early formation of the limb skeleton is often assumed to be well known from ‘classic’ published lines of work using traditional techniques and model species. However, it is worth revising this basic information. New methods and better taxon sampling can provide increased detail and substantial revision, with important evolutionary implications. In addition to the fossil record, reliable embryological data from birds are important to understand their evolution from dinosaurs17.

Reported as: The dinosaur ankle re-evolved amphibian-like development in birds

This work has revealed that the ascending process does not develop from either the heel bone or the ankle bone, but from a third element, the intermedium. In the ancient lineage of paleognath birds (such as tinamous, ostriches and kiwis) the intermedium comes closer to the anklebone, producing a dinosaur-like pattern. However, in the other major avian branch (neognaths), which includes most species of living birds, it comes closer to the heel bone; that creates the impression it is a different structure, when it is actually the same. “It puts the final nail in the anti-dinosaur coffin” says Jacques Gauthier, a vertebrate paleontologist and professor at Yale University “The dinosaurian ascending process is retained in all birds, though it has changed its association from ankle to heel bones in neognath birds.”

My comment: The report that an evolutionary process automagically changed as increasing nutrient energy-dependent pheromone-controlled morphological and behavioral phenotypes disappeared and reappeared gives much more credit to the magic of evolution than ever before.

For comparison see: This is an example of energy-dependent virucidal UV fluorescence. It was reported in the context of mutation-driven evolution and the weekend resurrection of the flagellum in Pseudomonas fluorescens. The claim that an irreducibly complex functional structure could be resurrected links the nutrient-dependent pheromone-controlled physiology of reproduction to all differences in morphological and behavioral phenotypes in all living genera. Pseudoscientists, atheists, and ever some researchers who claim to be young earth creationists seem to believe this example of energy-dependent autophagy is an example of autofluorescence.


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