July 2, 2010 | David F. Coppedge

Humans Got Birdbrains by Convergent Evolution

Scientists are learning that birds have brains remarkably similar to those of mammals.  This is contrary to a century of belief, PhysOrg said.  How did such similarities evolve for groups of animals so widely separated?  To explain it, evolutionists pulled out one of their common explanations: convergent evolution.
    “For more than a century,” the article began, “neuroscientists believed that the brains of humans and other mammals differed from the brains of other animals, such as birds (and so were presumably better).”  Now, scientists at UC San Diego School of Medicine are finding that “a comparable region in the brains of chickens concerned with analyzing auditory inputs is constructed similarly to that of mammals.”  Specifically, “They discovered that the avian cortical region was also composed of laminated layers of cells linked by narrow, radial columns of different types of cells with extensive interconnections that form microcircuits that are virtually identical to those found in the mammalian cortex.”  This “revolutionary” discovery upends “this claim of mammalian uniqueness,” said Harvey Karten, one of the authors of the paper in PNAS.1
    While it may be humiliating to find such similarities with chickens, it is even more of a problem for Darwinists.  “But this kind of thinking presented a serious problem for neurobiologists trying to figure out the evolutionary origins of the mammalian cortex,” the article continued.  “Namely, where did all of that complex circuitry come from and when did it first evolve?”  The researcher could only offer “the beginnings of an answer: From an ancestor common to both mammals and birds that dates back at least 300 million years.”  The laminar and columnar properties of cells in the neocortex “evolved from cells and circuits in much more ancient vertebrates.”  Neither the article and the paper used the term “convergent evolution,” but the implication is inescapable: since, according to the paper, birds are on “a parallel branch to mammals on the evolutionary tree,” their resulting similarities must have come about by convergence.

1.  Wang, Brzozowska-Prechtl and Karten, “Laminar and columnar auditory cortex in avian brain,” Proceedings of the National Academy of Sciences, published online before print June 28, 2010, doi: 10.1073/pnas.1006645107.

This “explanation” conveys no information; it merely pushes the required Darwinian miracle farther down the Tree icon.  Now Darwinians have to envision some primitive vertebrate ancestor, a lizard perhaps, getting lucky to receive a mutation pregnant with possibilities.  Some day, that mistake would lead to the song of the nightingale and The Song of the Nightingale (Stravinsky).  This double convergence involved both the cells of brains and their ability to produce musical output.  As long as we’re talking miracles, might as well splurge.

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