Heart of Dimness – Part 12

CreationMuseum-03

This is the 12th of a continuing series. I’m reviewing items from David Buckna’s post on the Truth.Origin Archive. I previously covered his item 9. Here’s item 10:

10. Evolutionists say mutation, migration, genetic drift, and natural selection produced new life forms. Why then are there so few examples–if there are any at all–of mutations building brand new organs?

Some evolutionists point to a study (2008) of Italian wall lizards (Podarcis sicula). From the abstract: “Here we show how lizards have rapidly evolved differences in head morphology, bite strength, and digestive tract structure after experimental introduction into a novel environment.” The study mentions cecal valves–muscles between the large and small intestine–that “slow down food passage and provide for fermenting chambers, allowing commensal microorganisms to convert cellulose to volatile fatty acids.” (A. Herrel et al., “Rapid large-scale evolutionary divergence in morphology and performance associated with exploitation of a different dietary resource,” Proceedings of the National Academy of Sciences USA 105 (12) (2008): 4792–4795.)

http://www.pnas.org/content/105/12/4792

But anatomist David Menton noted the original lizards had the ability to digest plant material; they simply preferred insects for roughly 95 percent of their diet. Menton added: “The ‘new’ muscular valve they found between the small and large intestine is simply an enlargement of muscles already present in the gut wall at this juncture.” So, far from being a truly new feature, the shift in available food allowed lizards with larger muscles at the juncture to be more successful at feeding and reproducing.

The “rapidly evolved” cecal valves are possibly just natural selection acting on pre-existing genetic information, helping a population adapt to its surroundings.

http://www.answersingenesis.org/articles/2009/06/06/news-to-note-06062009

The reader is invited to review the paper published by Anthony Herrel et al. It describes a development that occurred over a 36-year period, far shorter than the time spans involved in the study of fossils. That the degree of adaptation observed is so slight should not be surprising. Further, David states:

The “rapidly evolved” cecal valves are possibly just natural selection acting on pre-existing genetic information, helping a population adapt to its surroundings.

In all likelihood, this is exactly what has happened. However, it’s incumbent on David and others making such claims, to demonstrate some evidence. Such research would include:

  • Demonstrate there is nothing in the genome of the latest lizards that was not in the genomes of the starting population.
  • If there are novel genes, demonstrate these are not associated with the new capabilities.
  • On the other hand, anybody proposing that novel genes are responsible for the new capabilities will be required to demonstrate the association.

The illustration below is from the Anthony Herrel paper.

Fig. 4. Photographs illustrating the cecal valves in a male (A), a female (B), and a hatchling (C) P. sicula from Pod Mrčaru. Note the thick cecal wall and pronounced ridges. The arrow in C indicates the position of the cecal valve in a hatchling as seen from the outside.

Fig. 4.
Photographs illustrating the cecal valves in a male (A), a female (B), and a hatchling (C) P. sicula from Pod Mrčaru. Note the thick cecal wall and pronounced ridges. The arrow in C indicates the position of the cecal valve in a hatchling as seen from the outside.

David starts by asking a question:

Why then are there so few examples–if there are any at all–of mutations building brand new organs?

Then he proceeds directly to an example of extremely rapid adaptation. The real answer to his question lies in the fossil record, which covers the time scale for such events. I have previously referred to fossil evidence for the development of the mammalian ear:

probain_skull

joints

Like birds, crocodiles, turtles, snakes, lizards, amphibians, and most fishes, the earliest synapsids had a bone in the back of the skull on either side called the quadrate that made the connection with the lower jaw via a bone called the articular. But mammals today, including humans, use two different bones, called the squamosal and the dentary, to make this connection. How did this new jawbone configuration evolve?

For reasons we don’t fully understand, several lineages of synapsids — including the one that would eventually give rise to the mammals — began to evolve changes in the jaw joint. Originally the quadrate and articular bones formed the jaw joint, but these synapsids (e.g.,Probainognathus) evolved a second pair of bones involved in the jaw articulation. The squamosal bone was positioned alongside the quadrate in the upper jaw, and the dentary was positioned alongside the articular in the lower jaw.

The example is from “Jaws to ears in the ancestors of mammals” on the UC Berkeley site.

David further invokes the pronouncements of creationist David Menton:

Dr David Menton

Creationist Anatomist

Answers in Genesis USA

Biography

Professional Affiliation

  • Biomedical research technician at Mayo Clinic, Rochester, Minnesota in the Department of Dermatology (1960–62)
  • Associate Professor of Anatomy at Washington University School of Medicine, St. Louis, Missouri (1966–2000)
  • Associate Professor Emeritus of Anatomy at Washington University School of Medicine (July 2000)

Professional Activities

  • Former guest lecturer in gross anatomy
  • Former coursemaster of Microscopic Anatomy at Washington University School of Medicine
  • Former consulting editor in Histology for Stedman’s Medical Dictionary, a standard medical reference work

Extraprofessional activities

  • Vice-president of Congregation of Faith Lutheran Church of Ballwin, Missouri
  • Sunday school teacher for high school students
  • Former president of the Missouri Association for Creation, St. Louis, Missouri
  • Technical Advisor for the Institute for Creation Research in Dallas, Texas
  • Lectured throughout the United States and Canada on the Creation-Evolution controversy

Education

  • B.A. from Minnesota State University in Mankato, Minnesota
  • Ph.D. in cell biology from Brown University

Of course, a Ph.D. in cell biology from Brown University is worth noting. While there is nothing in his resumé indicating he ever did serious work related to evolutionary biology, his right to comment is not denied. However, as I mentioned before, this point has little that relates to whether biological evolution can develop new organs. David is going to have to propose some serious challenges before I can take him seriously.

In a future post I will cover David’s item 11. Keep reading. And may Jesus have mercy on your soul.

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One thought on “Heart of Dimness – Part 12

  1. Pingback: 44 Reasons Why Evolution Is Just A Fairy Tale For Adults | Skeptical Analysis

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