Examples of structures that have been proposed as irreducibly complex
Bacterial flagellum See Illustration on next slide. . .
Matzke, N. J. (2003). Evolution in (Brownian) Space: a model for the origin of the bacterial flagellum. Retrieved December 8, 2008, from http: //www. talkdesign. org/faqs/flagellum. html
The eukaryotic cilium • Whip like structure found in most eukaryotes – Very complex – 9+2 microtubule arrangement – Many additional protein parts – Used for movement and locomotion
The eukaryotic cilium • Evolutionary simpler forms found in many different organisms: • Simpler can easily be functional. Figures from Finding Darwin’s God, Kenneth R. Miller, 1999, New York, Perennial
Blood Clotting “… none of the cascade proteins are used for anything except controlling the formation of a clot. Yet in the absence of any of the components, blood does not clot, and the system fails. ” (DARWIN’S BLACK BOX, Behe p. 86). Eliminate Factor XII Whales & dolphins lack Factor XII - and their blood still clots.
Blood Clotting “… none of the cascade proteins are used for anything except controlling the formation of a clot. Yet in the absence of any of the components, blood does not clot, and the system fails. ” (DARWIN’S BLACK BOX, Behe p. 86). Whales & dolphins lack Factor XII - and their blood still clots. Puffer fish lack the entire contact system and their blood still clots.
Immune System Evolution Between 1996 and 2005 each element of the transposon hypothesis” of immune system VDJ evolution was scientifically confirmed. Kapitonov & Jurka (2005) RAG 1 Core and V(D)J Recombination Signal Sequences Were Derived from Transib Transposons. Public Library of Science, Biol. 3: e 181. .
Emotional Investment • “Professor Behe was presented with – fifty- eight peer-reviewed publications – nine books – several immunology textbook chapters about the evolution of the immune system • he simply insisted that this was still not sufficient evidence of evolution, and that it was not “good enough. ” (23: 19 (Behe)). ”
Is Body Design Intelligent? • Recurrent laryngeal nerve – Goes from the brain through a tube near the heart to the larynx. – One of the cranial nerves • Direct route in fish. • Detour of ~ 1 -2 feet in humans. • 10 -15 feet of extra nerve in giraffes. • Why? • Because evolution and natural selection operate in the short term, with each step taking place as a modification of what is already present.
Grateful Acknowledgements Ms. Cynthia Curtis – IB Biology Teacher GHS Pia Vogel Ph. D – Associate Professor in Biology SMU John Wise Ph. D - Lecturer in Biology SMU Randall Scalise Ph. D – Senior Lecturer in Physics at SMU Mark Pallen Ph. D - Professor of Microbial Genomics, Centre for Systems Biology Biosciences at the University of Birmingham Kenneth Miller Ph. D – Professor of Biology, Royce Family Professor for Teaching Excellence, Brown University
Mollusk Eye Evolution • Five different eye forms found in mollusks – “Gradations from complex to very imperfect and simple”. • Lens material is “housekeeping enzyme. • Pathway from a simple light absorbing pigment to a complex cameralike eye is well worked out. From - Evolutionary Analysis, 4 th ed. Scott Freeman and Jon Herron
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