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S.J. Gould

T.H. Morgan’s view of Mendelism eventually strongly promoted by S.J. Gould and others as punctuated equilibrium VS gradualism (biometrics) (What’s wrong with both?). S.J. Gould.

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S.J. Gould

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  1. T.H. Morgan’s view of Mendelism eventually strongly promoted by S.J. Gould and others as punctuated equilibrium VS gradualism (biometrics) (What’s wrong with both?) S.J. Gould

  2. Muller showed that you could induce a high rate of change in a trait by radiation – the engine that natural selection uses again gets a boost for big qualitative changes Muller

  3. BUT! THE BIG CONCEPTUAL FUZZINESS CONTINUES Quantitative and Qualitative Traits!

  4. This trait stuff is all fine and good but what are these units of inheritance things that Mendel was talking about and Bateson called genes? If we found them we might find how they change. Sutton TOP SUSPECTS: CHROMOSOMES BOVERI/ SUTTON THEORY But chromosomes are both protein and nucleic acids 1937 Avery McCleod McCarty showed genes are DNA: So, genes must transmutate to provide trait variability Avery Darwin’s explanation is pretty solid now But The biometric/Mendel debate continues – quantitative or qualitative trait changes? I WANT TO EMPHASIZE THIS POINT TO REMEMBER ANDHow to separate genes (DNA) to show they change - they are chemically too similar

  5. In 1953 Franklin/Watson/Crick provided structure of DNA – the clue to replication – Darwin keeps looking better. Franklin Niremburg and Khorana deciphered the genetic code (bases of errors – mutations) Berg/Cohen/Boyer first recombinant gene How to separate genes Niremburg Gene Sequencing came of age – Fred Sanger – sbys now allows 100 MB/day or much more Khorana Sanger Berg Cohen Boyer

  6. Large sequence comparisons found: too much is the same One book of info to make a plant - one book to make a human STUNNING Where are the new genes as evolution progresses to more and more complex organisms? IT MUST BE GENE EXPRESSION We think now that environment induced diversity is due largely to differential gene expression. We continue to embrace this concept to explain how the environment can induce trait changes that are normally not passed to the next generation (e.g. vernalization). But is this just another (comfortable) tempting thought? Herein lies a tempting explanation of qualitative and quantitative traits?

  7. How can traits be qualitative vs quantitative based on expression? Qualitative genes are Master genes – big effect that control expression of many quantitative target gene – small effect How did we get into the gene expression business?

  8. Gene Expression History COT Curves Regulation of Structural Gene Expression in Tobacco Joseph C. Kamalay and Robert 8. Goldberg Department of Biology University of California Los Angeles, California 90024 Cell, Vol. 19, 935-946, April 1980 Goldberg Northern Blots Subtraction library/differential expression/SAGE, etc. Microarray – chip era Massive parallel signature sequencing Abiotic stress induces 3500 genes E trait/Networks/Genome wide association mapping

  9. PHENOTYPE (TRAIT) GENES Genes for stress resistance evaluated in transgenic mutant plants – updated Dec. 27, 2008, http://plantstress.com 84 - Genes encoding enzymes that synthesize osmotic and other protectants 13 - Late embryogenesis abundant (LEA) related genes 197 - Various regulatory genes 23 - Hormone regulating genes 53 - Oxidative stress related genes 31 - Genes encoding for molecular chaperones & other proteins 66 - Genes encoding proton pumps, anitporters and ion transporters 18 - Others Total: 485 Master type genes 286 What is the definition of tolerance (many traits – remember we define trait) Many small effects (Quantitative) what about Qualitative – (Bottlenecks and Gene Pool)

  10. Some Examples of the Many in Arabidopsis

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