Larson 10

test will be Wed:

• in class: open books/notes/internet, you may write on a laptop
• write one essay, roughly two double spaced pages
• question will be only on Larson
• there will be a choice of questions, one in each of two areas
  
• what outside forces shape science
• the changing fight between science and religion
  
• how to study for an open book test?
• some kind of cross-references between notes and book
  
• make a list of major issues and think what examples you might use
• but make sure to read the question carefully when you start the test and answer that
  
• paragraphs with topic sentences are important, sentence grammar and spelling less so if I can follow easily
• you must use references for quotes and paraphrases and very specific information.  examples:
  
• (Larson p. xx)
• (http://pammack.sites.clemson.edu/lec3210/larson10.html)
• (class notes to ch. 10)
• no bibliography needed
  
• open book, open notes, open internet, but test will happen even if the wireless is down
  

The Peppered Moth (above ) was seen at the time as an example of evolution, but could be explained by different theories of how evolution worked (the paragraph at the bottom of p. 221 and the top of 222 is a very useful summary of that)

The resolution of this is called The Modern Synthesis and was developed by J.B.S. Haldane, Ronald A. Fisher and Sewall Wright beginning in the 1920s.  It was needed because Mendelian genetics didn't instantly solve the problems with understanding the detail mechanism of evolution

• geneticists focused on mutations, and didn't pay much attention to natural selection
  
• biometricians (what became today's population biologists) focused on natural selection but tended to avoid the question of mutations
• study of variation, some understanding of mutations
  
• there were a lot of details that needed to be worked out to put the two together
• Darwinism plus Mendelian genetics equals evolution, but showing that mathematically takes working out a lot of details
  

Population biology: Haldane showed mathematically that a given frequency of mutation and level of selection (say black moths have a 50% higher survival rate than speckled moths) can cause the formation of a new variety (Haldane was an arrogant type and wrote that only the best one out of one thousand of the human population should reproduce)

Fisher (motivated by very narrow eugenics concerns) showed how gene frequencies would shift under natural selection.  The more benefit provided by a variation (allowing the animal to reproduce more), the more quickly it would spread.  Even though his motivations were deplorable, his science was good.
 (demonstration)

 Wright translate the statistics into an understanding of how new species could form from genetic drift in isolated populations. 

• Adaptive landscape: a way of modeling the fitness of a population
  
• What is also developing here is the ability to model the genetic complexity of large populations (before the invention of the digital computer)

Theodosius Dobzhansky published Genetics and the Origin of Species in 1937 pulled this together with real world examples to show that small scale genetic shifts can lead to evolutionary change on a large scale

The computer models could actually be matched to population studies in isolated situations such as the Galapagos islands



On islands where different species of finches co-exist, their characteristics are more separate

There is an interesting modern popular book on the finches The Beak of the Finch


Present day examples