1/17- What is science?- Scientific method- Are science and religion incompatible?- Why is evolution so controversial?“we are entitled to opinions but not facts”Truthiness: -truth comes from the gut, not books - quality of preferring concepts or facts one wishes to be true, rather than concepts that are actually true.What is science?- A body of knowledge and methodology - A way of knowing- Falsifiable- can only hope, not disprove- Creates predictions- Incremental & cumulative (sequencetial)- Collaborative process- Self-correctingThe scientific methodInductive: observation  pattern  tentative  theoryDeductive: theory  hypothesis  observation  confirmationScience…- cannot make statements about the supernatural world- is not incompatible with religion - is likely incompatible with fundamentalism & literal interpretations of religion1/24How does evolution work? -evolutionary forces or process? --natural selection -- mutation -- gene flow --genetic drift1- differential variation in traits2-reproduction- some traits are genetic, some aren’t 3- traits have to be inheritableNatural selection provides directional change in allele frequency in response to environmental condition -works on the phenotype (what you see/what presents) -you reproduce, or you dieWhat is fit? “Survival of the fittest”Different kinds of natural selection? -different alleles of genetic material through time- directional selection: shifts the mean of the population. Favors a particular extreme- stabilizing selection: centers the mean of the population- disruptive selection: selects for 2 or more population means and eventual speculation. Splits. - Balancing selection: different alleles are supported in a population. Selection for heterozygosity that protects against a disease i.e. sickle cell anemiaSexual selection: -helps find mates quickly and easily i.e.  peacocks and their tail feathers- can also be a problem, helps you stand out to predatorsMutation- only way new things occur- Permanent change in DNA- Random, new, rare- Occur consistenly- Important to evolution if inheritablr- Beneficial, naturalGene flow: genetic inheritance between populations. Migration of fertile individuals, or from transfer of gamets. Within a population, introduction or reintroduction of genes, increasing variation.Intelligent design on trial-how is science different from religions faith-how does separation of church and state figure in this debate?1/31Charles Darwin (1908-1882)- Comes from family of wealth, grandfather set the tone of family of intellectuals. English family- Lousy student- Early passion for collecting and natural history.- Neither an atheist or fascist. Actually wanted to be a part of the Church of England. - Alfred Wallace. The 2 of them were working on the same problem at the same time. They shared ideas/manuscripts via the post, it became clear to Darwin to get his book out or Wallace was going to beat him. The Voyage of the Beagle (1831-1836)- Hired on by the captain to be a “witty dining companion”.- Over time he became a naturalist.- A lot of the trip focused on south America, he studied fossils he found in south America and compared them to animals living in south America/Australia/the islandObservations of Darwin’s Voyage:- Biological richness of tropical forests and islands that differ from Europe.- Fossils related to living animals in same area with some continuity in characters-ground sloths and living sloths. He found jaw of giant 100 lb ground sloth, compared it to other fossils and found similarities.-glyptodont and armadillos- He also worked with finches. Galapagos finch. Different ecologies that finches can survive but not all with survive since they are competing for the same food source. As time went on beaks adapted to different kinds of diets so they weren’t competing anymore. Seed eating finch was the first, then over time 14 different species of finches evolved.- Succession of types, representative types, similar yet different/island proximity.Darwin’s Development of the Theory of Natural Selection- He looked at how animals and plants were different but came from the same ancestoral lines- Began to accept species are not fixed. Something is happening to bring change. Adapting and changing- Payed attention to artificial selection. There is no divine “sending things in a direct selection”- Adaptations are not perfect. Some have advantages, some don’t. - There is a competition for resources. Species have to live on limited resources- Natural variation is inherit. - Individuals with favorable characteristics (for that nitch) survive at higher rates to pass these on to their offspringThomas Huxley, big supporter of Darwin. Samuel Wilberforth (soapy same, because he was slippery in debates) was a bishop of oxford. The 2 got into a debate about the theory of evolution. -“I would rather be the offspring of 2 apes then be a man and afraid to face the truth” –HuxelySome Initial Challenges to Darwin1. Evolution of complex structures?2. Intermediate forms in the fossil record?3. How does heredity work?How could initial forms of a complex structure be adaptive? -I.e. the human eye, how does this evolve? Darwin followed with a proposal for what he thought were the intermediate levels for the development of the eye. The existence of transitional forms: -i.e. the whale evolution. Found that there are mammals that once swam and walked on land. In 2006, we found tiktaalik, 375 million years old, found that it had beginnings of shoulder joint, lungs and heels. Theory is it was a water dweller and a land dweller.Evolution in Action 1 Industrial Melanism and the Peppered Moth- Dark colored moths increased to 90% in industrial Britain in the 1800s. Before the revolution there was a greater population of light moths, camouflaged with the light colored trees. During the revolution the trees got covered with soot, so then the dark colored moths were favored. They had traits that allowed them to pass on their genetic material.Evolution in Action 2 Finches on Daphne Island, Galapagos- Finches have evolved to have a smaller beak since they are all competing for the same food source. Evolution in Action 3 Darwinian Medicine- Vector spread and casual contact. -Alfred Russel Wallace (1823-1913)- English- Come from a poor family, left school at 13 cause they couldn’t afford it- In 1848, went on a trip to Brazil. Spent