the Final...❖ Paper pathsPaper paths

❖ The Big Ideas from the papers we’ve read The Big Ideas from the papers we’ve read

❖ Big picturesBig pictures

❖ How hemoglobin How hemoglobin worksworks

❖ How hemoglobin & opsin How hemoglobin & opsin evolveevolve to ‘do new to ‘do new things’things’

❖ How do we draw conclusions (experimentally, How do we draw conclusions (experimentally, logically)logically)

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Permission to concludePermission to conclude

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What’s a ‘scientific argument’

❖ NOT: two people shouting at each otherNOT: two people shouting at each other

❖ IS: an exchange of IS: an exchange of defensibledefensible positions, backed by positions, backed by evidenceevidence & & logiclogic

❖ core claims/conclusions must be core claims/conclusions must be confrontedconfronted using using evidence and logicevidence and logic

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The myth of ‘two sides’

❖ Just because there exists one data-backed point of Just because there exists one data-backed point of view doesn’t mean there is a valid, compelling view doesn’t mean there is a valid, compelling alternate viewalternate view

❖ Just because you found someone with an Just because you found someone with an underrepresented point of view doesn’t mean underrepresented point of view doesn’t mean they have something meaningful to saythey have something meaningful to say

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Any problems with the logic?

❖ All toasters are made of goldAll toasters are made of gold

❖ All items made of gold are time-travel devicesAll items made of gold are time-travel devices

❖ ThereforeTherefore all toasters are time travel devices all toasters are time travel devices

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http://people.umass.edu/klement/100/logic.html

Duh—we’re at the center

❖ IF IF the Earth were moving at 67,000 miles/hour* the Earth were moving at 67,000 miles/hour* around the Sun, we’d feel itaround the Sun, we’d feel it

❖ We don’tWe don’t

❖ It must be the Sun that’s moving, not the EarthIt must be the Sun that’s moving, not the Earth

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http://www.scientificamerican.com/article.cfm?id=how-fast-is-the-earth-mov

Sometimes logical argument matters… or used to

❖ Lincoln*: I state in syllogistic form the argument:Lincoln*: I state in syllogistic form the argument:

❖ Nothing in the Constitution . . . can destroy a right distinctly Nothing in the Constitution . . . can destroy a right distinctly and expressly affirmed in the Constitution.and expressly affirmed in the Constitution.

❖ The right of property in a slave is distinctly and expressly The right of property in a slave is distinctly and expressly affirmed in the Constitution.affirmed in the Constitution.

❖ Therefore, nothing in the Constitution can destroy the right Therefore, nothing in the Constitution can destroy the right of property in a slave.of property in a slave.

❖ Lincoln, in refutation:Lincoln, in refutation:

❖ ““There is a fault [in the argument], but the fault is not in There is a fault [in the argument], but the fault is not in the reasoning; but the falsehood in fact is a fault of the the reasoning; but the falsehood in fact is a fault of the premises. I believe that the right of property in a slave is premises. I believe that the right of property in a slave is not distinctly and expressly affirmed in the Constitution.”not distinctly and expressly affirmed in the Constitution.”

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http://highered.mcgraw-hill.com/sites/dl/free/0073386677/610543/Moore9e_ch02.pdf

*5th Lincoln-Douglas debate

To argue fruitfully…❖ We must We must agreeagree on the PREMISES on the PREMISES

❖ If If youyou think the purpose of college is to make think the purpose of college is to make everyone smarter/more thoughtfuleveryone smarter/more thoughtful

❖ And And II think its purpose is to identify the smart & think its purpose is to identify the smart & capablecapable

❖ We cannot have a productive argument about We cannot have a productive argument about who to let in, how to grade, how to spend who to let in, how to grade, how to spend classroom timeclassroom time

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If

❖ If all observed instances of a phenotype arise from If all observed instances of a phenotype arise from a single type/identify of mutationa single type/identify of mutation

❖

❖ THENTHEN it is reasonable to conclude that there was a it is reasonable to conclude that there was a singlesingle origin of that mutation/phenotype origin of that mutation/phenotype

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❖ IF there are many other ways of achieving the phenotype

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http://www.popularmechanics.co.za/sci-tech-news/dna-building-blocks-can-be-made-in-space/

Correlation v. Causation11

http://i.imgur.com/J6jPzNv.jpg

(unexamined linkages)

Molecular clock…12

(chimpanzee sequence)

Human

Blue: nte, position

Circle: large group of people

Red: causes LP

Green: digesters

# of mutations = amount of time???

Ticking premises❖ Suppose we wanted to ‘count ticks’ to find the Suppose we wanted to ‘count ticks’ to find the

common ancestor of you & E. colicommon ancestor of you & E. coli

❖ How many ways can you think of in which the How many ways can you think of in which the passing of genes from one generation to the passing of genes from one generation to the other of your species vs. E. coli would throw off other of your species vs. E. coli would throw off our measurement of ‘clock ticks’ [mutations our measurement of ‘clock ticks’ [mutations that differ between 2 organisms]that differ between 2 organisms]

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