Lecture 3 - Evolution Flashcards
Define the teleological argument and what teleo means
- Complex functionality = intelligent design/divine creation
- Teleo = end result
Who argued the teleological argument and what example did he use?
- William Paley = 18th century philosopher and theologian
- If you find a watch ‘existing’ = created not by chance
What is the evolutionary argument?
Complex structures from random chance as part of natural selection = successive mutations with best fit chosen each time
Which 3 men proposed the evolutionary argument?
- Richard Dawkins’ book ‘the blind watchmaker’
- Alfred Wallace and Charles Darwin’s paper written tog after independent findings
What is evolution and it’s key mechanism?
Descent/inheritance/successive generations with modification by natural selection
Define natural selection
Differential survival and reproduction of individuals from differences in phenotype
What are the 4 things needed for natural selection?
- Variation = different traits
- Differential fitness = traits increase survival/reproduction
- Inheritance = traits passed from parent to offspring
- Adaptation = advantageous traits more common over generations
Describe how peppered moths are an example of evolution
- Black/melanised and white/unmelanised forms
- Industrial revolution = soot = black moths successful
- Clean air legislation = white moths successful
Describe how Darwin’s finches, as studied by the Grants, is an example of evolution
- Different beak shapes = different food (speciation from common ancestor)
- Drought = no small seeds = large beaks successful
- Flooding = small seeds = small beaks successful
Describe how Trinidadian guppies studied by John Endler are an example of evolution
- Sexual dimorphism = trait differences between sexes
- Guppies below waterfall = high predation = less colourful
- Guppies above waterfall = less predation = colourful
- Move below guppies to above = colourful after 4yrs/12gens
How is lactase persistence an example of contemporary evolution in humans? Are there any exceptions?
- Babies have lactase by LCT gene switched on -> weaning switches it off
- Agricultural revolution = nutrient rich milk = LCT ‘on’ mutations successful = 90% tolerant
- Exceptions in populations with fermented milk products converting lactose
Describe the impact of antibiotics on bacterial evolution
Antibiotics = selection pressure = those that survive by random mutations resistant = more resistant over time
