Lecture 9. Darwin's Insights Flashcards
What are three things you could say about life ?
- Amazingly diverse
- Mostly bacteria and insects
- Largely unknown
What is unique to living things ?
Design for purpose
How could you say animals arose ?
A selective, cumulative process
What part does chance play in animal arisal ?
Only a small part
In what form does chance take in the animal arisal ?
Mutations
What proof is there that poor design in of animals ?
The vertebrate eye, light comes in through all the wiring and not from the side where the receptor cells are
What questions did Charles Darwin consider for his entire life ?
- Why is there life on earth?
- Why is life on earth so diverse?
- Why do living things appear to be designed?
- Why does some of that design that appear so poor ?
What did Plato suggest and Aristotle support ?
Essentialism
What is essentialism ?
All objects have a substance that makes the thing what it is, and without which it would be not that kind of thing
What did Louis Agassiz argue ?
That species were fixed, reflecting the mind of the creator
What did Carl Linnaeus, Jean-Baptiste Lamark and Erasamus Darwin question ?
The immutability of species
Who classified living things ?
Carl Linnaeus
How did Carl Linnaeus naming system work ?
It was a 2 part names for genus and species
What did Carl Linnaeus recognise ?
A hierarchical phylogeny
What did Erasamus Darwin contain ideas about ?
- Common descent
- Heritability
- Survival of the Fittest
- Struggle for Existence
- Evolution
What did Georges Cuvier believe in ?
Catastrophism
What is catastrophism ?
The theory that changes in the earth’s crust during geological history have resulted chiefly from sudden violent and unusual events
What did James Hutton believe in ?
Gradualism
What is gradualism ?
Small apparently weak forces eg. river could given enough time have huge geographical effects eg. canyon
What did Charles Lyell believe in ?
Uniformitarianism
What is uniformitarianism ?
All geological processes ever existing are still going on
Who suggested evolution by vertical speciation ?
Jean Baptiste Lamark
What are the two forces suggested by evolution by vertical speciation ?
- Complexifying force
2. Environmental force
What is the complexifying force in evolution by vertical speciation ?
Driving organisms up a ladder of complexity from single cell infusorian towards more complex species
What is the evolutionary force in evolution by vertical speciation ?
Adapted them to local environments through use and disuse of characteristics. Regularly used organs got stronger, disused one disappeared
What did Thomas Robert Malthus believe ?
Principle of population
What is the principle of population ?
The human population will increase exponentially (2,4,8,16) but the food supply increases arithmetically (1,2,3,4). The population will thus eventually exceed the food supply, until famine, war or disease will restore the balance
What did Alfred Russell Wallace believe in ?
Transmutation of species
What is the transmutation of species ?
Species changing into different species
What were Darwin’s and Wallace’s insights ?
- Horizontal speciation
- Gradualism
- Common descent
- Man as an animal (not Wallace)
- Natural selection
What is horizontal speciation ?
When two species could both have evolved from the same ancestor by a split in the evolutionary line
What is Darwin and Wallace’s thoughts on gradualism ?
Speciation happened gradually not a sudden change to a new type
What is common descent ?
All life could have one single ancestor
What did Darwin believe about natural selection ?
That it is the mechanism of evolution
