02/03/06

Notes from 02/03/06

Last lecture main points
- There were lots of ideas before Darwin's
- Enlightenment made us learn by looking around

Lamarck was an orthogenesis propoent: believing that objects were reaching perfection by an internal force.

Got his undergrad in theology
Published Origin of Species in 1859
Floated through school
Met John Edmonstone (a free black) who taught him taxidermy
Fitzroy (captain of the Beagle) was mental and cut his own throat because he blamed himself for Darwin's theory
3 Important visits of the Beagle

Santiago: Darwin noted chalk sea-fossils 45 feet above sealevel; realized the world changes a lot
Patagonia: finds huge sloth size of an elephant --uknown to science; proves extinction occurs
Falkland islands: finds animals that are like those from Europe but slightly different

Galapogos:
- more rain = taller plants = tortoise has to reaach higher to get food = higher shell
Darwin read lots of stuff and was influenced by many scientists on the Beagle.
- Cuvier showed him about gradualism
- Lyell's "Principles of Geography" showed him the true age of Earth
- Buffon ???
- Malthus's essay on population showed him about the necessity of struggle for natural selection to work
Darwin needed to realize exponential growth to formulate evolution by natural selection. In October of 1838 he read Malthus's essay on population
Two theories why Darwin didn't publish
- He respected Lyell and wanted lots of evidence
- He was scared of all the talk it would bring about
Wallace and Darwin co-publish in the Linaen Society
- President said about the year in review: there were no "striking discoveries"
- Darwin had written travelogue for the common peoples so he had some pull in the common media. So he published Origin of Species for the common.
Darwin's theory: see Origin of Species

Artificial selection: when man chooses which phenotypic traits to allow to contribute most to the next generation. A useful example for the proof of evolution was the artificial selection humans had been carrying out on crops and livestock and domesticated animals.

Homology: common traits because of common ancestry; demonstrates branching process of evolution. Linnaeus would have called this reaching a perfect design.

Analogy = convergence = common traits but not by ancestry; just that the two animals converged on the same answer to similar challenges. Lamarck would have said that they had an internal drive and are pushing to the same place.

Biogeography: Thylocenes in Autrassia, wolf in Americas and Europe; this shows that though they were separated, the fittest solution made it on to survive and reproduce. Descent from a common ancestor explains distribution of ancestors.