1. Darwin: Natural Selection, & Evolution
Chapter 13

2. What you need to know!
How Lamarck’s and other notable predecessors’ views of the mechanism of evolution differed from Darwin’s.
The difference between structures that are homologous and those that are analogous, and how this relates to evolution.
The role of adaptations, variation, time, reproductive success, and heritability in evolution.

3. Preceding Darwin
Aristotle BC – Scala naturae: oragnization of life based on increasing complexity
Linnaeus – taxonomy: naming and classifying all organisms, binomial nomenclature: genus and species
Cuvier – father of paleontology, study of fossils leads to theory of catastrophism (mass extinction) which explains the boundaries between strata and the location of different species

4. Preceding Darwin
Hutton & Lyell – Theory of Gradualism (uniformitarianism): Earth geology changes slowly and continuously
The Earth must be VERY old
Darwin studied Lyell’s work

5. Preceding Darwin Lamark 1744-1829 – 1st theory of evolution
Use or disuse of body parts leads to their development or deterioration (acquired characteristics)
Inheritance of acquired characteristics

6. Charles Darwin Born in England in the 1800’s Went to college
Rich family
Went to college
Studied the bible
Sailed around the world studying life
Pictures, fossils, samples
Wrote the book: The Origin of Species
Father of Evolution by Natural Selection

7. Darwin’s Journey Darwin was fascinated by life
He wanted to learn about all different kinds
He sailed around the world in the mid 1800’s aboard the H.M.S. Beagle

8. Darwin
Video:
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9. The Galapagos Islands
It was in the Galapagos Islands that Darwin made his most famous observations

10. The Galapagos Islands Pinta Island Intermediate shell Hood Island Hood
Section 15-1
Pinta
Tower
Pinta Island Intermediate shell
Marchena
James
Fernandina
Santa Cruz
Isabela
Santa Fe
Hood Island
Saddle-backed shell
Floreana
Hood
Isabela Island
Dome-shaped shell

11. Darwin’s Finches
Darwin gathered many finches from all the Galapagos Islands
He noticed that each finch from each island was slightly different
They have a beak best suited to eat the food available on their island

12. Darwin’s Finches

13. Artificial Selection (Selective Breeding)
Darwin modeled natural selection after artificial selection:
Humans choose which traits they like and use selective breeding to manipulate the traits

14. Evolution by Natural Selection
Individual organisms differ, and some of this variation is heritable.
Organisms produce more offspring than can survive.
Because more organisms are produced than can survive, organisms compete for limited resources.

15. Evolution by Natural Selection
Individuals best adapted to their environment survive and reproduce most successfully. These organisms pass their heritable traits to their offspring.
Species alive today are descended with modification from species that lived in the distant past. If you go back far enough all life on this planet is linked in one great tree of life.