1. Darwin’s Voyage of Discovery

2. Darwin’s Epic Journey
Charles Darwin- born in England on February 12th, 1809 (same day as Abraham Lincoln)
Born in a time of changing thoughts about the Earth and about life
Traveled the world in the HMS Beagle in 1831.
Developed a scientific theory of biological evolution that explains how modern organisms evolved over long periods of time through descent from common ancestors.

3. Darwin’s Ideas 1- Species vary globally 2- Species vary locally
3- Species vary over time

4. Flightless, ground dwelling birds
Vary Globally
Flightless, ground dwelling birds
Rheas – grasslands of South America
Ostriches- grasslands of Africa
Emu- grasslands of Australia

5. Vary Locally
Different, yet related, animal species often occupied different habitats within a local area.
Example- 2 species of rheas living in South America.
One in nice climate grasslands of Argentina
One in the colder, harsher grass and scrubland to the south.
Example- Tortoises of the Galapagos Islands

6. Darwin’s Finches
Collected finches with varying sizes of beaks

7. Vary over time Darwin Collected Fossils
He noticed that some fossils of extinct animals were similar to living species.
Example – Glyptodont vs. armadillo

8. Other Ideas that Shaped Darwin’s Thoughts
An Ancient, Changing Earth
Lamarck’s Evolutionary Hypothesis
Population Growth
Artificial Selection

9. An Ancient Changing Earth
Hutton and Lyell- Earth is extremely old and processes that changed the Earth in the past are still happening.
Examples
Volcanic eruptions- builds up
Erosion- tears apart

10. Lamarck’s Evolutionary Hypothesis
Suggested organisms could change during their lifetimes by selectively using or not using various parts of their bodies.
Also suggested that individuals could pass these acquired traits on to their offspring, enabling species to change over time.

11. WHICH ONES DID SURVIVE AND WHY?
Population Growth
Thomas Malthus- reasoned that if the human population grew unchecked, there wouldn’t be enough living space or food for everyone.
Leads to war, famine, and disease
Darwin realized this applied to other organisms in a more obvious way.
Maple trees- produce thousands of seeds. Most don’t sprout and of those that sprout, most don’t reach the age of reproduction.
WHICH ONES DID SURVIVE AND WHY?

12. Artificial Selection
We pick which traits we want passed on by only allowing those with the desired trait to reproduce.