1. Bellwork: What do you think of when you hear the term evolution
Bellwork: What do you think of when you hear the term evolution? What do you know about Charles Darwin and his work?

2. Darwin’s theory of evolution
Section 16.1 – his voyage of discovery

3. Charles Darwin One of the most famous British scientists of all time
Born in 1809
Exciting time for science – humanity understanding of the Earth was changing
Evolution refers to the idea of changes over time
Darwin developed a scientific theory that explains how modern organisms change over long periods of time through descent from common ancestors

4. Darwin’s journey
Darwin sailed on a 5 years voyage of the Beagle in 1835
Plan of journey was to map the coastline of South America
Darwin was a naturalist – planned to collect specimens of plants and animals
He had no idea that he would have a scientific breakthrough that would change our understanding of how the world works
His research has implications for the modern day
Living world constantly changing
How drug resistant bacteria come about
How diseases such as Avian flu evolve

5. Observations aboard the beagle
Darwin was a geologist
He was also a lover of all things natural
He collected 68 species of beetles in a single day trip to Brazilian rainforest
He made detailed observation in his notebook, but didn’t stop there
He wanted to explain why there was so much biological diversity in a scientific way

6. Darwin’s key observations (#1)
Species vary globally
Darwin noticed that different, yet ecologically similar animal species inhabited separately, not ecologically similar habitats around the globe
Example – Rhea (South America), Ostrich (Southern Africa) and Emu (Australia)
Rabbits found in grassland in Europe, but not South America or Australia despite having ideal habitats for them
Why are kangaroos only found in Australia?

7. Darwin’s key observations (#2)
Species vary locally
Darwin noted that different yet related animal species often occupied different habitats within a local area
Many examples from the Galapagos islands
Islands are very close, but they have different ecological conditions
Different islands have animals that have specific characteristics
Tortoises are famous, but also finches and other birds display variation

8. Darwin’s key observation (#3)
Darwin also collected fossils, not just living specimens
Scientists already knew that fossils preserve remains or traces of ancient organisms
Some looked very strange, others look like modern organisms
Example – Glyptodont (ancient giant armored mammal)
Found in same region that armadillos presently found in
Was there a connection?

9. Darwin’s explanations
Darwin discovered that each of his finches he collected from the Galapagos were different species of finch, found nowhere else in the world
Same applied to tortoises – each island had a unique species of tortoise
Although all species on the Galapagos looked like, and were related to a species found on the South American mainland
This lead to a lot of research, culminating in his theory of evolution, and the idea that species are not fixed and that they can change by some natural processes