1. Homework Questions
PG. 287
Q3: Explain why harmful mutations do not accumulate over time and cause harm to populations.
ANSWER:
Harmful mutations cause harm to the individual and evolution will select against individuals with harmful mutations. These individuals will not breed with others, causing the harmful mutation to disappear from the population.

2. Homework Questions
PG. 287
Q9: How do the genetic diversity of a population and mutation rates limit the ability of breeders to create organisms with desired traits?
ANSWER:
Hint: Think of the blue rose.
Breeders can only work with the genetic diversity that is already present in the organisms population. If a trait does not exist in an organisms genome, a breeder cannot just create that mutation. Mutations are random and rare. This means that beneficial mutations are unlikely to happen.

3. Homework Questions
PG. 319
Q28: What is artifical selection, and why is it called artificial?
ANSWER:
Artificial selection is directed breeding in which individuals that exhibit a particular trait are chosen as parents of the next generation. It’s called artificial because it is controlled by human choice, not by nature.

4. The Modern Synthesis: Evolution and Genetics

5. Charles Darwin - Born in Shrewsbury, England on February 12, 1809
- Born into a wealthy family as the 5th of 6 children
Grandfather, Erasmus Darwin, had proposed that all life came from a single organism, “the Great First Cause”
Darwin was encouraged to become a doctor, but was fascinated with the natural world

6. The Voyage of the Beagle
December 27, 1831, he joins the HMS Beagle as a naturalist on a five year voyage
The ship’s mission was to map the coast of South America for Britain
As a naturalist, Darwin was to observe and collect specimens

7. How did he begin to craft his theory of evolution?

8. Observations in South America
In Argentina, Darwin uncovered fossils of the Megatherium and Glyptodon
These fossils looked like giant sloths and armadillos
The fossils were found in the same geological range as these modern animals
Fossils of marine organisms also found in the Andes Mountains

9. Observations in the Galapagos Islands
Island chain 1000 km west of Ecuador
Discovered many new species with many similarities to species found on South America
No native amphibians or large land mammals
why?

10. Observations in the Galapagos Islands
Marine Iguana:
Closely resembles iguanas from the South American Mainland
Is the only known lizard able to dive and forage in water

11. Observations in the Galapagos Islands
Giant land tortoises
At least five unique species were found on different islands

12. Darwin’s Finches
Darwin at first thought they were one species with variation
13 species with distinct characteristics
Their beaks show variation in shape and size
Why?

13. Forming the Theory
After leaving the Beagle in 1836, Darwin spent more than 20 years gathering evidence on evolution
He knew that his theories would be controversial
By the time he presented his theory, Darwin was able to not only explain that evolution had happened, but also how it occurred…mostly

14. On the Origin of Species
By 1844 Darwin had prepared an essay on his theory of Evolution, but did not publish it
received a letter from Alfred Russell Wallace, who had also concluded that evolution must be true
This pressure led Darwin to publish his theory as On the Origin of Species in 1859

15. Backlash

16. Please read 294-295 and complete #1-4