1/ 23/ 2012

Today we began our evolution unit. We:

• Recieved the scedule, UP, notes, Darwin packet, and lab 38
• Watched video clips about evolution
• Answered the questions on UP 7-8 (see below)

You can view the videos at: http://www.pbs.org/wgbh/evolution

Then type the video titles in the convenient little search box in the top- right corner of your screen, and find the link to the video. Note: You need quicktime to see the videos, and the subtitles are really useful!

Video 1: Isn't Evolution Just a Theory?

Question: Is it correct to say that evolution is JUST a theory?

Key Points:

• Charles Darwin pioneered the idea that all life is connected, and the theory of natural selection
• Theories pull together observations to create "rules" for how the universe works

Video 2: Who was Charles Darwin?

Question: Why was Darwin considered a "Revolutionary"

Key Points:

• Darwin's work was highly controversial because it contradicted many established religious and scientific beliefs at the times
• In order to prove his theories, he traveled the world and carefully documented life's great diversity, then analyzed the patterns

Video 3:How do we know that evolution happens?

Question:Describe the transitional fossils associated with whales.

Key Points:

• The evolution of species can be plotted on an evolutionary timeline, which chronologically shows the changes ancient species went through in order to evolve into modern species
• An ancient species that shares common traits with a modern one, and has no similar, discernable ancestors, may be the original ancestor to modern species
• As time passes, the ancestor changes and adapts and become more similar to modern species

Video 4:L How does evolution really Work?

Question: Describe the process of natural selection and how it effects hummingbird populations.

Key points:

• Genetic Variation: different individuals within a species express different traits, some more favorable than others
• Overproduction of offspring: more offspring are produced than the number that can survive
• Struggle for existence: The overload of individuals compete for resources
• Differential survival and reproduction: Individuals without favorable traits are at a disadvantage for obtaining necessary resources. These individuals die. Those left have more favorable traits and have a higher chance of reproduction, so the favorable traits are inherited by the next generation.

Video 5: Did Humans Evolve?

Question: Explain how DNA sequences are used to provided eveidence of a commoon ancestor?

Key points:

• Humans did not eveolve form chimapnzees, but both species shared a common ancestor
• Humans and primates have similar DNA, which helps prove this relationship
• If two species share the same gene sequences, aside from a few mutations, they are related
• Physical trait similarities, fossil evidence, and DNA similarities prove common ancestry

Video 6: Why does evolution matter now?

Question: Why is the theory of evolution an important theory for doctors and the field of medicine? How does the theory affect the way illnesses and treatments are approached?

Key Points:

• Some microbes can evolve to become resistant to antibiotics, which is very dangerous
• If one drug does not kill ALL of the microbes, the remaining resistant microbes reproduce and form an entire population of microbes resistant to a drug. Thus, they have evolved to evade our killing, which can result in difficult to cure diseases.
• In result, multiple drugs are often prescribed

Homework is on Google Docs (hint- read chapter 13, chapter 1 p. 8-13, the Darwin packeet, and begin on UP 5)

Meet in computer lab tomorrow!!!!!!!

Maddy is the next scribe