Monday, April 18th

Objectives: • Explain how biological evolution is the consequence of the interactions of

genetic variation, reproduction and inheritance, and natural selection and time.

• Explain how multiple lines of scientific evidence support biological evolution

Remember to take the genetics test at lunch or after school if you need to make it up

Agenda:1. Unit overview2. Darwin vs. Lamarck3. Wallace Jigsaw4. Cartoon Activity

Day 1

Unit overviewYou will be able to……compare and contrast the theories of evolution developed by Lamarck and Darwin…evaluate different types of evidence evolution (biogeography, fossils, homologous structures, vestigial organs

and DNA) …explain how scientific knowledge can change in light of new evidence…design a scenario resulting in natural selection and predict its effect on a population of organisms…address arguments concerning common misconceptions regarding the theory of evolution

We will be able to answer these questions:• Why is there so much diversity of life on Earth?• How do we know evolution occurs?• What do you need for evolution to take place?• How can we explain why there are fossils of organisms that aren’t alive today?

Activities:• Evidence Presentations• Variation Lab• Birds and Dots Lab• Model-based Inquiry

Introduction to Evolution

Problem• What about the animals that no

one had seen before?

• Churches: “extinction” is blasphemy

• Fossilized creatures didn’t go extinct…they “changed”

Theory of Acquired CharacteristicsJean-Baptiste Lamarck

1. Characteristics that get used, develop. Those that aren’t, get reduced. L'influence des circonstances (adaptive force)

2. Characteristics that develop get passed on to the offspring. Le pouvoir de la vie (complexifying force)

Example (according to Lamarck)

• Giraffes have long necks because their ancestors strained to reach leaves in trees.

• The offspring had slightly longer necks. Over many generations, longer and longer necks developed.

Voyage of the Beagle

90 feet long

Lyell Earth changes over time

DarwinStruggle for existence

Life can changes over time too

MalthusOverpopulation

Plants: well suited to their environments.

Galapagos: different climates, different animals

(Some of) Darwin’s Observations:

Alfred Russel Wallace and Controversy

Theory of Natural SelectionCharles Darwin, Alfred Russel Wallace

1. All organisms vary in their characteristics.2. Organisms always struggle for food, habitat, protection and mates.3. On average, offspring that vary in ways favored by the environment will

survive and reproduce more successfully.4. Over time, favorable characteristics accumulate in the population

Example (according to Darwin and Wallace)

• Giraffes have long necks because their ancestors that had necks slightly longer than average could reach food better than their short-necked relatives.

• These longer-necked giraffes got more food, were healthier, and left more offspring behind.

Darwin/Wallace Lamarck