Describe the ideal environment for this species of moth.
How many moths do you see?
The picture above shows black and white moths in 2 different environments (A & B). 1. In each environment, which color is most likely to survive?2. If in environment A there were 20 black and 50 white moths, what would happen to the moth populations if all of a sudden the tree bark turned black like in B?
A B
Mrs. Workman,do you have proof of Evolution?
• 1. DNA homology, Amino Acid homology Looking at the number of base differences
• 2. EmbryologyComparing developing organisms
• 3. Geographic distribution of organisms– Australia
• 4. Fossil record– A piece of organism or imprint left behind.– Fossils show that species have changed over time
• 5. Vestigial structures– Body structures that have shrunken and are not used anymore.
Ancestors had a use for them
• 6. Homologous structures– Structures that share a common ancestry and look/behave similarly.
DNA/Amino Acid Homology
• Human 5’A-T-C-T-T-A-C-G-A-A-T-C-A-T-G-C-C-C-T-A-A-C-T-T-C-G-G-C-A-T-T-A-C-G-C-T-A-G-C-3’
• Whale 5’A-C-C-T-T-A-C-C-A-A-T-C-A-T-T-C-C-C-T-A-A-C-T-T-A-G-G-C-A-T-T-A-C-G-C-T-A-G-C-3’
• Frog 5’A-C-C-A-T-G-C-G-T-G-T-C-A-T-C-C-C-C-G-A-G-C-T-T-C-G-G-T-A-T-T-A-C-G-C-A-A-G-C-3’
• Gorilla 5’A-T-C-T-T-A-C-G-A-A-T-C-A-T-G-C-C-C-T-A-A-C-A-T-C-G-G-C-A-T-T-A-C-G-C-T-A-G-C-3’
(Means the same!)
Embryology
Fossils
Geologic Strata and Carbon Dating
Strata Determining relative age
of a fossil based on its location in rock layers
Carbon-14 Used to date any object
composed of carbon Radioactive carbon
decays over time check amount of C14 left in
sample, enabling you to tell age of object
Defining age of fossils!
• Did you know that whales have feet?– Well, sort of….
Fossils help us determine whale evolution
60 million years ago
50 million years ago
40 million years ago
Yesterday
• Human tail-bone, wisdom teeth, appendix (they have no current purpose)
• Snake pelvis
• Whale feet
Vestigial Structures
Homologous Structures Limb adapted to function
means the same!
• PBS Movie – 5 min