Transcript Evidence for evolution

Describe the ideal environment for this species of moth.
How many moths do you see?
A
B
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?
Mrs. Workman,
do you have proof of Evolution?
• 1. DNA homology, Amino Acid homology
Looking at the number of base differences
• 2. Embryology
Comparing 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.
(Means the same!)
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-AA-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-AA-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-AG-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-AA-C-A-T-C-G-G-C-A-T-T-A-C-G-C-T-A-G-C-3’
Embryology
Fossils
Defining age of 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
• 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
Vestigial Structures
• Human tail-bone, wisdom teeth, appendix (they
have no current purpose)
• Snake pelvis
• Whale feet
Homologous Structures
means the same!
Limb adapted to function
• PBS Movie – 5 min