1. EVOLUTION IS…
Evolution is a change in a population over time Proposed by Charles Darwin

2. Driven by…
Natural Selection: organisms that are better adapted to their environment will survive, reproduce, and pass down traits

3. Common ancestor (related) Different traits
D I V E R G E N T
Common ancestor (related)
Different traits
Results from SPECIATION and ADAPTIVE RADIATION
Similar structures
Two types

4. DIVERGENT EVOLUTION P A R E N T S P E C I E S T I M E
(C O M M O N A N C E S T O R)

5. DIVERGENT EVOLUTION common ancestor (RELATED)  adapt different traits
Example 1: Dog species descend from a wolf
Example 2: Zebras, Donkeys, and Horses are related

6. Different ancestors (unrelated)
C O N V E R G E N T
Different ancestors (unrelated)
Develop similar traits due to same environment
Different structures that serve the same function
Two types

7. CONVERGENT EVOLUTION P A R E N T P A R E N T S P E C I E S
T I M E
P A R E N T
S P E C I E S
P A R E N T
S P E C I E S

8. CONVERGENT EVOLUTION NOT RELATED  adapted similar traits
Example 1: Bats (mammals), Hawks (birds),
and butterflies (insects)
all have wings
Example 2: Sharks and dolphins have dorsal fins

9. CONVERGENT DIVERGENT DIVERGENT DIVERGENT CONVERGENT CONVERGENT
YOUR WORK
CONVERGENT
DIVERGENT
DIVERGENT
DIVERGENT
CONVERGENT
CONVERGENT

10. EVOLUTION EVIDENCE | Comparative anatomy
Comparing structure and function of body features
Structure = form Function = use
HOMOLOGOUS
Structures
Same structure
Different function
DIVERGENT
ANALOGOUS
Structures
Different structure
Similar function
CONVERGENT
VESTIGIAL
Structures
Serve no
KNOWN purpose

11. HOMOLOGOUS STRUCTURES
Same structure:
Same bones found in
all 4 mammals
Different functions:
Humans use arm to hold
Cat uses leg to claw/climb
Whales use fin to swim
Bat uses wing for flight

12. Different structures:
ANALOGOUS STRUCTURES
Different structures:
Bats are mammals and have bones, butterflies are insects and have an exoskeleton
SAME function:
Use wings for flight

13. VESTIGIAL STRUCTURES APPENDIX & WISDOM TEETH:
Humans today do not need them, but we can assume they were important to our distant ancestors.
WHALE & SNAKE PELVIS:
serve no purpose now, but provide evidence that they evolved from a 4-legged animal

14. YOUR WORK
HOMOLO GOUS
ANALOG OUS
VESTIGIA L

15. EVOLUTION EVIDENCE | DNA & AMINO ACID SEQUENCES
Analyzing molecular data to determine relatedness
More similarities = more closely related
**BEST EVIDENCE FOR EVOLUTION**

16. Cow; more similarities to hippo DNA than the giraffe.
YOUR WORK
Rhesus Monkey
Lamprey
Frog 6 4
Cow; more similarities to hippo DNA than the giraffe.

17. Shows relation between EXTINCT
EVOLUTION EVIDENCE | FOSSIL RECORD
Shows relation between EXTINCT
and LIVING organisms

18. Describe what the fossils tell us about whale evolution
EVOLUTION EVIDENCE
FOSSIL RECORD
50 mya
45 mya
40 mya
36 mya
(most recent)
Describe what the fossils tell us about whale evolution

19. EMBRYO: unborn offspring
EVOLUTION EVIDENCE | EMBRYOLOGY
EMBRYO: unborn offspring
Share a distant common ancestor when organisms look similar during development