1. EIVIDENCE FROM ANATOMY AND EMBRYOLOGY

2. EIVIDENCE FROM ANATOMY
Deduction: If the hypothesis of evolution is correct then we should see evidence of this in the anatomy.
Test: Study comparative anatomy
Look for trends

3. EIVIDENCE FROM ANATOMY
Aristotle noted:
*Animals with fur also suckle their young
*Animals with red blood also have backbones & similar skeletons.
What is the cause of such patterns?

4. What is the cause of such patterns?
Forelimb of vertebrates

5. The hypothesis of Devine Creation offers no scientific answer.
What is the cause of such patterns?
The hypothesis of Devine Creation
offers no scientific answer.
But the Hypothesis of Evolution does.
The reason for such similarities are
because these animals shared a common
ancestor who had these traits.

6. Birds Mammals Reptiles Amphibians Fish 200 mya 160 mya 325 mya 375 mya

7. Homology=Similar structure from a common ancestor
e.g. The basic structure of the limb evolved before the groups separated.
It evolved in fish!
Limbs from fins
Amphibian Fish

8. Prediction (Deduction):
Not only will we find a basic similarity in limb structure in vertebrates, we should find great similarity in all systems.
Data:
All vertebrates have the same basic organ systems: skeletons, muscles, nerves, circulation, respiration, kidneys, digestive tracts, biochemistry.
And differences among vertebrates show trends that reflect evolutionary shifts.

9. DATA: Trends in organ structure
Evolution of the vertebrate heart
Number of Chambers ½ A V
Fish
Bird & Mammal
Reptile
Amphibian

10. DATA: Trends in organ structure
Respiration
Fish Gills
Amphibian Gills & Simple Lungs
Reptile Complex Lungs
Birds & Mammals Very Complex Lungs
These trends are not expected with Devine Creation
They are expected with the model of
change through time= Evolution

11. This principle of homology allows us to predict that when we discover a new species of vertebrate or fossil that they too will have similar structures derived from a common ancestor.

12. The principle of homology allows us to use animals such as monkeys and rats in testing drugs and use them in experimental procedures as proxies for humans.

13. How can you tell if 2 structures are homologous ?
Answer these questions:
Are the two structures fundamentally similar in their basic structure?
Do the structures have the same embryology?
Does the common ancestor have a similar structure?
If so, the structures are probably homologous even if they are performing different functions

14. REMEMBER
In order for the structures to be homologous the organisms’ common ancestor had to have the structure !
All of the examples in the previous clicker question have classically been considered analogous.
They perform similar functions but evolved independently

15. ANALOGY=Similar function of two structures independently evolved i. e
ANALOGY=Similar function of two structures independently evolved i.e. not from a common ancestor
Bird
Bat
Analogous
Structures
Homoplasies
Fly

16. Homology in Leaf Structure

17. Vestigial Structures= Structures with no apparent function or reduced function
e.g. Human
Goose bumps when you are cold
Tail bone--coccyx
Muscles to move the ears & scalp
Snakes’ lung
Cave animals’ blind eyes
Wings of flightless birds

18. Vestigial Structures= Structures with no apparent function or reduced function
Why would a creator have formed a structure without function?
How can we understand the Creator’s logic?
There is a function but you just haven’t found it yet.

19. The Evolutionary model provides an answer for vestigial structures.
These structures did have a function in an ancestor, but change in the life style led to the gradual disappearance.
*There is a disadvantage to keeping the structure
it “gets in the way”
and costs energy to maintain.

20. EIVIDENCE FROM EMBRYOLOGY
Deduction: If the hypothesis of evolution is correct then we should see evidence of this in the embryology.
Test: Examine the development of embryos
Look for trends
Aristotle

21. Evidence from Embryology
Von Baer (1866)
The development of all vertebrate embryos is similar
Law of Development
General traits will evolve first
Specific traits will evolve later

22. Vertebrate Embryos

24. Haeckel’s Principle of Recapitulation “Biogenetic Law”
“Ontogeny Recapitulates Phylogeny”
Ontogeny= Individual development of embryo
Recapitulates= Repeats
Phylogeny= Evolutionary History
The individual development of the individual repeats the sequence of events that occurred during evolution So

25. Whale Examples
Whale nostrils
Whale teeth
Whale hair

26. Human examples
Gill Pouches
Tail

27. Creation Model does not scientifically address these problems.
Evolution Model provides a satisfactory explanation.
These patterns are vestiges of development that once were functional. The genes are still present.

28. "Descent With Modification"
Evaluation
The data from anatomy & embryology
support the hypothesis of evolution
"Descent With Modification"