1. Evidence of Evolution

2. Evolution and the Fossil Record
The horse series is used as evidence of evolution in the fossil record
It shows the evolution of horse from Eohippus to the modern horse.

5. Evolution and the Fossil Record

6. Evidence: Miller-Urey Experiment
Used to demonstrate how life may have began on Earth
Ran an electric current through gases which created amino acids

7. Evidence: Miller-Urey Experiment

8. Evidence: Miller-Urey Experiment
Questions / Issues with the Miller-Urey Experiment
Produced building blocks for life (simplest amino acids) not life itself
Argument is this is too big a leap to make
Are the gases in the experiment the same ones as where present in the early atmosphere?
Geologist since the 70’s have argued that the gases in this experiment were nothing like those of early earth’s atmosphere.

9. Evidence: Darwin’s Finches
Used to demonstrate natural selection as a cause of evolution
Due to selective pressures new species arise to fit niche

10. Evidence: Darwin’s Finches

11. Evidence: Darwin’s Finches
Peter and Rosemary Grant studied finches on the Galapagos in the 70’s and 80’s
When there was a dry year, mostly hard-to-crack seeds remained for finches
Finches with large beaks survived easier
By relating environment to beak size, the Grants showed that natural selection influences evolution

13. Evidence: Darwin’s Finches
Questions / Issues with the Darwin’s Finches
Although the finch species showed evolution, beak sizes returned to the original size after the rains returned (i.e. not net evolution)
Some species of finches appear to be merging through hybridization

14. Evidence: Kettlewell’s Moths
Peppered Moths
Used to demonstrate natural selection
Industrial revolution created soot that killed the lichens growing on trees and changed the background for the moths
Moths were released on different colored bark. Ones that blended in were not eaten by birds
Numbers of black moths surviving were high on dark bark, numbers of white moths were low
When the color of bark changed so did the numbers of white and dark moths

16. Evidence: Kettlewell’s Moths
Questions / Issues about this Kettlewell’s experiment
These moths used in his experiment don’t rest on vertical surfaces.
Did releasing the moths in a concentrated area produce unnatural behavior in the birds?
Does this experiment represent a natural situation.

17. Evidence: Kettlewell’s Moths
Is the change in moth coloration due to bird predation?

18. Evidence: Haeckel’s Drawings
Tries to show evolutionary history in the development of embryos

19. Evidence: Haeckel’s Drawings

20. Evidence: Homologous Structures
Similarity in characteristic resulting from a common ancestor
Forelimbs of mammals are constructed with the same skeletal elements
Similar features are not always from similar DNA
Questions/Issue
Homologous Structures are only considered that if common ancestry is assumed

21. Evidence: Homologous Structures

22. Evidence: Homologous Structures
Vestigial Organs - describes homologous parts of organisms which have lost all or most of their original function in a species through evolution.

23. Evidence: Homologous Structures

24. Summary: Evidence of Evolution
Fossil Record
Suggestive of Evolution
Miller-Urey Experiment
Attempts to demonstrate origin of life
Darwin’s Finches
Demonstrates natural selection and niches
Kettlewell’s Moths
Demonstrates natural selection and fitness
Haeckel’s Drawings
Tries to evolutionary history via embryonic development
Homologous Structures
Draws evolutionary relationship between organisms based on similarities