1. The Father of Evolution
Charles Darwin
The Father of Evolution

2. Charles Darwin Born in 1809, Shrewsbury, England Naturalist
Studied Medicine
Degree in Theology
Buried in Westminster Abbey

3. Darwin sailed aboard the Beagle for 5 years, working as a naturalist.
After Cambridge, Charles was recommended for a surveying trip on the HMS Beagle.
The mission of the voyage was to chart stretches of the South American coast.
Darwin sailed aboard the Beagle for 5 years, working as a naturalist.

4. Row, row, row your boat! Voyage of H.M.S. Beagle 5 year unpaid voyage
Darwin studied plants, animals, collected fossils
Found fossils of extinct animals that were similar to modern species. On the Galapagos Islands in the Pacific Ocean he noticed many variations among plants and animals of the same general type as those in South America.

5. This voyage lasted from 1831 to 1836.

6. Many of Darwin’s conclusions were based on observations of wildlife in the Galapagos Islands.
The Galapagos Islands lie 500 miles west of Ecuador in the Pacific Ocean, directly on the equator.
“Galapagos” means turtle.

7. Darwin was influenced by :
Geologist
Contribution:
Earth is very old (much older than thought)
Earth has changed over time (constantly changing)
Sir Charles Lyell

8. Another influential person
Economist
Contribution:
Populations have the potential to increase faster than the available food supply
Thomas Malthus

9. Another influential scientist
Alfred Russel Wallace
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Another influential scientist
Botanist
Contribution:
Essay described evolution by natural selection
Alfred Russel Wallace
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10. Darwin noticed there were several types of finches on these islands.
Galapagos finches
Darwin noticed there were several types of finches on these islands.
In particular, Darwin observed something odd about the finches: they all looked like a bird he had seen on the South American continent.

11. In all, there were 13 types of finches, some species being confined to only one island.

12. The most distinct difference among finch species is their beaks, which are adapted for the specific diets available on the islands.

13. Darwin wondered if the birds and other animals had been created to match their environment, why didn’t these birds look like the birds of the African continent, since the environments of both the Galapagos and Africa were similar.

14. Once on the islands, the birds must have changed over the years.
Darwin guessed that some of the birds from South America migrated to the Galapagos.
Once on the islands, the birds must have changed over the years.

15. This would explain the numerous species of birds present.
large ground finch
woodpecker finch
cactus finch
This would explain the numerous species of birds present.

16. This tree has how many major branches?
Warbler Finch
Tree Finch
Ground Finch
Certhidea olivacea
& C. Fusca
Geospiza difficilis
G. conirostris
G. scandens
Cacts Finch
(nectar,eeds, blood)
G. magnirostris
Seed-eating Finch
G. fuliginosa
G. fortis
Platyspiza crassitrostris
C. heliobates
Cactospiza pallida
Woodpecker-like Finch
Vegetarian Finch
Insect-eating Finch
Camarhynchus pauper
C. psittacula
C. pauper
(seeds & insects)
PHYLOGENIC TREE:
A diagram showing the evolutionary history of a species of an animal.
This tree has how many major branches?

17. TWO TYPES OF EVOLUTION:
Convergent Evolution: process by which unrelated species become similar as they adapt to similar environments.
Divergent Evolution: formation of new species from an existing species adapting to new environments.
What type of evolution is a phylogenic tree?

18. After returning from the Galapagos and studying all the different types of plants & animals. Darwin concluded new concepts of change….

19. evolution Natural Selection Darwin called this…
which means (change in species over time)
Darwin extended these principles to biology, which helped him form his theory of…
Natural Selection
…or Survival of the Fittest.

20. Five basic components of
Natural Selection

21. 1. All species have genetic variation.
Every species is different, even within itself.
Look around you…are you all the same?

22. 2. The environment presents challenges to survival.
There is a constant struggle for survival. Examples are:
Drought
Fires
Floods
Snowstorms
Hurricanes
Tornadoes
Other natural disasters

23. 3. Organisms produce more offspring than can survive
3. Organisms produce more offspring than can survive. Competition exists WITHIN and AMONG species.
Within a Species
Among a Species
food
food
space
space
mates

24. Darwin’s definition of fitness:
4. Individuals that are fit to their environment leave more offspring than those who aren’t.
Darwin’s definition of fitness:
an organism which has successfully adapted to its environment
Organisms who possess favorable traits will leave more offspring.
In other words, he who spreads the most genes wins!
1st

25. 5. Characteristics of fit individuals increase in a population over time.
Over time, genes for less favored characteristics will be eliminated from the gene pool.
Example: giraffes and their long necks.

26. Therefore Darwin’s contributions:
Provided evidence that species evolve
In 1859, he proposed the Theory of Natural Selection to explain evolution (Survival of the fittest)
Over time, change within species leads to the replacement of old species by new species as less successful species become extinct.
Some evidence from fossils may prove that species on Earth have evolved from ancestral forms that are extinct. (species that have disappeared permanently.)

27. What is a species?
One or more populations of individuals that can interbreed, producing fertile offspring.
Speciation is the process by which new species are formed over time.

28. Equus, the modern horse, evolved from the dog-sized Hyracotherium
Equus, the modern horse, evolved from the dog-sized Hyracotherium. Notice it evolved from a four-toed front foot to the one-toed front foot of the modern horse.

29. Scientific Evidence of Evolution includes:
Fossil Record
Comparative Anatomy
Embryology
DNA & Proteins (Biochemical Evidence)

30. Fossil Record In order for fossils to form: Calcium must be replaced
Burial must occur by sediment
Usually occurs in swamps, mud, ocean floors, tar pits, etc.

31. COMPARATIVE ANATOMY:
Homologous structures are characteristics which are shared by related species because they have been inherited in some way from a common ancestor. .
Turtle
Alligator
Bird
Mammal
For example, the bones on the front fins of a whale are homologous to the bones in a human arm and both are homologous to the bones in a chimpanzee arm.

32. Analogous Structures
similar in function but not in origin and structure
In convergent evolution, organisms evolve similar features independently, often because they live in similar habitats.

33. VESTIGIAL STRUCTURES: structures that serve no useful purpose
organs so reduced in size that they are nonfunctioning remnants of similar organs in other species
ex: human tailbone, appendix, whale pelvis

34. EMBRYOLOGY
Embryos of different species may appear similar in early stages of development
Embryo drawings by cbray
ex: vertebrate development

35. 3 COMPARATIVE ANATOMY Comparison of similarities in embryos can show:
Embryo drawings by cbray
Relationship to a common ancestor