People who made scientific contributions to evolution

Question 1

George LeClerc

Answer 1

LeClerc (1707-1788):
First person to challenge idea that life forms are unchanging
Noted similarities between humans and apes and speculated they must have a common ancestor
Suggested earth was more than 6000 years old (which was common belief)
…In 1830’s studies began in areas of Paleontology, geology, geography, biology

Question 2

Mary Anning

Answer 2

• Skilled at collection fossils
• Contributed to the field of paleontology
• Found the first plesiosaur, and aquatic reptile

Question 3

Georges Cuvier

Answer 3

Cuvier (1769 – 1832):
- Credited with developing science of paleontology
Paleontology: study of ancient life through fossils
- Cuvier found each layer of rock (stratum)had a different group of fossils /species
- The deeper the layer, the less alike they were to modern life
- Found new species appeared as other disappeared
This proved that species can become extinct
- Because Cuvier believed that species remain unchanged overtime he explained his finding with the theory of Catastrophism
Catastrophism: Earth experienced many destructive catastrophic events (floods, droughts, volcanic
eruptions, etc.) which caused the extinction of species that were then replaced by new species form a
region nearby (refer to Figure 8.2 p.327)

Question 4

Charles Lyell

Answer 4

Lyell (1830):
- Rejected catastrophism along with Hutton
- By examining fossil deposits, stated the Earth’s surface has undergone and continues to undergo slow,steady, gradual changes.
Proposed idea of uniformitarianism
Uniformitarianism: geological changes are slow and continuous (not catastrophic) and that slow subtle changes can result in substantial change
…So together Hutton & Lyell showed that the Earth must be unimaginably ancient and that dramatic change could result over such extremes of time through slow, slight processes.

Question 5

Jean-Baptiste Lamarck

Answer 5

Lamarck (1744-1829):
- Noticed that animals changed to fit their environment, like moles becoming blind or birds losing teeth.
- He thought these changes were passed on to offspring, like a giraffe’s long neck if its parents stretched for food.
- This idea is called the inheritance of acquired traits.

Question 6

Charles Darwin

Answer 6

Darwin (1809 – 1882):
- set sail on the HMS Beagle
- he developed the theory of evolution by Natural selection
Theory Of Evolution By Natural selection: Theory explaining how life has changed and continues to change during Earth’s history
Evolution: the process of genetic change in a population over time
- populations change over time and individuals with traits that help them survive are more likely to survive
- This is called the Survival of the Fittest
Survival of the fittest: organisms compete for limited resources. Organisms with favourable traits that helping them survive will have an increased chance of reproduction. If they reproduce, a growing number of the population will have these traits in later generations
- Darwin calls this Natural Selection
- It is important to note that Darwin did not use the word Evolution he used Descent with Modification
Descent with Modification: theory that natural selection does not demonstrate progress but results in the ability to survive local environmental conditions