The Evolution of Evolutionary Thought

Question 1

Aristotle and others

Answer 1

• Species are fixed and unchanging
• Earth is relatively young (few thousand years)
• Species could not become extinct

Question 2

Georges Baffon

Answer 2

Church doctrine explained the “hierarchy of man” and age of earth
- noted similarities between organisms
- individuals within species change (are different)
- earth is very old (6,000-10,000 years)

Question 3

James Hutton

Answer 3

• forces that formed earth acting in a gradual uniform way (Uniformitarianism)

Question 4

Thomas Malthus

Answer 4

political economist who wrote a pamphlet with the main points
- over production of the young (more kids than parents, not all kids live to adulthood)
- population increase will outpace resources (people will need to fight over them)
- irresponsibility of the lower classes

Question 5

Georges Cuvier

Answer 5

• older, simpler fossils appeared in lower layers of rock
• fossils represent extinction but then special creations

Question 6

Jean-Baptiste de Lamark

Answer 6

• strong advocate of evolution
• species evolve as a result of interactions with their environment
• proposed a mechanism for evolution - “progeny inherit acquired traits from parents”
  **acquired in lifetime (this is epigenetics so technically true)

Question 7

Charles Lyell

Answer 7

• renewed idea of uniformitarianism (and gradual change)
• thought the earth was old by looking at the fossil record
• believed many plants and animals remained unchanged over time
• became a very strong supporter of Darwin

Question 8

Charles Darwin (1809-1882)

Answer 8

• received a degree in theology (1831)
• embarked on a 5-year trip (1831-1836) as a naturalist aboard the HMS beagle
• when he returned to England began to develop the theory of evolution from…
  (a) observations during the voyage
  (b) the ideas of Hutton Cuvier, Buffon, Lamark, Lyle and Malthus

Question 9

Darwin’s main ideas

Answer 9

1. population includes individuals that vary from inherited traits
2. more individuals are born than survive to reproduce
3. individuals compete with each other for limited resources
4. within a population, the characteristics of some individuals make them more able to survive a particular environmental challenge
5. the mechanism of evolution is natural selection

Question 10

Investigation since Darwin

Answer 10

• earth is over 4.5 billion years old
  (a) used radiometric dating (see where uranium-238 turns to lead)
  (b) meteorites found on earth

Question 11

What are the oldest fossils

Answer 11

• 3.8 BYO bacteria
• Photosynthesis 3.4 BYA
• 410 MYO vascular plant fossils