2. Darwin's Big Idea and How it Changed Biology

Question 1

Origin of Species

Answer 1

1. All organisms have descended with modification from common ancestors
2. The process leading to adaptations is natural selection

Question 2

Darwin Developed his ideas from…

Answer 2

William Paley (naturalist theologian)- Argument from design

Question 3

Jean-Baptiste de Lamarck

Answer 3

first person to use the term evolution & first to provide a hypothesis for how evolution happened (The inheritance of acquired characters)

Question 4

Darwin read Lyell’s book “Principles of geology” which had 2 implications

Answer 4

1. The notion of a dynamic rather than static world
2. Biological changes build up gradually, by the same mechanisms today as in the past

Question 5

Darwin Studied___ which disproved his idea that species were fixed beings

Answer 5

Galapagos mockingbirds

Question 6

After reading Population by Malthus, Darwin…

Answer 6

believed that exponential growth of human population leads to competition

Question 7

Transformational Evolution

Answer 7

all individuals of a population in a given environment simultaneously acquire the same structures and adaptations as the result of an inherent progressive tendency which drives them continuously towards greater complexity

Question 8

Variational Evolution

Answer 8

variational properties of an organism are those properties relating to the production of variation among its offspring. (phenotypic plasticity)

Question 9

Weismann

Answer 9

predicted that in sexual reproduction, a form of reproduction involving two parents, in the cells of an offspring, half came from the mother’s germ cell and half came from the father’s germ cell

Question 10

Uniformitarianism

Answer 10

the idea that Earth has always changed in uniform ways and that the present is the key to the past

Question 11

Important elements of Darwin’s Theory

Answer 11

1) Evolution occurs primarily at the level of populations (individuals do not evolve)
2) Variation is not directed by environment (individuals do not induce adaptive variation when needed)
3) Most fit type depends on the environment
4) ‘Survival of the fitter’: Evolution works with available variation, it will not achieve perfection

Question 12

Scientific Theories…

Answer 12

• Are supported by diverse sources of empirical evidence (principles are inferred from observation and experimentation)
• Have testable and falsifiable hypotheses