4/15/24 - Lecture 9: History of Evolutionary Thought

Question 1

Catastrophism

Answer 1

The theory that sudden, short-lived and violent events led to the extinction of many organisms. Species don’t arise, change, or become extinct.

They are “everywhere”, but are removed then come back later

Evidence: geologic markers for eruptions, floods, etc. that change species composition

Question 2

Gradualism

Answer 2

The hypothesis that evolution proceeds chiefly by the accumulation of gradual changes

Evidence: transition fossils

Question 3

Lamarck’s theory of evolution

Answer 3

Physical changes during an organism’s lifetime can be inherited by their offspring

Question 4

Natural selection

Answer 4

Changes in species through time are due to increased survival and reproduction of some individuals over others, based on differences in their traits

Question 5

Darwin’s theory of evolution

Answer 5

Species change over time
New species come from pre-existing species
All species share a common ancestor