Evolution - Gradualism and Punctuated Equilibrium
Who proposed the term "punctuated equilibrium"?
Niles Eldredge and Stephen Jay Gould
What happens in a large population?
Lower evolutionary rate, more likely to appear on the fossil record
Approximately how long does it take for gradualism to occur?
Millions of years
When does punctuated equilibrium occur?
Rapid change occurs when a smaller population of species are isolated from the parent population
Gradualism
Change that is incremental and slow that happens over time
What is an example of gradualistic speciation?
Cichlids
What is speciation?
Creation of a new species
What happens in a small population?
Easier for evolution, higher evolutionary rate
The flaw in gradualism theory is ...
Evidence of gradualism from fossil records are difficult to find due to missing pieces and time gaps
Punctuated Equilibrium
Evolution is slow and it is interrupted by periods of rapid change
What are the two main ways to describe the rate of evolutionary change?
Gradualism and Punctuated Equilibrium
Approximately how long does it take for punctuated equilibrium to occur?
Hundreds of thousands of years