Bio 150 Exam 1 - Objectives: Evolution & Natural Selection

Who was James Hutton and what did he contribute to evolutionary theory?

Hutton proposed that Earth is shaped by slow continuous processes over long periods of time.

What did Jean Baptiste Lamarck propose?

Lamarck suggested that organisms change during their lifetimes by using or not using certain body parts and pass those traits to offspring.

What was Charles Lyell’s main idea?

Lyell proposed that the same geological processes shaping Earth today also operated in the past at the same rates.

What is Charles Darwin known for?

Darwin developed the theory of natural selection as a mechanism for evolution.

What did Alfred Russel Wallace contribute to evolutionary theory?

Wallace independently proposed a theory of natural selection similar to Darwin’s which prompted Darwin to publish his work.

How is evolution defined in biology?

Evolution is the genetic change in a population over time.

At what level does evolution occur?

Evolution occurs at the population level not the individual level.

What are the five mechanisms of evolution?

Mutation gene flow genetic drift natural selection and nonrandom mating.

What is genetic drift?

Genetic drift is random change in allele frequencies due to chance events in small populations.

What is natural selection?

Natural selection is the process where individuals with favorable traits survive and reproduce more successfully.

How do genetic drift and natural selection differ?

Genetic drift is random while natural selection is based on differential fitness.

What are the four requirements for natural selection?

Variation in traits heritability differences in fitness and connection between traits and fitness.

What does variation in traits mean?

It means individuals in a population differ in their physical or genetic characteristics.

What does heritability of traits mean?

Heritability means traits are passed from parents to offspring through genes.

What is meant by differences in fitness?

It means some individuals reproduce more successfully than others due to their traits.

What connects heritable traits and variation in fitness?

Traits that improve survival and reproduction become more common over generations.

How is fitness defined in biology?

Fitness is an individual’s ability to survive and reproduce in its environment.

Why is evolution considered a unifying theory of biology?

Because it explains the diversity of life and how organisms adapt to their environments.