Evolution: Principles Of Natural Selection

Question 1

What is evolution?

Answer 1

Evolution is the process of biological change in populations over time that makes descendants different from their ancestors.

Question 2

What are the two types of evolution?

Answer 2

The two types of evolution are microevolution and macroevolution. Microevolution affects smaller populations, while macroevolution affects multiple populations.

Question 3

Who developed the theory of natural selection?

Answer 3

The theory of natural selection was developed by Charles Darwin.

Question 4

What is natural selection?

Answer 4

Natural selection is the process in which organisms with the “best” traits (adaptations) will live longer and reproduce more than others, causing changes in the population over time.

Question 5

What is the meaning of “fitness” in natural selection?

Answer 5

“Fitness” is a measure of how well an organism can survive in its environment.

Question 6

What are the four principles of natural selection?

Answer 6

The four principles of natural selection are overproduction of offspring, variation, adaptation, and descent with modification.

Question 7

What is adaptation?

Answer 7

Adaptation is a feature that allows an organism to survive in its environment.
Beneficial traits become more common over time
Organisms that live longer and reproduce more cause changes to the gene pool
The gene pool is the combined alleles of all individuals in the population

Question 8

What is directional selection?

Answer 8

Directional selection is a type of natural selection in which individuals with extreme versions of a trait survive better and reproduce more than others.

Question 9

What is disruptive selection?

Answer 9

Disruptive selection is a type of natural selection in which the population is split into two groups with extreme traits, favoring the two extremes over the intermediate group.

Question 10

What is stabilizing selection?

Answer 10

Stabilizing selection is a type of natural selection that eliminates extreme expressions of traits when the average expression leads to higher survival rates. Extremes are not beneficial.

Question 11

What are the Five Fingers of Evolution?

Answer 11

The Five Fingers of Evolution are mutations, natural selection, genetic drift, gene flow, and non-random mating (sexual selection).

Question 12

What is genetic drift?

Answer 12

Genetic drift is a random change in the frequency of alleles in a population over time.

Question 13

What is the Founder Effect?

Answer 13

The Founder Effect is a loss of genetic diversity when a new population is founded by a small group of colonizers.
ex.) polydactyly in the Amish population

Question 14

What is the Bottleneck Effect?

Answer 14

The Bottleneck Effect is when an environmental event results in only a few individuals surviving, resulting in a loss of genetic variation in the population.

Question 15

What is gene flow?

Answer 15

Gene flow is the movement of genes in and out of a population during migration, resulting in increased genetic variation.

Question 16

What is non-random mating (sexual selection)?

Answer 16

Non-random mating, also known as sexual selection, is the selection of traits that are not necessarily good for survival fitness but are necessary for reproduction. It disrupts the frequencies of alleles in the gene pool.

Question 17

Who is Charles Darwin?

Answer 17

An English naturalist who went on a trip to the Galapagos Islands and observed finches and tortoises that had specific traits for the island they inhabited.

Question 18

What is the effect of rare alleles decreasing in frequency in a population and why is it more apparent in smaller populations?

Answer 18

The effect of rare alleles decreasing in frequency in a population is a loss of genetic variation, while other alleles increase in frequency. This effect is more apparent in smaller populations because populations shrink.

Question 19

What was believed before?

Answer 19

Inheritance of acquired traits (Lamarck)
Species evolve based on use/disuse of and inheritance of acquired traits
Species tend to evolve towards “perfection”