Evolution

Question 2

Define evolution as it relates to evolutionary theory

Answer 2

Change in the heritable characteristics of biological populations over successive generations.

Evolution explains how species adapt and develop over time.

Question 3

Define natural selection

Answer 3

Process by which organisms better adapted to their environment tend to survive and produce more offspring.

It is a mechanism of evolution proposed by Charles Darwin.

Question 4

Define artificial selection

Answer 4

Process by which humans breed selected organisms for specific traits.

Examples include dog breeding and crop cultivation.

Question 5

Define adaptation

Answer 5

A trait that helps an organism survive and reproduce in its environment.

Adaptations can be structural, behavioral, or physiological.

Question 6

Define species

Answer 6

A group of organisms that can interbreed and produce fertile offspring.

Species are often defined by their genetic similarity and reproductive isolation.

Question 7

Define population in the context of evolutionary theory

Answer 7

A group of individuals of the same species living in a specific area.

Populations are the units of evolution.

Question 8

Summarize Darwin’s contributions to evolutionary theory

Answer 8

Proposed the theory of natural selection as a mechanism for evolution.

His work was foundational in understanding species adaptation.

Question 9

Summarize Lyell’s contributions to evolutionary theory

Answer 9

Promoted the idea of uniformitarianism, which suggests that the Earth’s features are the result of long-term processes.

This concept influenced Darwin’s thinking about gradual evolution.

Question 10

Summarize Lamarck’s contributions to evolutionary theory

Answer 10

Proposed the theory of inheritance of acquired characteristics.

This theory was later disproven but was an early attempt to explain evolution.

Question 11

Summarize Wallace’s contributions to evolutionary theory

Answer 11

Independently developed the theory of natural selection and contributed to the idea of biogeography.

He is often credited with prompting Darwin to publish his findings.

Question 12

Contrast Lamarck’s theory of inheritance of acquired characteristics with Darwin’s theory of natural selection using giraffes

Answer 12

Lamarck: Giraffes stretch their necks to reach higher leaves, and this trait is passed on. Darwin: Giraffes with longer necks survive better and reproduce more.

This highlights the difference between acquired traits and inherited traits.

Question 13

Explain how evolution in organisms is a function of populations rather than individuals

Answer 13

Evolution occurs through changes in allele frequencies within populations over time.

Individual organisms do not evolve; populations do.

Question 14

Explain the importance of variation in the process of natural selection

Answer 14

Variation provides the raw material for natural selection to act upon, allowing for adaptation to changing environments.

Without variation, all individuals would have the same traits and adaptability would be limited.

Question 15

How do new species arise?

Answer 15

New species arise through processes such as speciation, which can occur via geographic isolation or reproductive barriers.

An example includes the anole lizards in the provided resource.

Question 16

List forms of evidence for evolution

Answer 16

• Fossil records
• Vestigial structures
• Homologous structures
• Analogous structures
• Embryology
• Molecular evidence

These forms of evidence support the theory of evolution.

Question 17

State factors contributing to microevolution

Answer 17

• Mutation
• Gene flow
• Genetic drift
• Bottlenecks
• Founder effect
• Non-random mating
• Natural selection

These factors can lead to changes in allele frequencies within a population.

Question 18

What are the conditions required for populations to be at Hardy-Weinberg equilibrium?

Answer 18

No mutations, random mating, no natural selection, large population size, and no gene flow.

Hardy-Weinberg equilibrium is a theoretical state where allele frequencies remain constant.

Question 19

Define and compare artificial selection, natural selection, and sexual selection

Answer 19

• Artificial selection: Human-driven breeding for desired traits.
• Natural selection: Survival and reproduction based on advantageous traits.
• Sexual selection: Preference for certain traits in mate selection.

Examples include dog breeding (artificial), predator-prey interactions (natural), and peacock tail feathers (sexual).

Question 20

What is speciation?

Answer 20

The process by which new species arise due to evolutionary changes.

It can occur through mechanisms such as allopatric and sympatric speciation.

Question 21

Differentiate between transformative and divergent speciation

Answer 21

Transformative: One species evolves into another. Divergent: Two or more species evolve from a common ancestor.

These processes illustrate different paths of evolutionary change.

Question 22

Differentiate between allopatric and sympatric speciation

Answer 22

• Allopatric: Speciation due to geographic isolation.
• Sympatric: Speciation occurring within the same geographic area.

Both processes lead to reproductive isolation.

Question 23

What are reproductive barriers?

Answer 23

Factors that prevent species from interbreeding, leading to speciation.

These can be prezygotic or postzygotic barriers.

Question 24

Compare convergent and divergent evolution

Answer 24

• Convergent evolution: Unrelated species develop similar traits due to similar environments.
• Divergent evolution: Related species evolve different traits due to different environments.

These concepts illustrate how species adapt to their ecological niches.

Question 25

What is sexual dimorphism?

Answer 25

The differences in appearance between male and female members of the same species. ## Footnote Males may be at a disadvantage due to increased visibility to predators.

Question 26

Identify different types of selection

Answer 26

* Disruptive selection * Directional selection * Stabilizing selection ## Footnote Each type of selection affects population traits in different ways.

Question 27

What is co-evolution?

Answer 27

The process where two or more species influence each other's evolution. ## Footnote An example is the relationship between pollinators and flowering plants.

Question 28

Define mutualism

Answer 28

A symbiotic relationship where both species benefit. ## Footnote An example is bees pollinating flowers while obtaining nectar.

Question 29

Define mimicry

Answer 29

An adaptation where one species evolves to resemble another for protection or advantage. ## Footnote An example is the viceroy butterfly mimicking the toxic monarch butterfly.