Podcast
Questions and Answers
What does natural selection directly act upon?
What does natural selection directly act upon?
Which scenario best explains the process of natural selection?
Which scenario best explains the process of natural selection?
What happens to unfavourable genetic traits in a population over time according to natural selection?
What happens to unfavourable genetic traits in a population over time according to natural selection?
Which of the following describes an example of a favourable trait within the giraffe population?
Which of the following describes an example of a favourable trait within the giraffe population?
Signup and view all the answers
According to Lamarck's theory, how would giraffes have developed long necks?
According to Lamarck's theory, how would giraffes have developed long necks?
Signup and view all the answers
What is gene flow?
What is gene flow?
Signup and view all the answers
What effect does gene flow have within a single population?
What effect does gene flow have within a single population?
Signup and view all the answers
How does gene flow affect speciation across populations?
How does gene flow affect speciation across populations?
Signup and view all the answers
How would the rate of gene flow typically compare in sedentary organisms versus more mobile organisms?
How would the rate of gene flow typically compare in sedentary organisms versus more mobile organisms?
Signup and view all the answers
What is non-random mating?
What is non-random mating?
Signup and view all the answers
How does non-random mating work against natural selection?
How does non-random mating work against natural selection?
Signup and view all the answers
What happens to a gene once it has been selected for by the environment?
What happens to a gene once it has been selected for by the environment?
Signup and view all the answers
What is natural selection described as in the provided content?
What is natural selection described as in the provided content?
Signup and view all the answers
What did Darwin theorize about the finches in the Galapagos Archipelago?
What did Darwin theorize about the finches in the Galapagos Archipelago?
Signup and view all the answers
Which factor selected for the different beak types in Darwin's finches?
Which factor selected for the different beak types in Darwin's finches?
Signup and view all the answers
Which example best illustrates an ecological niche based on the provided content?
Which example best illustrates an ecological niche based on the provided content?
Signup and view all the answers
What role do mutations play in the process observed in Darwin's finches?
What role do mutations play in the process observed in Darwin's finches?
Signup and view all the answers
What role does population size play in genetic drift?
What role does population size play in genetic drift?
Signup and view all the answers
What can overshadow natural selection in small populations?
What can overshadow natural selection in small populations?
Signup and view all the answers
Which of the following is NOT a cause of mutations?
Which of the following is NOT a cause of mutations?
Signup and view all the answers
In the marble analogy, what does the jar represent?
In the marble analogy, what does the jar represent?
Signup and view all the answers
How do favorable mutations affect an organism's likelihood of survival in a population?
How do favorable mutations affect an organism's likelihood of survival in a population?
Signup and view all the answers
What is the ultimate outcome of genetic drift in a small population given enough time?
What is the ultimate outcome of genetic drift in a small population given enough time?
Signup and view all the answers
Most mutations that occur in an organism are:
Most mutations that occur in an organism are:
Signup and view all the answers
During the marble analogy experiment, what does the replacement of each marble represent?
During the marble analogy experiment, what does the replacement of each marble represent?
Signup and view all the answers
What happened to the light-colored peppered moths during the Industrial Revolution?
What happened to the light-colored peppered moths during the Industrial Revolution?
Signup and view all the answers
Why does genetic drift have less impact on larger populations?
Why does genetic drift have less impact on larger populations?
Signup and view all the answers
Which of the following was NOT a consequence of the Industrial Revolution on the peppered moths?
Which of the following was NOT a consequence of the Industrial Revolution on the peppered moths?
Signup and view all the answers
Which scenario described best illustrates genetic drift?
Which scenario described best illustrates genetic drift?
Signup and view all the answers
What role do mutations play in evolutionary change?
What role do mutations play in evolutionary change?
Signup and view all the answers
What happens to the less common genetic outcomes in a population undergoing genetic drift?
What happens to the less common genetic outcomes in a population undergoing genetic drift?
Signup and view all the answers
What happens to an unfavorable mutation in a population?
What happens to an unfavorable mutation in a population?
Signup and view all the answers
Which term describes changes in the genetic material of an organism?
Which term describes changes in the genetic material of an organism?
Signup and view all the answers
Study Notes
Agents of Evolutionary Change
- Five agents of evolutionary change: mutation, genetic drift, gene flow, non-random mating, and natural selection
Mutation
- Changes to the nucleotide sequence in the genetic material of an organism
- Caused by: errors in DNA replication, exposure to UV or radiation, mutagens, and viruses
- Creates variation in gene pools
- Most mutations are minor and do not impact an organism's fitness
- Mutations are the main provider of new traits for natural selection
Example: The Peppered Moth
- Evolution of the peppered moth due to pollution during the Industrial Revolution
- Light-colored moths died off, dark-colored moths flourished due to camouflage
Natural Selection
- Process by which environmentally favorable genetic traits become more common
- Acts on observable characteristics of an organism
- Favourable traits increase in frequency, unfavourable traits decrease
Example: The Giraffe
- Long-necked giraffes survived and reproduced due to favorable genetic traits
- Short-necked giraffes died off, leading to the emergence of long-necked giraffes
Evolution
- Natural selection leads to adaptations and specialization of organisms
- Can result in the emergence of new species over time
Example: The Finches
- Finches on the Galapagos Islands adapted to different food sources
- Different beak shapes emerged due to genetic variations and natural selection
Genetic Drift
- Random variations in which organisms reproduce, leading to changes in the genetic makeup of a population
- Depends on small population size
- Can overshadow natural selection in small populations
Analogy of Genetic Drift
- Randomly selecting marbles from a jar represents genetic drift
- Changes in the population's genetic makeup occur due to chance
Gene Flow
- Movement of genes from one population to another
- Increases genetic variation in a population
- Reduces the occurrence of speciation
Effects of Gene Flow on Evolution
- Introduces or reintroduces genes to a population
- Makes distant populations genetically similar
Non-Random Mating
- Mating that does not occur due to chance, but due to human interference
- Occurs when the possibility of mating is not the same for all possible pairs of individuals
- Works against natural selection
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the five agents of evolutionary change, including mutation, genetic drift, gene flow, non-random mating, and natural selection in this presentation of notes.
