Questions and Answers
Which of the following are mechanisms of evolution? (Select all that apply)
What is the term for the differential reproductive and survival of genotypes?
Natural selection
What is defined as individual males or females having a slight advantage over others and transmitting that advantage to their offspring?
Sexual selection
What is the net movement of alleles in or out of a population called?
Signup and view all the answers
What term describes the changes in gene frequency in a population due to random chance, particularly in small populations?
Signup and view all the answers
Who conducted an experiment with E.coli to test natural selection and what year was it?
Signup and view all the answers
What methods were used by Richard Lenski in his E.coli experiments?
Signup and view all the answers
What were the results of Lenski's E.coli study?
Signup and view all the answers
What is the significance of Lenski's findings regarding E.coli?
Signup and view all the answers
Who performed a study on E.coli consuming glycerol and what were their methods?
Signup and view all the answers
What were the results of Paulsson's experiments?
Signup and view all the answers
What does epistasis refer to?
Signup and view all the answers
What is the competitive exclusion principle?
Signup and view all the answers
Who conducted the 29-year study of two finch species on Daphne Island?
Signup and view all the answers
What were the results of the Grant study on finches?
Signup and view all the answers
What was the significance of the Grant study?
Signup and view all the answers
What does heritability refer to?
Signup and view all the answers
What is the importance of field studies on mechanisms of evolution?
Signup and view all the answers
What type of evolution results from competition and geographic variation?
Signup and view all the answers
What is the relationship of species living in different geographic zones called?
Signup and view all the answers
How is the relationship of species sharing a geographic area defined?
Signup and view all the answers
What is stabilizing selection?
Signup and view all the answers
What is directional selection?
Signup and view all the answers
What does disruptive selection entail?
Signup and view all the answers
Match the following types of selection with their definitions:
Signup and view all the answers
What are the forms of sexual selection?
Signup and view all the answers
What is an example of sexual selection in dung beetles?
Signup and view all the answers
What do dunnocks do to prevent monopolization by one male?
Signup and view all the answers
Study Notes
Mechanisms of Evolution
- Natural selection enhances survival and reproduction of advantageous genotypes.
- Sexual selection allows individuals with traits favored by mates to pass those traits to their offspring.
- Mutation introduces new genetic variations in a population.
- Gene flow refers to the movement of alleles between populations, influencing genetic diversity.
- Genetic drift leads to changes in allele frequencies, especially significant in small populations, and includes the founder effect.
Richard Lenski's E. coli Experiment
- Conducted in 1988, challenging E. coli with feast and famine cycles to observe evolutionary changes.
- E. coli was placed in 12 flasks at body temperature, alternating between feeding and starvation.
- Results showed increased growth rates and size, with different mutations emerging in each bacterial line.
- Notably, one line developed the ability to metabolize citrate for energy, enhancing survival.
Bernhard Paulsson's Glycerol Study
- Investigated the effects of feeding E. coli glycerol, a non-traditional food source.
- Bacteria demonstrated quicker growth; genome sequencing revealed critical gene mutations.
- Some genes required the presence of other mutations to enhance growth, indicating collaborative gene interactions.
Epistasis
- Describes how the effects of one gene are influenced by one or more other genes, altering overall phenotypic expression.
Competitive Exclusion Principle
- Suggests that new species must exploit unique ecological niches to coexist without direct competition.
Peter and Rosemary Grant's Finch Study
- Conducted a 29-year analysis of finch species on Daphne Island, observing changes in mean body size and beak shape related to environmental conditions.
- Results confirmed that adaptations are heritable and that evolutionary changes can be unpredictable.
Heritability
- Refers to the proportion of variability in a population that results from genetic differences, crucial for understanding evolutionary dynamics.
Importance of Field Studies
- Field studies provide vital insights that bridge microevolutionary changes with broader macroevolutionary patterns.
Types of Evolutionary Relationships
- Character displacement arises from competition and geographical variation between species.
- Allopatric speciation occurs when species are isolated geographically.
- Sympatric speciation involves species living in shared geographic areas.
Types of Natural Selection
- Stabilizing selection favors average phenotypes and preserves characteristics, such as human birth weight.
- Directional selection favors individuals with traits varying in one direction, observed in longhorn cattle horn development.
- Disruptive selection favors extreme traits, as seen in the beak sizes of finch species on Santa Cruz Island.
Forms of Sexual Selection
- Involves male-male competition and female choice influencing mating success.
- Male dung beetles can sneak around competitors, while female dunnocks mate with multiple males, promoting diverse mating outcomes.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers the key mechanisms of evolution, including natural selection, sexual selection, mutation, and more. Use these flashcards to test your knowledge about how these processes shape genetic diversity and species adaptation. Perfect for students studying evolutionary biology or related fields.
