Factors Affecting Evolution

What are selection pressures?

• The process of choosing which animals to breed in artificial selection

• Changes in allele frequencies due to migration

• Genetic mutations in a population

• Environmental factors that affect the chance of survival of an organism

What is stabilising selection?

• Selection that favors the formation of new species

• Natural selection that keeps allele frequencies relatively constant over generations

• Natural selection that favors extreme phenotypes

• A process that increases genetic diversity

What is an example of directional selection?

• Climate change selecting for smaller body size in fish

• A stable environment where allele frequencies do not change

• Human birth weights being selected for an intermediate range

• A population of plants where all individuals have the same flower color

What is genetic drift?

• A process where environmental selection pressures guide evolution

• A mechanism that increases the mutation rate

• A change in allele frequencies due to chance in a small population

• The movement of alleles from one population to another

What is the bottleneck effect?

• An increase in genetic diversity due to mutation

• A sudden reduction in population size due to environmental events

• A gradual change in allele frequencies over time

• The process of selecting the best individuals for breeding

What is the founder effect?

• The impact of genetic mutations in a new environment

• A phenomenon where a new population starts with a small number of individuals

• The advantage that the original population has over its new offshoots

• The effect of natural selection on founding populations

How does climate change affect fish size according to recent findings?

• It increases genetic diversity in fish populations

• It selects for smaller body size due to increased metabolic needs

• It selects for larger body size due to increased food availability

• It has no significant effect on fish size

What role does genetic drift play in evolution?

• It decreases genetic diversity by favoring certain alleles

• It ensures that advantageous traits are passed on to the next generation

• It increases the effect of natural selection

• It changes allele frequencies by chance, especially in small populations

What can cause a genetic bottleneck?

• Rapid population growth

• A major environmental event that drastically reduces population size

• The removal of selection pressures

• The introduction of a new allele into a population

What is an example of the founder effect?

• A population of lizards with a limited range of scale colors due to their founders

• Fish populations increasing in size due to global warming

• A large population of cheetahs becoming genetically diverse

• A population of plants where all individuals are resistant to a disease