Chapter 17 Studyguide

Specification of Galapagos finches

What occurred because there was a founding of a new population, geographic isolation, changes in the new population's gene pool, behavioral isolation, and ecological competition?

True

True or False: Evolutionary adaptations increase an individual's ability to pass along its alleles.

True

True or False: The Grants' data showed that natural selection takes place frequently and sometimes rapidly.

Maintains genetic equilibrium

A population that satisfies few conditions of the Hardy-Weinberg principle do what?

Speciation on

Among the finch populations of the Galápagos Islands, the founder effect, reproductive isolation, and competition all contributed to what?

temporal isolation

Form of reproductive isolation in which two populations reproduce at different times

Speciation

Formation of new species

Gene shuffling

How does genetic recombination result in genetic variation?

Changes in allele frequencies and to changes in phenotype frequencies

How does natural selection affect a single-gene trait?

Alleles in the gene pool of a population

In genetic terms, evolution is defined as any changes in the relative frequency of what?

Any change in relative frequency of alleles in a population

In genetic terms, what indicates evolution is occurring in a population?

Less

Is there less or more change of genetic drift in larger populations than in smaller populations?

Genetic variation

Mutation, lateral gene transfer, and genetic production during sexual reproduction are all sources of what?

Polygenic traits

Natural selection on what can affect the relative fitness of phenotypes and thereby produce one of three types of selection: directional selection, stabilizing selection, or disruptive selection?

Single-gene traits

Natural selection on what can lead to changes in allele frequencies and, thus, to changes in phenotype frequencies?

Frequently and sometimes rapidly

The Grants' data showed that natural selection takes place what and what?

Phenotypes

The number of What produced for a trait depends on how many genes control the trait?

lateral gene transfer

The transformation of genes between individual cells is called what?

reproductive isolation

This can develop in a variety of ways, including behavioral isolation, geographic isolation, and temporal isolation.

The five conditions that can cause evolution and disturb genetic equilibrium

What are nonrandom mating, small population size, immigration or emigration, mutation, or natural selection do?

Evolutionary adaptations

What increases an individual's ability to pass along its alleles?

Founder effect

What is a change in allele frequencies as a result of the migration of a small subgroup of a population?

Bottleneck effect

What is a change in allele frequency following a dramatic reduction in the size of a population?

Directional selection

What is a form of natural selection in which individuals atone end of a distribution curve have higher fitness than individuals in the Middle or the other end of the curve?

Stabilizing selection

What is a form of natural selection in which individuals near the center of a distribution curve have higher fitness than individuals at either end of the curve?

Genetic drift

What is a random change in allele frequencies caused by a series of chance occurrences that cause an allele to become more or less common in a population called?

Genetic equilibrium

What is a situation in which allele frequencies in a population remain the same?

Single gene trait

What is a trait controlled by one gene that has two alleles?

polygenic trait

What is a trait controlled by two or more genes?

Mutation

What is any change in the genetic material of a cell?

Sexual selection

What is it called when individuals select mates based on heritable traits?

Disruptive selection

What is natural selection in which individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle of the curve?

Genetic drift

What is random change in allele frequency caused by a series of chance occurrences that cause an allele to become more or less common in a population?

Allele Frequency

What is the number of times that an allele occurs in a gene pool compared with the number of alleles in that pool for the same gene called?

Relative frequency of an allele

What is the proportion of that allele with respect to all of the alleles for that particular gene in the genomes of all the members of a species or in a selected population?

Hardy-Weinberg Principle

What predicts that five conditions can disturb genetic equilibrium and cause evolution to occur?

Population

What refers to a group of individuals of the Sam species that mate and produce offspring?

Species

What refers to a group of individuals that mate and produce offspring?

Isolation

When two populations become reproductively what, they can evolve into two separate species.

Behavioral isolation

When two populations within a species develop differences in courtship rituals, they may no longer interbreed due to what?

Hardy-Weinberg Principle

Which principle states that allele frequencies in a population remain constant unless one or more factors cause those frequencies to change?

asexual reproduction

Which type of reproduction creates an identical offspring?

sexual reproduction

Which type of reproduction results in different offspring from the parent?

disruptive selection

Which type of selection is most likely to create two distinct phenotypes at opposite extremes?

Combining alleles

Why does sexual reproduction provide more opportunities for genetic variation than asexual reproduction?

allele frequency

how often an allele occurs in a gene pool relative to the other alleles for that gene

behavioral isolation

isolation between populations due to differences in courtship or mating behavior

temporal isolation

A field contains similar wild flower species that bloom at different times. The flower species are separated by what?

Gene pool

Combined genetic information of all the members of a particular population

geographic isolation

the physical separation of populations due to geographic barriers that prevent interbreeding