Question 1

Data on survival of juvenile black-bellied seedcrackers as a function of beak size is shown in the accompanying figure.Given the relative survival rates of juvenile birds in terms of both the lower mandible width and length,this is a clear example of ________.

Accepted Answer

A)   directional selection
B)   stabilizing selection
C)   disruptive selection
D)   selection gradient C

Question 2

Multiple trait analysis (beak width and beak depth)on the medium ground finch,in response to the drought of 1976-77,has generated the three-dimensional graph,shown in the accompanying figure.If the blue triangles represent fitness levels for the quantified parameters,then the birds showing the greatest fitness should have ________.

Accepted Answer

A)   deep, wide beaks
B)   deep, narrow beaks
C)   shallow, wide beaks
D)   shallow, narrow beaks B

Question 3

Continuously variable traits typically have a(n)________,[two words] otherwise known as a "bell-curve."

Accepted Answer

normal distribution

Question 4

The fraction known as the broad-sense heritability (where VG = genetic variation,VP = phenotypic variation,and VE = environmental variation)is expressed by ________.

Accepted Answer

A)   VG/VP
B)   VG/VG + VE
C)   VG/VP + VE
D)   VG/VE
E)   A and B are both accurate.

Question 5

Variation among individuals that is due to variation in factors other than environmental influences is called ________.

Accepted Answer

A)   phenotypic variation
B)   genetic variation
C)   broad-sense heritability
D)   narrow-sense heritability

Question 6

________ selection and ________ selection tend to reduce the amount of variation in a population,whereas ________ selection tends to increase the amount of variation in a population.

Accepted Answer

The answer of ________ selection and ________ selection tend to...

Question 7

In populations where individuals with extreme values of a trait have the highest fitness,the average value of the trait may not change,but the amount of variance in the trait does increase over time.This set of circumstances is known as ________.[two words]

Accepted Answer

The answer of In populations where individuals with extreme values...

Question 8

The total variation in a trait is known as the ________.

Accepted Answer

A)   phenotypic variation
B)   genetic variation
C)   environmental variation
D)   broad-sense heritability
E)   narrow-sense heritability

Question 9

Some have proposed that where human IQ scores are concerned,heritability can tell us something about the causes of differences between population means such as ethnic groups.Explain why this perspective is erroneous.

Accepted Answer

The answer of Some have proposed that where human IQ...

Question 10

Traits that are conditioned by one locus are most appropriately termed ________.

Accepted Answer

A)   qualitative traits
B)   quantitative traits
C)   continuously variable traits
D)   environmentally conditioned traits

Question 11

________ refers to the fraction of the total variation in a trait that is due to variation in genes.

Accepted Answer

The answer of ________ refers to the fraction of the...

Question 12

Determining the slope of the best-fit line for a data set of midparent versus midoffspring values by utilizing least-squares linear regression generates an estimate of heritability known as the ________.

Accepted Answer

A)   phenotypic variation
B)   environmental variation
C)   broad-sense heritability
D)   narrow-sense heritability

Question 13

When Bradshaw and colleagues investigated the quantitative trait loci (QTL)of two species of Mimulus (Mimulus cardinalis and Mimulus lewisii),they used marker loci as a way to map the QTLs.Their results are shown in the accompanying figure.According to these results,________.

Accepted Answer

A)   the differences in genotype for the majority of these QTLs explained small amounts of the variations in flower phenotypes for both species
B)   some of the QTLs did have pronounced effects on the flowers' phenotypes
C)   at least one QTL explained 90% of the phenotypic variance for each species
D)   All of the above.

Question 14

Compare and contrast qualitative traits/genetics with quantitative traits/genetics.

Accepted Answer

The answer of Compare and contrast qualitative traits/genetics with quantitative...

Question 15

In populations where individuals with intermediate values of a trait have the highest fitness,the average value of the trait does not change over time,but the variation tends to be reduced.This set of circumstances is known as ________.[two words]

Accepted Answer

The answer of In populations where individuals with intermediate values...

Question 16

It becomes possible to predict evolutionary changes in a population after we have measured two attributes affecting the population in question.What two measures allow us to make such predictions?

Accepted Answer

The answer of It becomes possible to predict evolutionary changes...

Question 17

Variation among individuals that is due to factors other than genetic factors is called ________.

Accepted Answer

A)   phenotypic variation
B)   environmental variation
C)   broad-sense heritability
D)   narrow-sense heritability

Question 18

In cases where selection consistently favors a higher (or lower)value of a trait or phenotype,the result over time is a change in the average value of a trait in the population.This mode of selection is known as ________.

Accepted Answer

A)   directional selection
B)   stabilizing selection
C)   disruptive selection
D)   selection gradient

Question 19

The abbreviation QTL stands for ________,[three words] which are those genes that influence nonqualitative traits.

Accepted Answer

The answer of The abbreviation QTL stands for ________,[three words]...

Question 20

To learn the location of and determine the role that QTLs have on phenotypes,researchers look for associations between a marker locus genotype and phenotype.Examples of research focusing on such methods have been conducted on ________.

Accepted Answer

A)   human personality traits
B)   human diseases such as Crohn's disease
C)   the speed of thoroughbred race horses
D)   All of the above.

Exam 9: Evolution at Multiple Loci: Quantitative Genetics