Question 1

In a population, which individuals are most likely to survive and reproduce?
A) the individuals who are best adapted to the environment
B) the largest individuals in the group
C) the individuals who can catch the most prey
D) the individuals who grow the most rapidly

Accepted Answer

Individuals who are best adapted to their environment are more likely to survive and reproduce because they have traits that allow them to better compete for resources and avoid predators. Over time, these advantageous traits become more common in the population through the process of natural selection. The other choices (B, C, and D) may give certain individuals a temporary advantage, but they do not necessarily lead to long-term survival and reproductive success.

Question 2

Which description applies to individuals who are well adapted for a particular environment?
A) They may or may not be equally fit in another environment.
B) They are the best fit for all other environments.
C) They are at a disadvantage in other environments.
D) They will mutate to become fit in other environments.

Accepted Answer

Individuals that are well adapted for a particular environment are better suited for surviving and reproducing in that specific environment, but this does not guarantee their fitness and success in other environments. Adaptations are generally specific to certain environments and can be advantageous only within these environments. Thus, being well adapted in one environment does not necessarily mean that an organism will be equally well adapted in another environment.

Question 3

You notice in the fall that the oak trees on campus change color at slightly different times, even though the environment is the same for all the trees. What is the most likely explanation?
A) Natural selection is causing some trees to change.
B) There are different alleles of the gene responsible for color change.
C) The weather changes the genes of the oak trees each year.
D) All the trees have the same genes, but each tree makes different proteins from the genes.

Accepted Answer

The fact that the oak trees on campus change color at slightly different times suggests that there are different alleles of the gene responsible for color change. This could be due to genetic differences among the trees or to environmental differences that affect the expression of those genes.

Question 4

A population of caterpillars feeds on the leaves of trees in a forest and is in turn food for birds that eat them off the tree leaves. Given this information, which adaptation would be most likely to evolve?
A) Caterpillars would evolve to a larger size.
B) Caterpillars would evolve to eat the bark as well as the leaves.
C) Birds would evolve to eat more types of insects.
D) Caterpillars would evolve to a color that matched the leaves they eat.

Accepted Answer

Caterpillars evolving to a color that matched the leaves they eat would make them harder for birds to see and make it more difficult for the birds to catch them. This adaptation would increase the caterpillars' chances of survival and reproduction, leading to a higher frequency of the trait in the population over time. The other options are not as likely to evolve in response to the given scenario.

Question 5

True or false: The goal of natural selection is to make extreme traits more common.

Accepted Answer

The goal of natural selection is not to make extreme traits more common, but rather to favor traits that provide an advantage for survival and reproduction in a particular environment. This can result in a shift in the proportions of certain traits within a population, but not necessarily towards extreme traits.

Question 6

As natural selection acts on a trait in a population, how will the amount of variation associated with that trait in the population change?
A) Variation will decrease.
B) Variation will increase.
C) Variation will remain the same.
D) Variation will disappear altogether.

Accepted Answer

Natural selection acts on traits that increase an organism's chance of survival and reproduction, which results in individuals with advantageous traits passing on their genes to future generations. This decreases the amount of variation in the population because the advantageous trait becomes more common and the less advantageous traits are selected against. Over time, this can lead to the fixation of a particular trait in the population, reducing the overall amount of variation.

Question 7

What is an allele?
A) a gene that has been changed by natural selection
B) a trait that has been influence by artificial selection
C) a gene that hasn't changed over time
D) a particular version of a gene

Accepted Answer

An allele is a particular version of a gene that varies in DNA sequence and can lead to different traits or phenotypes. It is one of the possible forms of a gene that exists at a specific locus or location on a chromosome.

Question 8

The blueberries found in a typical grocery store have several gene differences compared to wild blueberries. What has caused this difference?
A) natural selection
B) artificial selection
C) a change in the environment
D) genetic engineering

Accepted Answer

The difference in the genes between the blueberries found in a grocery store and wild blueberries is likely due to artificial selection. Growers selectively breed blueberry plants with desirable traits such as larger berries, higher yields, and disease resistance. Over time, this selective breeding has resulted in plants with genetic differences from their wild counterparts.

Question 9

Which example is an evolutionary adaptation?
A) immunity to a virus caused by vaccination
B) clipped ears on a dog to prevent the dog from developing ear infections
C) webbed feet on a bird
D) a grizzly bear learning to open a Dumpster

Accepted Answer

Webbed feet on a bird are an evolutionary adaptation that help it swim in water and catch prey, thus increasing its chances of survival and reproduction. The other choices are not evolutionary adaptations as they do not involve changes in the genes of a population over time. Vaccination and ear clipping are individual interventions, while Dumpster opening is a learned behavior.

Question 10

Which step in the theory of natural selection do humans impact the most to bring about artificial selection?
A) Individuals in a population vary.
B) Some variation can be passed on to offspring.
C) Populations produce more offspring than the environment can support.
D) There is differential survival and reproduction among individuals in a population.

Accepted Answer

Humans have the most impact on the step of differential survival and reproduction among individuals in a population, as they selectively breed certain individuals with desirable traits to produce offspring with those same traits. This is the basis of artificial selection, and it is through this process that humans have influenced the evolution of many plant and animal species.

Question 11

True or false: Any allele that's present in a population exists because it increases fitness.

Accepted Answer

False. There are several factors that can contribute to the preservation of an allele in a population, including genetic drift, founder effects, and neutral mutations that do not affect fitness. Additionally, some deleterious alleles may persist in a population due to factors such as incomplete dominance or heterozygote advantage.

Question 12

What is the raw material for evolution?

Accepted Answer

The answer of What is the raw material for evolution?...

Question 13

After four observations, Darwin made the inference that natural selection causes what process?

Accepted Answer

The answer of After four observations, Darwin made the inference...

Question 14

What is the primary source for new, unique genes in a population?
A) mutation
B) natural selection
C) artificial selection
D) crossing over

Accepted Answer

Mutation is the primary source for new, unique genes in a population. Mutations are changes in the DNA sequence that can occur spontaneously or be induced by environmental factors, such as radiation or chemicals. These mutations can create new alleles that may or may not be beneficial to an organism's survival and reproduction. Over time, beneficial mutations can increase in frequency within a population through natural selection. Artificial selection and crossing over can also increase genetic variation, but they are not the primary sources for new genes.

Question 15

Which plant is the most fit?
A) a plant with deep roots
B) a plant with large leaves
C) a plant with large flowers
D) Environmental information is required to determine fitness.

Accepted Answer

Fitness in biological terms refers to an organism's ability to survive and reproduce in its environment. Without specific environmental information, it's impossible to determine which plant characteristic (deep roots, large leaves, or large flowers) confers the most fitness. Fitness is context-dependent, varying with environmental conditions such as water availability, sunlight, soil nutrients, and other factors.

Question 16

In what way is artificial selection different from natural selection?
A) There's no difference; both have caused evolution throughout the history of life on Earth.
B) Artificial selection applies to changes in domestic animals only, while natural selection applies to all other species.
C) In artificial selection, human preference is the selecting force; in natural selection, environmental conditions are the selecting force.
D) Artificial selection causes one species to change to another, while natural selection only modifies existing species.

Accepted Answer

Artificial selection involves humans choosing which organisms to breed based on desirable traits, while natural selection involves the environment selecting the traits that provide the best chance of survival and reproduction. Therefore, the selecting force is different between the two types of selection. Option A is incorrect as they are different in the selecting force applied. Option B is incorrect as natural selection applies to all living species, not just non-domesticated ones. Option D is incorrect as natural selection can lead to the formation of new species through mechanisms such as speciation, while artificial selection tends to modify existing species.

Question 17

Artificial selection occurs when an organism's fitness is controlled by ________.

Accepted Answer

The answer of Artificial selection occurs when an organism's fitness...

Question 18

Which factor would exert selection pressure on a population of insects?
A) a new species of bird in the area
B) a fire
C) an earthquake
D) the introduction of a population of feral cats into the area

Accepted Answer

The answer of Which factor would exert selection pressure on...

Question 19

True or false: Any trait that is controlled by genes can be acted on by natural selection.

Accepted Answer

Natural selection acts on any trait that is controlled by genes, as it favors traits that increase an organism's ability to survive and reproduce. However, it is important to note that not all traits are solely controlled by genes and can also be affected by environmental factors.

Question 20

A biologist has been studying two populations of trout in Montana for the last 25 years, when the two populations were established from one common population. In the southern population, the fish now have a slightly different mouth shape. But the northern population hasn't changed from the original type. The new shape works well in catching the type of prey common in the habitat of the southern population. Which is the best explanation for the gene differences in the two populations?
A) The mutation only appeared in the southern population after it was exposed to the new prey.
B) The gene that produces the variation is probably still present in a small percentage of the northern population, but since there's no advantage to having it, individuals with the variation aren't selected.
C) The gene that produces the variation used to be present in a few individuals, but since it wasn't advantageous, individuals with that variation died out.
D) The gene that produces the variation used to be common in both populations, but since it wasn't advantageous in the northern population, the variation died out.

Accepted Answer

The gene that produces the variation is probably still present in a small percentage of the northern population, but since there's no advantage to having it, individuals with the variation aren't selected.

Quiz 11: An Evolving Enemy: Natural Selection

In a population, which individuals are most likely to survive and reproduce?

Which description applies to individuals who are well adapted for a particular environment?

You notice in the fall that the oak trees on campus change color at slightly different times, even though the environment is the same for all the trees. What is the most likely explanation?

A population of caterpillars feeds on the leaves of trees in a forest and is in turn food for birds that eat them off the tree leaves. Given this information, which adaptation would be most likely to evolve?

True or false: The goal of natural selection is to make extreme traits more common.

As natural selection acts on a trait in a population, how will the amount of variation associated with that trait in the population change?

What is an allele?

The blueberries found in a typical grocery store have several gene differences compared to wild blueberries. What has caused this difference?

Which example is an evolutionary adaptation?

Which step in the theory of natural selection do humans impact the most to bring about artificial selection?

True or false: Any allele that's present in a population exists because it increases fitness.

What is the raw material for evolution?

After four observations, Darwin made the inference that natural selection causes what process?

What is the primary source for new, unique genes in a population?

Which plant is the most fit?

In what way is artificial selection different from natural selection?

Artificial selection occurs when an organism's fitness is controlled by ________.

Which factor would exert selection pressure on a population of insects?

True or false: Any trait that is controlled by genes can be acted on by natural selection.